Inorganic Chemistry Frontiers Outstanding Paper Awards 2014–2023

In celebration of the 10^th anniversary of Inorganic Chemistry Frontiers, we are pleased to honour some of the exceptional work published in the journal, as well as the authors behind those articles, with the Outstanding Paper Awards 2014–2023.

Over the past decade, Inorganic Chemistry Frontiers has grown together with our authors, serving as a platform to showcase groundbreaking and cutting-edge research in the field. Following careful consideration of various factors such as article downloads, Altmetric scores, citations, and reviewer feedback, the journal's Editorial and Advisory Board members further selected ten outstanding articles based on their science excellence and potential future impact.

Choosing the winners was a challenge, given the many high-calibre research articles published in the journal. We are deeply grateful to all our authors for their trust and support. It has been a privilege to publish your important work and contribute to the growth of your academic career.

Finally, please join us in congratulating the winners of our Outstanding Paper Awards. We hope that you find their work as inspiring and enlightening as we have. All articles will be free to access for a limited period of time.

Song Gao

Editor-in-Chief, Inorganic Chemistry Frontiers

 

Visible-light radical reaction designed by Ru- and Ir-based photoredox catalysis

Takashi Koike* and Munetaka Akita*

Inorg. Chem. Front., 2014, 1, 562–576

https://doi.org/10.1039/C4QI00053F

This review article discusses important early work on radical reaction systems by action of photoredox catalysis. Essential data of photocatalysts and basic reaction design are highlighted.

Takashi Koike received his doctoral degree under the supervision of Prof. Takao Ikariya from the Tokyo Institute of Technology in 2005. After his graduate career, he worked at the California Institute of Technology alongside Prof. Robert H. Grubbs as a postdoctoral research scholar. In 2007 he returned to the Tokyo Institute of Technology as an assistant professor. In 2021 he was appointed as an associate professor (principal investigator) in the Nippon Institute of Technology. Recently, his efforts have been directed to the development of new organic photoredox catalysts and synthetic methods.

Munetaka Akita was born in Fukuoka, Japan, in 1957. He studied organometallic chemistry under the supervision of Professors Makoto Kumada and Kohei Tamao (Kyoto University), and Professors Akira Nakamura and Hajime Yasuda (Osaka University). After earning his PhD in 1984, he joined the Tokyo Institute of Technology (TokyoTech), where he was appointed as professor in 2002. His research focused on carbon-rich organometallic molecular devices and visible-light-promoted organic synthesis (photoredox catalysis). He retired in 2022 to become an emeritus professor but resumed work at TokyoTech in 2024. TokyoTech later merged with a medical school to become the Institute of Science Tokyo.

 

Cobalt nitrides as a class of metallic electrocatalysts for the oxygen evolution reaction

Pengzuo Chen, Kun Xu, Yun Tong, Xiuling Li, Shi Tao, Zhiwei Fang, Wangsheng Chu, Xiaojun Wu and Changzheng Wu*

Inorg. Chem. Front., 2016, 3, 236–242

https://doi.org/10.1039/C5QI00197H

The development of highly-efficient, stable and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is critical for a range of renewable-energy technologies, including metal–air batteries, fuel cells and water-splitting reactions. However, most of the well-developed electrocatalysts are semiconductors or insulators with poor conductivity, which has profoundly inhibited their overall OER efficiency. The authors report an investigation into metallic cobalt nitrides (Co₂N, Co₃N and Co₄N) arising from electron delocalization modulation for OER electrocatalysts in alkaline solution, for the first time. Benefiting from synergistical engineering of the electrical conductivity and nitrogen content, the simple metallic Co₄N catalyst without modification, exhibits a stable current density of 10 mA cm⁻² at a small overpotential of 330 mV for OER with a Tafel slope as low as 58 mV dec⁻¹ in alkaline medium, which is superior to most unmodified metal oxide electrocatalysts reported to date. Their finding introduces new possibilities for the design of highly active electrocatalysts using synergistical electrical conductivity regulation and composition modulation.

Pengzuo Chen is a professor at the School of Chemistry and Chemical Engineering in Zhejiang Sci-Tech University (ZSTU), China. He received his PhD in inorganic chemistry from the University of Science and Technology of China (USTC) in 2018 under the supervision of Prof. Changzheng Wu. His research interests include the controllable synthesis of low-dimensional inorganic solid materials for electrocatalysis.

Changzheng Wu obtained high BS degree (2002) and his PhD (2007) in the Department of Chemistry at the University of Science and Technology of China (USTC). He has then worked as a postdoctoral fellow in the Hefei National Laboratory for Physical Sciences at Microscale. He is now a full professor at the Department of Chemistry, USTC. Prof. Wu's current research interests focus on the surface-interface synthesis chemistry of inorganic functional materials. He has published more than 200 high-level papers in Nat. Chem., Nat. Phys., Nat. Catal., and has been cited more than 22 000 times (H-factor 82). He has received a number of prestigious awards, including the leader of the innovation research group of the National Natural Science Foundation of China (2023), the leader of the youth team of basic research stability support of the Chinese Academy of Sciences (2022), the National Science Foundation for Distinguished Young Scholars (2019), and is a Fellow of the Royal Society of Chemistry.

 

G-quadruplex DNA targeted metal complexes acting as potential anticancer drugs

Qian Cao, Yi Li, Eva Freisinger, Peter Z. Qin,* Roland K. O. Sigel* and Zong-Wan Mao*

Inorg. Chem. Front., 2017, 4, 10–32

https://doi.org/10.1039/C6QI00300A

G-quadruplex (G4) DNA is formed by self-assembly of guanine-rich nucleic acid sequences, which exist extensively in the chromosomal telomere and the oncogenetic promoter regions. The distinctive structures of G4 DNA offer a great opportunity for specific molecular recognition, and the rational design of small molecular ligands to selectively interact, stabilize or cleave G4 structures, has been considered as a promising strategy for developing potent anti-cancer drugs. Compared with organic molecules, metal complexes possess characteristic structural features, various charges, and additional electromagnetic properties providing advantages for the construction of G4-ligands. This review highlights the recent development of G4-interacting metal complexes, termed G4-ligands, discussing their binding modes with G-quadruplex DNA and their potential to serve as anticancer drugs in the medical field.

Qian Cao obtained her Bachelor's degree in bioscience from Sun Yat-sen University in China in 2004, and received her MSc in applied molecular microbiology and PhD in chemistry from the University of Nottingham in the United Kingdom under the supervison of Prof. Cath Rees and Prof. Michael W. George in 2005 and 2010, respectively. Then she joined Prof. Markku Rasänen's lab as a postdoctoral fellow at the University of Helsinki in Finland. After two and half years of training, she began as an assistant professor at Sun Yat-sen University in 2013 and was promoted to an associate professor in 2021. Her research interests include the chemical biology of transition metal ions and metallodrugs in cancer therapy, and metal mediated immune regulation and targeted intervention.

Peter Z. Qin received his BS in physics from Peking University (Beijing, China) and PhD in biophysics from Columbia University (New York). After postdoctoral training at the University of California, Los Angeles, he started his independent career in 2002 at the Department of Chemistry, University of Southern California (USC), rising through the ranks to full professor. His research focuses on understanding mechanisms of specific nucleic acid recognition by protein complexes and small-molecule compounds that informs genome engineering as well as diagnostic and therapeutic developments. He was a recipient of the NSF Career Award and has been funded by federal agencies including NSF and NIH. He served as the Chemistry Vice Chair of Undergraduate Education from 2017–2021 and the Chairman of Chemistry from 2021–2024.

Roland K. O. Sigel studied chemistry at the University of Basel with biology and biochemistry as a minor subject, and gained a Diploma Thesis in organic chemistry from 1991 to 1995. Then he worked with Bernhard Lippert (University of Dortmund, Germany) on the effect of Pt(II) coordination on the acid–base and hydrogen-bonding properties of nucleobases, and received his doctoral degree summa cum laude (1999). Thereafter he spent three years at Columbia University, New York, with Prof. Anna Marie Pyle (now Yale University) studying ribozymes. From 2003 to 2008 he was an assistant professor at the University of Zürich, Switzerland, and was an associate professor from 2009 to 2016. He was awarded the EuroBIC Medal in 2008, the Alfred Werner Prize (Swiss Chemical Society) in 2009 as well as an ERC Starting Grant by the European Research Council in 2010. He is currently a full professor (2016) of bioinorganic chemistry as well as the Dean (2017) of the Faculty of Science at the University of Zürich, Switzerland. His scientific interests centre around the manifold aspects of metal ion binding to large nucleic acids. Presently, most of the research in his lab is focused on the structural and catalytic role of metal ions in nucleic acids, especially group II intron ribozymes.

Zong-Wan Mao earned his Bachelor's degree from Sichuan University in 1982, and received his MS and PhD from Nanjing University under the supervision of Prof. Wen-Xia Tang in 1991 and 1994, respectively. Then he joined Prof. Liang-Nian Ji's group as a postdoctoral fellow at Sun Yat-sen University. Two years later, he received the Alexander von Humboldt Fellowship, and studied with Prof. Rudi van Eldik at the University of Erlangen-Nuremberg, Germany. He was appointed as an associate professor at Sun Yat-sen University in 1999, and was promoted to full professor in 2004. He is also a Fellow of the Royal Society of Chemistry. His research interests include metallodrugs, molecular probes and biological imaging, chemical biology of metal ions and metalloenzyme chemistry.

 

Transmission electron microscopy as an important tool for characterization of zeolite structures

W. Wan, J. Su, X. D. Zou and T. Willhammar*

Inorg. Chem. Front., 2018, 5, 2836–2855

https://doi.org/10.1039/C8QI00806J

Transmission electron microscopy (TEM) is an important tool for structure characterization of nanoporous zeolite materials. Structural information can be obtained using several TEM-based techniques, for example electron diffraction, high-resolution transmission electron microscopy, scanning transmission electron microscopy and electron tomography, each with its own advantages and limitations. In this review, the authors describe the basic principles of transmission electron microscopy techniques for structural characterization, including recent methodological advancements.

Wei Wan received his PhD from the Institute of Physics, Chinese Academy of Sciences in 2008 and worked as a researcher at the Department of Materials and Environmental Chemistry, Stockholm University, from 2009 to 2017. His research interests focus on developing high-resolution transmission electron microscopy and electron diffraction methods for atomic structure characterization. Since 2017 he has been working as an industrial R&D specialist utilizing electron microscopy as a primary tool.

Jie Su is the facility manager of the X-ray Diffraction Lab and deputy head of the Analytical Instrumentation Center, Peking University. She received her BSc and PhD in chemistry from Peking University (2005 and 2010). After working as a postdoc and a researcher at Stockholm University (2010–2016), she returned to Peking University as a senior engineer. Her research is focused on structure determination of complicated samples with twinning and disorder problems. She also works on the in situ gas adsorption of porous materials using X-ray diffraction.

Xiaodong Zou is a full professor at the Department of Chemistry, Stockholm University. She received her BSc in physics at Peking University in 1984, MSc in metal physics at Beijing University of Science and Technology in 1986, and PhD in structural chemistry at Stockholm University in 1995. After a one-year postdoc at Lund University in Sweden, she joined the faculty at Stockholm University in 1996 as an assistant professor and became a professor in structural chemistry in 2005. Prof. Zou has more than 35 years of experience developing electron crystallographic methods. She and her coworkers have developed various electron crystallographic methods and software, and demonstrated the power of electron crystallography in the structure determination of small molecules (zeolites, metal–organic frameworks, pharmaceuticals) and proteins. Prof. Zou has received several prestigious national awards including the recent IVA Gold Medal in 2024 given by the Royal Swedish Academy of Engineering Sciences, as a distinguished professor of the Swedish Research Council and a Wallenberg Scholar.

Tom Willhammar is a researcher and docent at the Department of Materials and Environmental Chemistry at Stockholm University. He received his PhD from Stockholm University in 2013 in the field of structural chemistry, with a thesis focusing on electron crystallography. After a Postdoc with Prof. Sara Bals at EMAT, Belgium, he is now working at Stockholm University as a researcher. His research centres around electron microscopy, electron diffraction and its application to the structural characterization of nanoporous materials and biopolymers.

 

High performance single-molecule magnets, Orbach or Raman relaxation suppression?

Alejandro Castro-Alvarez, Yolimar Gil, Leonel Llanos and Daniel Aravena*

Inorg. Chem. Front., 2020, 7, 2478–2486

https://doi.org/10.1039/D0QI00487A

This article analyses which magnetic relaxation mechanism limits the blocking temperature (T_B) of high performance single-molecule magnets (SMM). T_B is one of the key figures of merit to assess the properties of a molecular nanomagnet, as it provides the maximum operative temperature of the system. There are different chemical strategies to enhance SMM properties, but their effectiveness depends on the dominant demagnetization mechanism in each case. For instance, the hampering of Orbach relaxation requires the increase of crystal field splitting while Raman demagnetization is connected to molecular vibrations, so ligand rigidification is a typical strategy to diminish the latter mechanism. This article proposes a simple way to determine the relaxation mechanism limiting the blocking temperature, so the most effective strategy to enhance T_B can be chosen for a given molecule. From a set of 17 literature examples of high-performance SMMs, the authors identified which systems are limited by the Orbach, Raman and quantum tunneling mechanisms. Interestingly, all the top performing systems (T_B ≥ 60) are limited by the Orbach mechanism, so crystal field enhancement is necessary to increase record blocking temperatures as vibrational tuning alone is not likely to provide large T_B improvements for the best SMMs.

Alejandro Castro-Alvarez was born in Antofagasta (Chile) in 1984. He studied pharmacy at the Universidad Católica del Norte (2004–2009) and obtained his Master's degree in organic chemistry (Universitat de Barcelona, UB, 2013). He did his PhD thesis under the supervision of Prof. Vilarrasa and Adjunct Prof. Costa, on computational studies of organocatalytic reactions and interactions of macrolides with cytoskeleton proteins. He is currently a professor of pharmacology and medicinal chemistry at the Universidad de La Frontera, and his lines of research are related to obtaining bioactive molecules using bioinformatics tools and artificial intelligence, as well as obtaining these compounds by organic synthesis.

Yolimar Gil was born in Venezuela in 1986. She received her BSc degree in chemistry in 2009 at La Universidad del Zulia. In 2017 she obtained her MSc degree in chemistry at the Venezuelan Institute for Scientific Research (IVIC). She then moved to Chile to do her doctoral studies. In 2021 she received her PhD in chemistry at the University of Chile under the direction of Dr Evgenia Spodine and Dr Daniel Aravena. In 2022 she obtained a postdoctoral position at the University of Chile. Her research interests include the synthesis and characterization of novel lanthanide complexes and the study of their magnetic and/or optical properties.

Leonel Llanos was born in Santiago, Chile in 1993. He studied chemistry at the University of Santiago, Chile and received his BSc degree in 2017. In 2023, he obtained his PhD in chemistry at the same university under the direction of Dr Daniel Aravena and Dr Luis Lemus. In 2024, he obtained a postdoctoral position at the University of Chile. His research is focused on the design, synthesis and study of organic and transition metal-based materials showing interesting photophysical properties by means of time-resolved spectroscopic techniques and theoretical calculations.

Daniel Aravena is an associate professor at the University of Santiago, Chile. He received his undergraduate degree in chemistry from the University of Chile in 2009 and his PhD from the University of Barcelona (2013). After a postdoctoral stage at the Max-Planck Institute for Chemical Energy Conversion, he joined the University of Santiago, Chile in 2015. His research focuses on the calculation of spectroscopic and magnetic properties of diverse inorganic systems, such as lanthanide single molecule magnets and TM-based luminescent complexes.

 

Large easy-axis magnetic anisotropy in a series of trigonal prismatic mononuclear cobalt(II) complexes with zero-field hidden single-molecule magnet behaviour: the important role of the distortion of the coordination sphere and intermolecular interactions in the slow relaxation

Aritz Landart-Gereka, María Mar Quesada-Moreno, Ismael F. Díaz-Ortega, Hiroyuki Nojiri, Mykhaylo Ozerov, J. Krzystek,* María A. Palacios* and Enrique Colacio*

Inorg. Chem. Front., 2022, 9, 2810–2831

https://doi.org/10.1039/D2QI00275B

This article reports the use of a N₆-tripodal Schiff base ligand, (S)P[N(Me)N=C(H)Py]₃, to specifically design a family of Co^IIN₆ trigonal prismatic cationic complexes [Co(L)]²⁺ bearing different counter-anions (CoCl₄²⁻(1), ZnCl₄²⁻(2), ClO₄⁻(3) and BF₄⁻(4)). The change of the counter-anion induces slight but non-negligible variations of the distortion of the CoN₆ coordination sphere from trigonal prismatic (TPR-6) to octahedral geometry (OC-6) following the Bailar pathway, so that this distortion decreases on passing from 1 to 4. All these complexes exhibit large easy-axis magnetic anisotropy as revealed using a combination of dc magnetic, FIRMS (far infrared magnetic spectroscopy), HFEPR (high-field electron paramagnetic resonance) measurements and theoretical calculations. The easy-axis magnetic anisotropy was shown to increase as the distortion from trigonal prismatic geometry decreases on going from 1 to 4. This is the first time that such magneto-structural correlation was established from experimental results. Besides this, the change of the counter-anion was also shown to affect the Co⋯Co intermolecular distances and crystal packing (shorter Co⋯Co distances and large angles between the magnetic axes favour QTM), which together with the easy-axis magnetic anisotropy determine the ac dynamic properties of 1–4. Thus, 1 does not show slow magnetic relaxation even in the presence of a dc magnetic field due to the relatively strong dipolar interactions involving both units, with a short Co⋯Co distance (<6 Å) between the cationic [Co(L)]²⁺ and the anionic [CoCl₄]²⁻ units. Compounds 2–4 do not show clear maxima above 2 K, but they exhibit slow relaxation and MSMMs (mononuclear single-molecule magnets) behaviour under the corresponding optimal field (field-induced MSMM), or in the case of the latter two, after magnetic dilution (zero-field hidden MSMM). On passing from 2 to 4, the relaxation time above 4 K through the Raman process increases, which agrees with the parallel increase of the uniaxial anisotropy in these compounds. Finally, the hysteresis for the trigonal prismatic complexes in the presence of magnetic field decreases in the order 3 > 2 > 4 > 1, which is due to combined effects of the axial anisotropy and QTM relaxation. The results obtained in this work can be considered as useful guidelines for designing Co^II based MSMMs complexes with improved properties.

Aritz Landart-Gereka was born in San Sebastian, Spain in 1996. He obtained his degree in chemistry at the University of the Basque Country (UPV, Spain) in 2018, and received his PhD in 2024 under the supervision of Prof. Enrique Colacio Rodríguez and Dr María Ángeles Palacios López. During his PhD, he worked on the design, synthesis and characterization of diverse Co(II) SIMs based on tripodal ligands, as well as various silica-nanoparticle based materials containing such compounds. He now works as a physics and chemistry teacher in the Basque Country.

María Mar Quesada-Moreno obtained her PhD at the University of Jaén (UJA, Spain) under the supervision of Prof. Juan Jesús López-González and Dr Juan Ramón Avilés-Moreno. There she explored chiral recognition processes and spontaneous resolution of chirality in the solid phase using the chirality sensitive vibrational circular dichroism technique. During her two-year postdoctoral stay at Prof. Melanie Schnell's group in Hamburg (Germany), she used broadband rotational spectroscopy in the gas phase to analyze the chiral composition of essential oils and the structures of large complexes where dispersion interactions play a key role. After that, she joined Prof. Enrique Colacio's group at the University of Granada (Spain) for three years, and later Prof. Amparo Navarro's group at UJA, where she works as a Ramón y Cajal postdoctoral research fellow. During these last two periods her research encompasses the preparation of multifunctional molecular materials with interesting magnetic properties or association of magnetic, chiral and/or luminescence properties, which can have important technological applications. During her last period at UJA, she also worked on predicting the luminescence properties of coordination compounds or conjugated pi-systems with biological relevance.

Ismael F. Díaz-Ortega is an assistant professor in the Department of Chemistry and Physics of the University of Almería, and is currently involved in the research ‘Synthesis and characterization of new water-soluble coordination compounds: study of their catalytic and photochemical properties in water’ and ‘New biologically active coordination compounds’ focusing on the use of lanthanides. He graduated in chemistry at the University of Granada and obtained his PhD in inorganic chemistry (molecular magnetic materials) at the University of Granada. After completing his PhD, with the dissertation “Influence of Ligands on Single Molecule Magnet Based on Lanthanide Ions: Magneto-Structural and Theoretical Study”, he obtained a postdoctoral scholarship funded by the Institute of Material Research (IMR) at Tohoku University (Sendai, Japan). He has co-authored 23 research publications and his publications have received over 327 citations with an h-index = 11 (Web of Science).

Hiroyuki Nojiri is a professor at the Institute for Materials, Tohoku University (2004-Present). He was a research associate at the Institute for Solid State Physics, University of Tokyo (1991–1995), PhD at Osaka University (1993), associate professor at the Institute for Material Research, Tohoku University (1995–2001), and professor in the Department of Physics, Okayama University (2001–2004). His research focuses on the study of quantum magnetism in a wide range, strongly correlated electron system and molecular magnets, high magnetic field and high frequency THz-electron spin resonance in magnetic compounds, X-ray and neutron scattering in high magnetic field, study of field induced phase transitions.

Mykhaylo Ozerov is a research faculty member at the National High Magnetic Field Laboratory at Florida State University. He earned his BSc (2003) and MSc (2005) degrees with honors in optics and physics from Taras Shevchenko National University of Kyiv, Ukraine. He conducted his PhD research, entitled ‘High-Field Electron Spin Resonance in Low-Dimensional Spin Systems’, at the Dresden High Magnetic Field Laboratory (HLD) under the supervision of Sergey Zvyagin and obtained his PhD, cum Laude, (2011) from Dresden Technical University, Germany. He enhanced the functionality of THz instrumentation for spectroscopic studies in high magnetic fields during his postdoctoral tenure at the HLD, Dresden, Germany (2015), and at the FELIX Laboratory, Nijmegen, The Netherlands (2016). In 2017, he joined the National High Magnetic Field Laboratory in Tallahassee, where he oversees the infrared spectroscopy program at the user DC-field facility. He has advanced the use of far-infrared spectroscopy in high magnetic fields to investigate spin–phonon interactions and to elucidate the zero-field splitting energy in single-molecule magnets. Currently, his research focuses on the low-energy excitation spectrum in two-dimensional layered materials and Kitaev magnets.

Jurek Krzystek is a research scientist at the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida, he graduated from Warsaw University with a BSc and MSc in chemistry in 1973 and 1974, respectively. He pursued his graduate studies in chemical physics at the Institute of Physics, Polish Academy of Sciences, where he received a PhD in 1983 under the supervision of the late Prof. Jerzy Prochorow. There followed two postdoctoral appointments: the first at the Physics Institute of the University of Stuttgart in Germany (adviser: the late Prof. Hans-Christian Wolf) and then at the Chemistry Department, University of Washington in the USA (adviser: Prof. Alvin L. Kwiram). Dr Krzystek has been working at the NHMFL since 1995. He specializes in the spectroscopy of molecular systems, and in particular, electron paramagnetic resonance (EPR). Using the high magnetic fields generated by the NHMFL magnets, he has pursued high-frequency and -field EPR (HFEPR) techniques as a characterization method for various electron spin systems, including but not limited to, transition metal coordination complexes.

María Ángeles Palacios was born in Granada, Spain. She received her Bachelor's degree in 2004 from the University of Granada and her doctorate from the same institution in 2010 under the supervision of Prof. Colacio. In 2011, she was awarded with a MEC postdoctoral fellowship to join Prof. Brechin's research group at the University of Edinburgh, and moved to the Institute Charles Gerhardt Montpellier (CNRS) in France to work with Prof. Larionova and Dr Guari in April 2014. In June 2016, she came back to the University of Granada with a Juan de la Cierva Incorporación Fellowship. In 2018 she was promoted to assistant professor and to associate professor in 2022. Her research activity focuses on the synthesis of new multifunctional molecular materials based on mononuclear lanthanide coordination compounds, which combine single-ion magnetic behaviour with/or chiro-optical properties as well as their encapsulation in/attachment to nanoparticles and metal–organic cages/frameworks.

Enrique Colacio received his BSc and PhD in chemistry from the University of Granada in 1979 and 1983, respectively. He joined the Department of Inorganic Chemistry of the University of Granada and was promoted to associated professor and then to full professor in 1986 and 2000, respectively. He was a postdoctoral fellow at the Laboratoire de Chimie de Coordination, Toulouse, France (Paule Castan's group) and he has been a visiting scientist at the University Claude-Bernard, Lyon I France (Dominique Luneau's group 2005), University of Bretagne Occidental, Brest, France (Smail Triki's group 2006, 2017), School of Chemistry, University of Edinburgh, UK (Brechin's group 2010 and 2012) and University of Jyváskyla, Finland (Reijo Sillänpäa's group 2013). He has led more than 25 research projects, and 13 PhD theses. His research interest focuses on the design, preparation and study of functional and multifunctional molecular materials based on coordination compounds (molecular magnets, SMMs, SIMs, spin crossover complexes, molecular magnetic refrigerants, luminescent materials, chiral magnets, luminescent chiral magnets with circularly polarized luminescence, and so forth). In addition, he is also interested in processing these materials on different supports (SiO₂ and Au nanoparticles, polymeric thin-films, mesoporous silica matrix, surfaces and so on).

 

Photocatalytic CO₂ reduction on Cu single atoms incorporated in ordered macroporous TiO₂ toward tunable products

Cong Chen, Ting Wang, Ke Yan, Shoujie Liu, Yu Zhao and Benxia Li*

Inorg. Chem. Front., 2022, 9, 4753–4767

https://doi.org/10.1039/D2QI01155G

This article reports a Cu single-atom-incorporated three dimensional-ordered macroporous TiO₂ (Cu/3DOM-TiO₂) catalyst designed for photocatalytic CO₂ reduction using H₂O as a proton donor in both gas–solid and liquid–solid systems. The introduction of Cu single atoms not only broadens the light absorption range but also provides specific active sites for CO₂ reduction. The Cu/3DOM-TiO₂ photocatalyst demonstrates superior activity and selectivity for CH₄ production in the gas–solid system, while favorably generating C₂H₄ in the liquid–solid system. This research offers novel perspectives on achieving efficient photocatalytic CO₂ reduction to desired products through the rational design of photocatalysts and optimization of reaction conditions.

Cong Chen received his Bachelor's degree from the School of Chemical and Pharmaceutical Engineering at Qilu University of Technology (2020) and Master's degree from the School of Chemistry and Chemical Engineering at Zhejiang Sci-Tech University (2023). For his postgraduate study, he was honored with the National Scholarship for Graduate Students, the Outstanding Graduate of Zhejiang Province, and the Excellent Master's Thesis of Zhejiang Province.

Benxia Li is now a full professor in the School of Chemistry and Chemical Engineering at Zhejiang Sci-Tech University. She received her BS degree from Anhui University (2003) and PhD from the University of Science and Technology of China (USTC, 2008, supervised by Prof. Yi Xie). From 2008 to 2016, she worked at Anhui University of Science and Technology and conducted research visits at the Department of Physics of the Chinese University of Hong Kong (2012–2013). Her research focuses on the controllable synthesis of inorganic nanomaterials and their applications in the fields of photocatalysis and photo-thermal catalysis.

 

A ratiometric fluorescent probe based on a dual-ligand lanthanide metal–organic framework (MOF) for sensitive detection of aluminium and fluoride ions in river and tap water

Runnan Wang, Hao Zhang, Sibo Wang, Fanxu Meng, Jing Sun,* Dawei Lou and Zhongmin Su*

Inorg. Chem. Front., 2023, 10, 1534–1542

https://doi.org/10.1039/D2QI02554J

In this article, a new double-emission lanthanide metal–organic framework (Eu-BDC-NH₂/TDA) with a triclinic crystal system and a P1̄(2) space group has been synthesized. This material can be used as a ratio fluorescent probe to detect Al³⁺ and F⁻ in river water and tap water. It is noteworthy to mention that this is the initial instance of a dual-ligand dual-emission ratio Eu-MOF fluorescence sensor capable of simultaneously detecting both Al³⁺ and F⁻, exhibiting significant potential for further development. The Eu-BDC-NH₂/TDA can quickly and easily find Al³⁺ and F⁻ using the ratio change between I₄₃₀/I₆₂₁ at two launch centers. Under ultraviolet light, the color of EU-BCD-NH₂/TDA changes from red to blue as the concentration of Al³⁺ or F⁻ increases. The possible detection mechanism was investigated using XRD, FT-IR, N₂ adsorption–resorption and XPS characterization. Considering the aperture size of MOF explains the reason why Eu-BDC-NH₂/TDA has specific sensing for Al³⁺ and F⁻. The ratio fluorescent probe has several advantages, including high sensitivity, high selectivity, low detection limit, strong anti-interference, fast response time, and naked eye visual detection for Al³⁺ and F⁻ in ethanol medium. As a fluorescent probe, Eu-BDC-NH₂/TDA has demonstrated practical utility in both river water and tap water. It offers a novel approach for the detection of Al³⁺ and F⁻ in actual water samples and has the potential to make significant advancements in future engineering applications.

Runnan Wang has been a doctoral candidate in the School of Materials Science and Engineering at Changchun University of Science and Technology since September 2021, under the guidance of Prof. Jing Sun. Her research direction is the preparation and properties of lanthanide metal–organic framework luminous materials.

Jing Sun's research primarily focuses on the design and synthesis of luminescent materials and metal–organic frameworks (MOFs), providing a general methodology for constructing multifunctional luminescent Ln-MOF sensing materials. Her work has demonstrated significant potential applications in fields such as non-contact temperature measurement, photo/electrochemistry, metal ion detection, and antibiotic sensing. Prof. Sun has successfully led or participated in the completion of over 20 research projects, with 3 ongoing projects currently under her supervision. She has published one monograph as the first author, holds two authorized Chinese invention patents, and has published over 50 SCI-indexed papers in high-impact journals, including Inorganic Chemistry Frontiers and the Journal of Colloid and Interface Science. In recognition of her contributions to the field, Prof. Sun serves as a member of the 7th Rare Earth Crystal Professional Committee of the China Rare Earth Society, and she is the director of the Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry.

Zhongmin Su's research focuses on the design, synthesis, and investigation of photoelectric, catalytic, and related properties of novel functional materials, particularly metal–oxygen clusters (polyoxometalates, POMs) and metal–organic frameworks (MOFs). His work integrates experimental studies with advanced computational techniques such as density functional theory and ab initio methods. His contributions include the systematic theoretical exploration of electron transfer, redox behavior, and catalytic properties within representative POM and MOF systems. He has made significant strides in uncovering the mechanisms governing electron transfer and luminescence efficiency in small-molecule and polymer-based organometallic optoelectronic complexes, leading to the design and synthesis of novel optoelectronic materials. With an impressive research output, he has published 285 SCI-indexed papers including in journals such as J. Am. Chem. Soc., Angew. Chem., Int. Ed. and Nat. Commun.

 

Challenges and advancement in direct ammonia solid oxide fuel cells: a review

Dattatray S. Dhawale,* Saheli Biswas, Gurpreet Kaur and Sarbjit Giddey

Inorg. Chem. Front., 2023, 10, 6176–6192

https://doi.org/10.1039/D3QI01557B

Ammonia contains 17.6 wt% hydrogen and is considered a suitable medium for hydrogen storage and as a carrier, facilitating CO₂-free energy systems which can play a critical role in the transition to clean energy. Ammonia is also an ideal carbon-free fuel for power generation in direct ammonia solid oxide fuel cells (DASOFCs). In DASOFCs, ammonia cracks into hydrogen and nitrogen in situ in the anode chamber, and hydrogen is consumed in the electrochemical process; hence, a separate ammonia cracking and hydrogen/nitrogen separation unit is not required. However, key technological challenges must be addressed to realize the potential of ammonia as a fuel in SOFCs. This review discusses the technological challenges such as ammonia safety, open circuit voltage (OCV) stabilization, thermal shocks, NO_x/N₂O emission, nitride formation, nickel coarsening, limited power densities, and sealing issues, and the recent advancements in DASOFCs technology. The review also covers the performance of state-of-the-art anode materials and newly emerging proton-conducting materials for DASOFCs, along with the various approaches used for the high-efficiency and long-term stability of DASOFCs systems at the kilowatt (kW) scale. Overall, this review article has put together the current challenges, and the research advances in the DASOFC area, to pave the way for developing kilowatt-scale systems, highlighting the challenges that still need to be addressed and the future recommendations for DASOFC technology development for the single-step conversion of ammonia to power.

Dattatray S. Dhawale is a senior research scientist in the Energy Business Unit at the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia. His achievements have been honored by several prestigious fellowships, such as Brain Korea-21 (Hanyang University, South Korea), MANA NIMS Japan, Lindau Nobel Laureate Meeting, Germany, etc. His research expertise is in the design and development of functional nanomaterials for renewable energy conversion for hydrogen and ammonia production and utilization by electrolyzer and fuel cell technology. He has published over 80 peer-reviewed journal articles, which have attracted more than 6300 citations with an h-index of 44 and an i10 index of 65, four patents, and several book chapters. He receives regular international recognition for his work, including being listed among the World's Top 2% of Scientists in the field of ‘Energy’ (Stanford University rankings).

Saheli Biswas is a research scientist at the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia, working on green hydrogen production via high-temperature solid oxide electrolysis technology and commercialization of the technology. Her expertise lies in renewable energy, electrochemical technologies for green fuel production and decarbonization, product commercialization, ceramic materials development, heterogeneous catalysis, coating formulation and techniques, fuel cell and electrolyzer testing, data acquisition, and numerical analysis. She has published more than 26 scientific papers and holds two patents. She holds a PhD in chemical engineering from Monash University, Australia (2019–2022), an MS in chemical engineering from Lehigh University, USA (2014–2017), and a BTech in chemical engineering from India.

Gurpreet Kaur is a senior research scientist and leads the Electrochemical Energy Systems team at CSIRO. Dr Kaur's team conducts R&D to develop next-generation electrochemical technologies for the production and utilization of green fuels like hydrogen and ammonia for the decarbonization of the energy sector. Dr Kaur has been working on understanding the fundamental reaction mechanisms and materials development for electrochemical energy systems, including water/carbon-dioxide conversion to transportable chemicals and fuels, electrochemical ammonia synthesis, and ammonia-assisted water electrolysis utilizing renewable energy. Dr Kaur did her PhD on solid oxide fuel cells at the Indian Institute of Technology Delhi. She has authored several technical publications, including high-impact journal articles and patent applications for efficient hydrogen production from electrolysis. Dr Kaur is supervising PhD and post-doctorate students in collaboration with Australian universities. Dr Kaur and the team won the “Growing our impact” award in 2023 for demonstrating increasing real-world impact for CSIRO with strong alignment to the energy strategy.

Sarbjit Giddey is a senior principal research scientist and currently group leader in the Energy Technologies Program at CSIRO. With over 20 years of research and development experience in hydrogen-related technologies, Dr Giddey's contributions have been instrumental in advancing renewable fuels production, utilization, and battery recycling technologies. As the leader of a dynamic group with diverse expertise, he drives ground-breaking R&D initiatives to enhance energy conversion efficiencies and promote the economic viability of emerging zero-emission technologies. His immense knowledge and expertise have been shared with the scientific community in over 80 refereed publications and several book chapters, patents, and provisional applications. The impact of his research is evident, with over 7300 citations to his name, underlining the far-reaching influence of his work.

 

A latest-generation fluoride with excellent structural stiffness for ultra-efficient photoluminescence and specific four-peak emission temperature sensing

Kejie Li, Mengmeng Dai, Zuoling Fu,* Zhiying Wang, Hanyu Xu and Rong Wang

Inorg. Chem. Front., 2024, 11, 172–185

https://doi.org/10.1039/D3QI01902K

Fluorides have garnered significant attention as rare-earth-doped luminescent probes due to their low phonon energy. However, the synthesis of LiYF₄ is hindered by its complex and uncontrollable fabrication methods, which severely limit its further exploration and application. In this study, the authors employed a one-step hydrothermal method to synthesize LiYF₄:Ln³⁺ with micron-sized cones and nano-spherical structures. When doped solely with Er³⁺, self-sensitized luminescence was achieved under multi-wavelength excitation. Crystal structure analysis, electronic band structure properties, morphological analysis, and Debye temperature calculations confirmed the superior photoluminescence performance of LiYF₄:Yb³⁺,Er³⁺ compared to commercial phosphors. Furthermore, by constructing a cross-relaxation process between Ce³⁺ and Er³⁺ ions (⁴I_11/2 + ²F_5/2 → ⁴I_13/2 + ²F_7/2), a significant enhancement of the four-peak emission intensity for Er³⁺ in the NIR-IIb region was observed, which further improved the relative sensitivity of thermal coupling temperature sensing based on four-peak emission. Additionally, phonon-assisted energy transfer between Ho³⁺ (⁵I₆) and Er³⁺ (⁴I_13/2) enabled non-thermal coupling temperature sensing based on the NIR-II emission of Ho³⁺ and Er³⁺. These results demonstrate the exceptional potential of rare-earth-doped LiYF₄ as a temperature-sensitive probe.

Kejie Li received his BSc degree from Nanyang Normal University in 2020. Afterward, he joined the College of Physics, Jilin University, as a PhD candidate under the direction of Prof. Zuoling Fu, working primarily on the controllable synthesis and temperature sensing of rare-earth doping nanomaterials, and near-infrared biological imaging.

Zuoling Fu received her PhD in 2007 from the Changchun Institute of Applied Chemistry Chinese Academy of Sciences (CIAC) and worked as a postdoctoral fellow at Pukyong National University in South Korea during 2007–2009. She has been a full professor in the College of Physics, Jilin University, since 2013. Her main research fields are rare-earth functional materials, temperature sensing, and near-infrared biological imaging.

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