Themed collection Journal of Materials Chemistry C HOT Papers

The development of new organic ferroelectrics has encountered some challenges and opportunities. In this perspective, we have summarised synthetic and computational design principles for high-performance organic ferroelectrics.

Photon upconversion (UC) stands for the conversion of low to high energy photons, a promising approach to improve solar cells. While high efficiencies can be obtained in liquid UC, will a solid UC device be able to reach such levels?

For development of multifunctional smart devices, this perspective focuses on vertical transistors with short channels aided by nanotechnology.

A generalized picture on how surface charge imbalance mediated by doping can affect the gas sensing behavior of metal oxide chemiresistive systems.

The structure of the electrical-double layer of the graphene/aqueous–electrolyte interface is challenging to model and characterize experimentally. Here we review the published data and discuss their interpretation in the context of the EDL theory.

This review summarizes the solution-processing techniques toward organic semiconductor devices from the perspective of the physical state of the film-forming substrates.

This article reviews the historical and recent advances in the design, synthesis, and implementation of the 6-5-6-5-6 π-fused-ring indenofluorene-based semiconductors in organic transistor and solar cell devices.

Perspectives on carbon-centred neutral π-radicals are discussed in terms of materials design, optical and electrochemical properties, target applications and intriguing research directions that deserve further attention.

Solvent engineering is playing an important role in improving the performance of perovskite light-emitting diode (PeLED) devices. In this review, solvent-based strategies for efficient PeLEDs are mainly discussed and an outlook is also proposed.

Featuring a combination of size-tunable emission wavelengths, high thermal stability, and low cytotoxicity, carbon quantum dots (CQDs) have opened up a new possibility for next-generation displays.

Combining chemical reaction and low-temperature annealing allows to form perfectly stoichiometric 1T-VS₂, where multiple charge density wave orders are observed due to strong electron–phonon coupling.

Acetic acid probes based on Zinc complexes with high stability and selectivity were successfully prepared by reacting the H₂tBuCarPy ligand with ZnBr₂, which exhibit reversible vapor-chromism during the uptake and release of acetic acid.

An OLED based on TTM-3PDMAC achieved a maximum external quantum efficiency (EQE) of 3.1% with an emission peak at 830 nm.

LaBS₃ possesses a large SHG effect, high laser-induced damage threshold, wide band gap, and high thermal stability.

By the molecular design of a bipolar single-component Sm³⁺-containing metallopolymer, its light/electricity stimuli white-light and visual sensing on Cu²⁺ ion, render Ln³⁺-containing metallopolymers a new platform to multi-stimuli-response materials.

A facile dry-transfer method is developed to construct reconfigurable self-powered photodetectors. Benefitting from the reconfigurability of these individual building blocks, they can be assembled into multifunctional pluggable photodetectors.

A salt-inclusion strategy was adopted to construct two novel fluorooxoborates CsAB₈O₁₂F₂·CsI (A = K⁺, NH₄⁺). Therein, CsKB₈O₁₂F₂·CsI shows moderate SHG response (0.6 × KDP at 1064 nm) and short phase-matching (PM) SHG wavelength (270 nm).

Increasing the twist angles between donor and acceptor units in 9H-selenoxanthen-9-one-based emitters can modulate the lowest triplet excited states (³LE or ³CT), achieving pure RTP and dual emission of RTP and TADF, respectively.

A new hybrid fluorooxoborate was discovered following the strategy of combining two birefringence-active units. The large birefringence and short absorption edge make it a potential short-wavelength ultraviolet birefringent crystal.

Topological heterogeneous microgels have been obtained via self-assembly of stimuli-responsive, semi-confined space processing block copolymers. The synergistic capabilities have been integrated into a microscale entity for the first time.

High luminescence dissymmetry factors of +7.26 × 10⁻² and −5.45 × 10⁻² of chiral thermally activated delayed fluorescence emitters were obtained by co-assembly with achiral liquid crystal molecules.

Solid mixture of PbS quantum dot and a directly attached emitter penetrating the ligand layer enables photon upconversion from near infrared.

Through the combination of perylene diimide and triphenylamine moieties, a perovskite solar cell with DPT as the electronic transport material exhibited a PCE of 20.07%.

The single crystal field-effect transistor of 5,15-bis(triisopropylsilyl)ethynyltetrabenzoporphyrin exhibited better hole mobility than its metal complexes, with efficient charge transport through π–π stacking along tetrabenzoporphyrin units.

Three acceptor–donor–acceptor type fused-ring non-fullerene acceptors of FOR-IN, FOR-1F and FOR-2F, were synthesized with the same pyran-composed backbone but different terminals, affording over 15% efficiency in organic solar cells.

Cs₂ZnBr₄:Mn²⁺ and its composite film demonstrate good X-ray scintillation performances with a spatial resolution of 5.06 lp mm⁻¹ in X-ray imaging.

A perovskite photodetector with bio-inspired micro area concentrated structures has been fabricated for weak light imaging. The photodetector exhibits high detectivity (1.37 × 10¹³ Jones), and it can achieve weak light imaging under 0.64 μW cm⁻².

The isomerism effect on the aggregate emission properties of perylene diimide derivatives is studied. Banking on their bright emission, a cellular imaging test based on their nanoparticles is also conducted.

A ratiometric fluorescent sensor, Flu@Eu-dbia, was self-assembled through host–guest interaction for the detection of tyramine. Distinguishable color change and the logic gate endowed Flu@Eu-dbia with great potential in food safety monitoring.

Dielectric properties of Nb-doped TiO₂ single crystals measured before and after the special post-annealing with Ga₂O₃ embedding powder, shedding light on local structure engineering for permittivity boosting in dielectric materials.

The Rb₃Ba₃Li₂Al₄B₆O₂₀F crystal is a competitive ultraviolet NLO crystal, which not only can output 266 nm laser but also exhibits excellent comprehensive performances, such as large NLO coefficient, small walk-off and large acceptance angles.

MXenes are 2D materials with many promising applications, but their Raman spectra is still poorly understood. We developed a computational method to simulate Raman spectra of MXenes accounting for temperature, surface composition, and defects.

A microfluidic thermal mass flow sensor with ultra-high thermal sensitivity, based on planar micro-machining technology and a phase-change material is developed.

Hollow cubic CdS@CoS/WS₂ dual S-scheme heterojunction superstructures with a full spectral response showing good photothermal–photocatalytic properties are fabricated using a simple sulfidation and hydrothermal method.

A strategy to obtain low Jd in OPDs from a material point of view is presented: fluorination of the electron donor unit in a donor–acceptor type conjugated polymer is an effective way to reduce the Jd of OPDs by suppressing the trap DOS.

Combining the advantages of GQDs and InSe, GQD/InSe 0D–2D MvdWH-based photodetectors with a responsivity of 27.48 A W⁻¹ and a detectivity of 1.2 × 10¹² Jones are proposed.

Hundred grams of C-dots are produced by directly heating metal citrate/urea/metal ions. The C-dots have absorption ranging from 300 to 500 nm with a QY of 70%, and a Stokes shift of 0.73 eV. These optical properties are suitable for efficient LSCs.

The desired dynamic spectra of plants can be achieved by placing PSC light convertors with different light qualities on blue LED chips.

The crystal structure and the resultant electronic structure of Ta-supplemented bismuth oxides were altered with the amount of Ta added. Their optoelectronic and redox properties were elucidated both experimentally and theoretically.

The simple chalcogen atom substitution of quinoidal molecules and polymers induces the significant alternation of various properties as well as molecular geometries.

Artificially inducing abundant oxygen vacancies in perovskite-structured materials is an effective method to improve sensing activity.

Three DPP-based dual-acceptor conjugated polymers comprising different proquinoidal heterocyclic acceptors are synthesized and their structure–property relationship using a transistor and their conductive states by doping are investigated.

A dual-mode self-calibrating temperature measurement strategy was proposed, by leveraging the temperature-dependent ratios of UC emission intensities from the thermally-coupled and non-thermally coupled energy levels of Er³⁺ ions.

With a facile halide and phase modulating approach, deep-blue emissive quasi-2D perovskite films involving fewer intervening 2D phases are realized, for efficient delivery of excitons to light-emitting phases via streamlined energy transfer.

Sequential processing based devices show improved power conversion efficiency and stability compared to their blend casting counterparts. Systematic characterization reveals the underlying mechanism.

Volatile hydrazine hydrate (HH) and non-volatile glucose (GLC) were used as n-type dopants to prepare thickness-insensitive MoO_x HTLs in high performance OSCs.

A hydrogen bonded pyridine-thieno[3,2-b]thiophene-pyridine type building block TTPY has been synthesized for π-conjugated polymers and their application in organic electronic devices.

We report the enhanced photothermal stability of in situ grown FAPbBr₃ perovskite nanocrystals in polyvinylidene fluoride by incorporation of Cd²⁺ ions, which have potential applications in backlight devices.

In this work,monodispersed PS@TA–Fe(III) nanospheres with intense light absorption and interface adhesion were synthesized for the non-iridescent structural coloration of textiles.

Organic photodiodes composed of all-polymer active layers achieve a stable morphology, associated with superior electrical and thermal stabilities without sacrificing their performance.

A narrow band and stable CsPbBr₃ light converter was elaborately designed for laser-driven projection displays.

A novel phenomenon of negative ΔT is observed during indirect characterization, while positive values for direct characterization.

A S-scheme α-Fe₂O₃/g-C₃N₄ composite was designed and fabricated. The α-Fe₂O₃/g-C₃N₄ showed improved photocatalytic activity for Aza-Henry reaction. S-scheme mode of charge transfer in composite enhanced the catalytic performance.

A smart all-hydrogel-based dressing fabricated by a self-healing cross-linking strategy can achieve effective monitoring of wound temperature, mechanical strain and on-demand drug delivery to inhibit bacterial growth in order to promote wound healing.

A main chain liquid crystalline polymer has been prepared via melting polycondensation of a bifunctionalized furan monomer (DMFD) from inedible biomass with a photo-responsive azobenzene unit, which can be used in information storage.

FeCoNiCu_xMn (x = 0, 0.1, 0.3, 0.5, 0.7 and 0.9) and FeCoNiCu_0.1MnB_0.05 high entropy alloys (HEAs) were prepared via an improved swing ball-milling method.

Mechanoluminescence peaked at 355 nm (Bi³⁺: ³P₁→¹S₀) was observed in an orthorhombic phase compound of LiYGeO₄:Bi³⁺, which has widened the mechanoluminescence spectral wavelength into UV range.

The luminescence mechanism of the vacancy ordered lead-free perovskite synthesized using a hydrothermal method is fully discussed. Finally, this material is applied to white light emitting diodes and X-ray imaging.

Responsive, efficient, and multifunctional anticancer nanoparticles were constructed for near-infrared fluorescence-guided synergistic photothermal therapy and chemotherapy.

CuSCN as HTL is used in inorganic planar carbon electrode-based Sb₂S₃ solar cells resulting in a higher PCE (1.95%) compared to Au (PCE = 1.75%). Also, this planar device architecture enables a semitransparent solar cell (PCE = 1.67%, AVT = 27.6%).

CsPbBr₃@PbBrOH with superior luminescence properties and stability was successfully synthesized by a water induction technique.

The polycrystalline CaBi₂Nb₂O₉ ceramics with the addition of B₂O₃ can realize a large d₃₃ of 20.4 pC N⁻¹ and an ultra-high electrical resistivity of 1.4 × 10⁷ Ω cm (at 600 °C), while still retaining a high T_C of 958 °C.

A simple, efficient and general approach for all-visible-light switching of photochromic diarylethenes is developed through triplet sensitization from CdS nanocrystals, which has high potential for all-visible-light activated optoelectronics.

A first principles-based machine learning potential is developed to model the phonon transport properties in full Heusler CsK₂Sb and CsK₂Bi taking account of all higher-order phonon interactions.

The ratio of Si-29 nuclear magnetic resonance coherence lifetimes for Q⁴ and Q³ sites under magic-angle spinning and a π-pulse train in silicate glasses can detect phase separation, even at small scales where the glass appears optically homogenous.

An up-conversion charging process in a Gd₃Ga₅O₁₂:Tb³⁺ persistent phosphor is achieved upon illumination by a 488 nm laser. An energy-transfer mechanism dominates the up-conversion excitation.

The Bi₂O₂Se/MoO₃ heterojunction has the characteristics of high stability and detection in the optical communication spectrum, which provides a simple and effective method to fabricate large-scale, fast response, broadband flexible array optoelectronic devices.

A balance between the mechanical and electrical performance is achieved in conjugated polymer blend films with an optimal blend ratio.

By preparing a host–guest MOF to elaborately arrange donor–acceptor ligand and dye guests, second-harmonic generation and two-photon-pumped lasing can be switched in a MOF crystal by orthogonally manipulating the excitation polarization direction.

The performance of CsPbCl₃-based photodetector gets enhanced to a great extent after interface engineering with pentacene film. And, the mechanism was further demonstrated by experiments and DFT calculations detailedly.