Themed collection Special issue in honour of Seth Marder

Jean-Luc Brédas, Zhenan Bao, Thuc-Quyen Nguyen, and Mark E. Thompson introduce the Materials Horizons special issue in honor of Seth Marder.

The origins of the remarkable performance of halide perovskite scintillators are presented, along with solutions to the challenges facing the field, followed by a discussion of applications that will benefit from the unique properties of these materials.

Halide segregation represents a severe stability problem for certain mixed-halide perovskites. Here we explore a myriad of methods for mitigating halide segregation, including several largely unexplored approaches that show significant promise.

Using a feedback loop between computational modeling probing electronic transitions and experimental work, the colors, transmissivity, and redox switching properties of a family of anodically coloring electrochromic molecules are reviewed.

This Mini-review highlights reconfigurable nanowrinkles based on polymer skin layers and how they enable hierarchical structuring of thin functional materials.

Inorganic–organic interfaces: a tutorial on using organic functional groups to enhance the performances and/or enable new functionality of inorganic nanomaterials.

An effective framework for the band engineering in 2D covalent organic frameworks is revealed by describing the fundamental relationships among the electronic structures, the lattice symmetries, and the frontier molecular orbitals of building units.

The effects of mixing in organic photovoltaics are unclear partly due to challenges in characterization. X-Ray and neutron scattering techniques have been successful in quantifying mixing but meet new challenges with emerging non-fullerene systems.

Plasmons have been widely studied over the past several decades because of their ability to strongly absorb light and localize its electric field on the nanoscale, leading to applications in spectroscopy, biosensing, and solar energy storage.

Metal halide perovskites exhibit complex electronic properties. The presently identified fundamental concepts and phenomena governing the electronic behavior of this material class are addressed in this article.

Organic photodetectors can achieve narrowband photodetection within a single optoelectronic device. This comprehensive review summarizes and compares the different approaches, introduces their application fields, and outlines current challenges.

This review summarizes the fabrication technology and recent progress of large-area organic solar cells based on non-fullerene electron acceptors.

This review summarizes the recent advances in thermoresponsive supramolecular assemblies and the molecular level factors and parameters that can be tuned to achieve optimal responses for a variety of applications.

This review summarizes the main concepts, recent developments, and several strategies for mimicking sensory adaptation; challenges and perspectives in this emerging field are also proposed.

This review summarizes recent progress in the occurrence, mechanism and application for some of the materials with optical properties that are significantly improved through polymerization.

This review summarizes the strategies for improving the crystallinity of covalent organic frameworks and conjugated polymers. The strategies include planarity modulation, fluorine substitution, side chain engineering, and so on.

This review highlights recently developed biological applications of triarylboranes in cell imaging and as sensors for DNA, RNA, proteins, and bio-relevant small molecules using 1- and 2-photon excited fluorescence, Raman, and SERS.

We review the design and fabrication of selective chemical sensors based on low-dimensional materials functionalized with (supra)molecular receptors, from the choice of the analyte of interest to its final device integration.

This review comprehensively summarizes fundamentals and potential applications of molecular martensites – an emerging class of dynamic crystals for next-generation smart functional materials.

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS, has been widely used as an effective hole transporting material in many different organic semiconductor devices for well over a decade.

A systematic comparison between electrochemical and organic bioelectronic sensors reveals a unified rational description for a transistor amplified detection.

Ambipolar transistors, i.e. transistors with symmetrical n- and p-type performances, open new avenues for the design and integration of high-density, efficient and versatile circuits for advanced technologies.

New fabrication approaches for mechanically flexible implants hold the key to advancing the applications of neuroengineering in fundamental neuroscience and clinic.

Propylene and butylene glycol oligoether chains have been employed as alternatives to ethylene glycol in thiophene based semiconductors for OECTs. Their impact on electrochemical, microstructure, and swelling properties are discussed.

Polymer–dopant intermolecular interactions characterized by solid-state NMR and EPR spectroscopy techniques offer clues about the different doping mechanisms and efficiencies.

A systematic analysis of the phonon bands calculated using dispersion-corrected density functional theory for crystalline acenes reveals analogies between the phonons and classical oscillator models. Based on these, the evolution of the materials’ properties can be rationalised.

2D hydrazone-linking covalent organic frameworks with differently sized crown ether side chains were synthesized, and 20-fold improved emission was achieved by tuning the size of the crown ethers.

Molecular doping is the key to enabling organic electronic devices, however, the design strategies to maximize doping efficiency demands further clarity and comprehension.

The anharmonicity of the Ruddlesden Popper metal-halide lattice, and its consequences for their electronic and optical properties, are paramount in their basic semiconductor physics.

In situ terahertz spectroscopy on electrochemically doped P3HT reveals the impact of polarons and bipolarons on the short-range conductivity.

Chemical and ionic interactions between an ionic liquid and printable semiconductors are probed by photoelectron spectroscopy, with increasing reactivity associated with underlying defects from P3HT to NiO_x to PbS/PbI_x quantum dots to MAPbI₃.

Dual purposed ZnO tetrapods promote photopolymerization of methacrylates and provide surface roughness for superhydrophobicity. Large area photochemical fabrication of hybrid coating is demonstrated for liquid/liquid separation applications.

Molecular doping of a polythiophene with oligoethylene glycol side chains is found to strongly modulate not only the electrical but also the mechanical properties of the polymer.

Marcus theory explains photoinduced electron transfer from donor molecules to a fullerene host when all microstates are included, and formation of free charge competes with charge-transfer states.

A stacking scheme for solution-processable electrochromic polymers is presented with the integration of direct photolithography patterning to realize full colors, layered textures, and controllable color switching.

We report a F-doped FeNC catalyst with improved ORR performance. The enhanced performance is associated with the large BET surface area, abundant single Fe atoms, and strong electron-withdrawing F-doping.

Nanoparticle dispersions were studied by cryogenic electron tomography, which was found to allow extraction of key thermodynamic quantities.

Starting from a chiral resolution of 2-ethylhexanoic acid followed by conversions of functional groups without interfering with the enantiopurity, we have successfully introduced an enantiopure 2-ethylhexyl group on to dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT) via a Negishi-coupling reaction to synthesize 2-(R)-(2-ethylhexyl)- and 2-(S)-(2-ethylhexyl)-DNTT (R- and S-EH-DNTT, respectively).

We investigate triplet pair dynamics in pentacene dimers that have varying degrees of coplanarity (pentacene–pentacene twist angle).

Polymorphism in organic charge-transfer complexes induces a variation in electronic structure and sub-gap states which directly impact device physics. Single crystals are highly ordered, allowing for the measurement with reduced extrinsic factors.

We demonstrate proof-of-concept refractive-index structures with large refractive-index-gradient profiles, using a rapid micro-contact photothermal annealing (μCPA) process to pattern a novel organic/inorganic hybrid materials family.

Single-crystals of a series of Bz-based NFAs derivatized via regiospecific N-alkyl engineering have been systematically studied. The J-aggregate-like packing in EHN6SEH-4F facilitates formation of ordered 3D channels for efficient charge transport.

Organic molecules usually exhibit optical gain losses in the NIR, due to the absorption of charged species/triplets. We report on a nanographene molecule in which the minimisation of such losses enable the achievement of low-threshold NIR lasing.

By tuning donor strength, we produce an organic electro-optic chromophore with high hyperpolarizability, low absorption, and excellent electro-optic activity, which is demonstrated in a plasmonic–organic hybrid modulator with near record low V_πL.

A robust, soft material held together by charge transfer interactions is developed. The nanostructure dimensions and material properties can be tuned by molecular design or pressure.

A biocompatible supercapacitor has been assembled by incorporating crystalline tetra-aniline as active electrode material via chloride electrochemical interaction.

We report a versatile method to prepare intercalated transition metal dichalcogenides in a thin-film morphology. Metallocenes, alkylamines, and electron-proton transfer mediators are intercalated into MoS₂ and WS₂ using vacuum filtration.

Multi-photoresponsive properties, including photochromism, photodeformation and room temperature phosphorescence, are achieved in triphenylethylene derivatives, which can be well tuned by variation of bromine substituents to phenyl moieties.

A new class of yellow- to red-emitting carbazolylgold(III) complexes containing isomeric thienopyridine and thienoquinoline moieties in the cyclometalating ligand has been designed to realize high performance OLEDs with long operational lifetime.

Highly efficient non-doped blue TTU-OLEDs were realized based on the AIEgens with excellent emission and upconversion efficiency in the film states.

Custom-built flow cells for absorption and fluorescence spectroelectrochemistry provide details on optical transitions, transition dipole moments and fluorescence quantum yields of five perylene bisimides as well as their radical anions and dianions.

Phosphorescent organic light-emitting diodes (PhOLEDs) are leading candidates for displays or lighting technologies.

A printable ink composed of a photoactive cationic conjugated polymer (PPV) and gelatin/alginate/hyaluronic acid was developed for 3D printing artificial skin patches with the biofunctions of anti-infection and augmenting wound repair.

An emissive yet charge-generating organic donor/acceptor blend is demonstrated, which highlights the importance of electronic hybridization between the charge-transfer and local-exciton states to reduce non-radiative recombination loss.

Pyrene moieties inserted among acene units do not result in long acene-like structures; rather the pyrene-inserted acene structure is, electronically, a series of (nearly) isolated acenes.

Post-processing the active layer in additive-free organic solar cells enabled an enhancement in performance due to an increased acceptor crystallinity, resulting in a fill factor of 76%, a power conversion efficiency of 13.84% and an improved stability.

Herein, capsule shells containing hindered urea bonds were prepared using interfacial polymerization in an oil-in-oil Pickering emulsion stabilized by functionalized graphene oxide nanosheets.

Organic solar cell morphology evolution through distinct and consecutive spinodal decomposition and nucleation and growth mechanisms.

Blade coating of mixed cation, mixed halide perovskite films is investigated using in situ X-ray scattering to investigate the role of formulations and processing routes and eliminate the need for anti-solvent dripping.

Experimental studies of electron transport through an edge-fused porphyrin oligomer in a graphene junction are interpreted within a Hubbard dimer framework.

We present a combined experimental and theoretical study of small saturated heterocyclic alkanes and show that they perform well as insulators with an electronic transmission that is suppressed due to destructive interference.

In an effort to design deep-blue light emitting materials for use in OLEDs, the optical and electronic properties of a series of tetraarylbenzobis[1,2-d:4,5-d′]oxazole (BBO) cruciforms were evaluated using density functional theory (DFT) and time-dependent DFT (TD-DFT).

The factors influencing negative wavelength dispersion are investigated for a series of benzodithiophene based photopolymerisable liquid crystals.

The fundamental structure–property relationships in the Cs_yFA_1−yPb(Br_xI_1−x)₃ compositional space are reported.

We study the phase behavior of hybrid organic–inorganic metal-halide perovskite and propose a simple method to assess heterogeneity in the <100 nm length scales.

The energy transfer, PLQY, charge mobility, and OLED performance of blend films of first generation Ir(ppy)₃-cored light-emitting dendrimers and dendrimeric TCTA-based hosts are found to be dependent on the dendrons and surface groups used.

A 3D co-cultured organotypic cancer model to evaluate the anti-metastatic ability of siRNA loaded BSA decorated PICs nanoparticles has been developed.

Two platinum complexes PBSNND and AtFNND have been used to achieve high efficiency (EQE_max of 12.9% and 13.7%) hybrid white OLEDs with an ultrathin and singly doped phosphorescence emitting layer, respectively.

Designing OECTs to amplify chemical redox reactions reliably requires: (1) separating reaction from the OECT (2) operating the OECT potentiometrically (3) utilizing non-polarizable gate electrode (4) maximizing transconductance of channel material.

It is discovered that the negative effects on OER activity caused by the stabilization of NPs with surface-capping polymers can be mitigated by decreasing the grafting density or increasing the hydrophilicity of the polymer chains.