Materials Chemistry Frontiers最新文献

Electrochemical nitrate reduction to ammonia (NRA) is an emerging sustainable technology that converts nitrate contamination in wastewater into the value-added chemical ammonia. Copper-based catalysts represent one of the most competitive non-noble NRA electrocatalysts due to their robust nitrate adsorption capability. In this study, we developed a series of Bi–Cu bimetallic oxides (BiCuO_x) with mixed oxidation states of Cu and Bi by tuning the surface oxygen vacancy (O_V) content via a one-pot solution-based in situ H*-mediated reduction method. The resulting BiCuO_x catalyst exhibits an enlarged surface area, abundant electrochemically active sites, and optimized O_V concentration, delivering a high NH₃ faradaic efficiency (FE) of 92.27% ± 3.47% and an NH₃ yield rate of 4331.25 ± 208.4 μg h⁻¹ mg_cat.⁻¹ at −0.8 V vs. RHE. Theoretical calculations reveal that the as-obtained BiCuO_x catalyst more effectively suppresses NO₂* intermediate poisoning on its surface compared to the single-component Cu catalyst owing to the favorable orbital hybridization between the intermediates and the catalyst surface, thereby facilitating the subsequent steps in the NRA reaction pathway. Furthermore, a zinc–nitrate battery is designed by integrating a BiCuO_x cathode with a zinc plate anode sourced from spent zinc–carbon batteries, achieving a peak power density of 1.706 mW cm⁻² and an NH₃ FE of 82.31%. This study highlights a low-cost and highly active oxygen vacancy-mediated catalyst for electrochemical NRA through one-pot solution synthesis, promoting green ammonia production via sustainable NRA.

Purely organic circularly polarized phosphorescence (CPP) materials are promising candidates for chiral optoelectronic and photonic applications but remain limited by challenges in achieving both high quantum efficiency and strong dissymmetry. Here, we report a high-performance CPP system based on brominated cholesteric liquid-crystalline (CLC) molecules that spontaneously self-assemble into left-handed chiral nematic (N*) phases. Among the series, Br10Ch exhibits bright blue CPP at 450 nm with a phosphorescent quantum yield of 36% and a dissymmetry factor of g_lum = +0.30, enabled by enhanced spin–orbit coupling and long-range helical ordering that suppress non-radiative decay. Furthermore, doping the N* matrix with an achiral fluorescent dye (8CNS) enables triplet-to-singlet Förster resonance energy transfer, yielding green circularly polarized fluorescence at 502 nm with inverted handedness (g_lum = −0.32) via selective reflection within the cholesteric host. This combined color tunability and handedness switching in a purely organic system provides a modular approach for tailoring chiroptical emission without heavy metals. Our findings establish CLCs as versatile supramolecular scaffolds for high-performance CPP, offering new opportunities for dynamic optical control in displays, data encryption, and advanced photonic devices.

Boron-based room-temperature phosphorescence (RTP) materials have garnered considerable attention due to their unique photophysical properties and diverse application potential. Nevertheless, systematic discussion on the design strategies, excited state control mechanisms, and practical applications of such molecules remains scarce. This review systematically analyzes the structure–property relationships in boron-based RTP materials, focusing on the influence of key structural factors such as their coordination modes, the number and position of substituents, and the design of host–guest systems. These factors enable precise control over the phosphorescence lifetime and the emission wavelength of the materials. Boron-based RTP materials demonstrate promising applications particularly in anti-counterfeiting, light-emitting displays, and biological imaging. Moreover, this review outlines future research directions and challenges, offering a theoretical foundation for the development of novel RTP materials.

A series of donor–oxygen–acceptor (D–O–A)-type polymers have been newly designed and synthesized, where benzophenone, 1,3-bis(phenylmethanone)-phenylene or 1,4-bis(phenylmethanone)-phenylene is selected as the acceptor combined with the acridine donor through an oxygen linkage. The characteristic geometry endows them with obvious phosphorescence at room temperature for both the neat and doped films. Meanwhile, their emission colors can be finely tuned with increasing electron withdrawing ability of the acceptor. As a consequence, the corresponding polymer light-emitting diodes achieve a bright sky-blue, green and yellow electroluminescence peaking at 482, 502 and 547 nm, respectively. The color modification via acceptor engineering clearly highlights the great universality and potential of the D–O–A design for efficient pure organic room-temperature electrophosphorescent polymers.

Purely organic room-temperature phosphorescence (RTP) materials show broad prospects for various applications due to their characteristics such as stimuli-responsiveness and high exciton utilization. A key challenge for improving the performance of purely organic RTP materials lies in suppressing non-radiative decay while enhancing spin–orbit coupling (SOC). To this end, we systematically combined benzophenone (BP) with thianthrene (TA) at different modification sites and with varying numbers of substituents, creating a class of high-efficiency RTP materials by leveraging the folded conformation of TA groups and introducing intramolecular charge transfer (ICT) to enhance SOC. Benefiting from the separated fluorescence–RTP dual emission of these materials, highly sensitive ratiometric optical oxygen sensing can be achieved with a Stern–Volmer coefficient of up to 10.65 kPa⁻¹. This study not only deepens the understanding of the structure–property relationship of TA-based RTP materials but also provides an effective strategy for performance enhancement and functional development of purely organic RTP materials.

An asymmetric indenone-fused tetraazatetracene based bent N-heteroarene is designed and synthesized. Its photophysical and electrochemical properties together with the packing structure are studied, and its charge transport properties in organic field-effect transistors are investigated. Structure–property relationships are illustrated through comparison with other reported asymmetric N-heteroarenes.

The Materials Chemistry Frontiers Emerging Investigators Series highlights the best research being conducted by scientists in the early stages of their independent careers. This editorial features the emerging investigators who contributed to this series in 2024. Each contributor was recommended as carrying out work with the potential to influence future directions in materials chemistry. Congratulations to all the researchers, we hope you enjoy reading their work.

In single-molecule junctions, quantum interference (QI) effects manifest even at room temperature and can be explained by simple quantum circuit rules (QCR), and a rather intuitive magic ratio (MR), theory. These rules characterise how individual moieties contribute to the overall electrical conductance (G), of a molecule and how the overall G can change when the connectivities between different moieties is varied. Here we examine the electrical conductance of a single-ferrocene junction when the two metal electrodes connect to both upper and lower cyclopentadienyl (CP) rings and compare this with the conductance when both electrodes are contacted to only the upper CP ring. In the case of the former, the angle of rotation θ between the upper and lower rings could be changed by varying the distance between the electrodes. The main aim of our investigation is to determine how QI within the ferrocene core is affected by the length of linker groups, which connect the core to electrodes. We find that when θ = 0, short and long molecules exhibit destructive QI (DQI) features within the HOMO–LUMO gap, whereas as θ is increased, the DQI is alleviated. However, DQI within the HOMO–LUMO gap is alleviated at entirely different rotation angles of θ >20° for the molecule with longer linkers, compared to >60° for the shorter molecule. This shows that interference patterns within the ferrocene core are not simply a property of the core alone, but are a holistic property of the molecule as a whole. We investigated the Seebeck coefficients S of these molecules and found that S of the longer molecules can reach 250 μV K⁻¹, which is significantly higher that the Seebeck coefficients of the shorter molecules.

Developing stretchable electromagnetic interference (EMI) shielding materials is highly desirable for integrated flexible electronic devices, because they often suffer from the decrease of EMI shielding effectiveness (SE) under large tensile deformation. Combining elastic polymers and liquid metals (LM) together may provide a promising solution. However, it is still a great challenge to understand how to avoid the leakage of LM under tensile deformation. Herein, layer-by-layer thermoplastic polyurethane/liquid metal (TPU–LM) composite films with a nanofiber–LM interlocked structure are prepared. The porous TPU nanofibers provide a supporting skeleton with high mechanical properties to encapsulate the LM to avoid its leakage, and the LM layers can therefore maintain a continuous conductive network when it is stretched significantly. As a result, the TPU–LM composite film not only exhibits high EMI SE and anti-leakage performance under large tensile deformation, but also presents excellent chemical resistance, high/low-temperature resistance (−196 to 100 °C), self-cleaning and temperature-visualizing performances, indicating potential applications in flexible wearable electronic devices with large deformation. In short, the composite films with a nanofiber–LM interlocked structure not only provide a promising solution to avoid the leakage of LM in practical applications, but can also be used in self-cleaning and temperature-visualizing multifunctional applications.

Deuteration of Pt(II) complexes not only enhances their chemical stability but also broadly influences their phosphorescence. Herein, we examine these isotope effects, which exhibit site-dependent variations. Deuterated complexes display noticeable deceleration in spin-converted intersystem crossing and phosphorescent transitions, revealing a non-ignorable hyperfine coupling effect derived from the change in the nuclear magnetic moments of hydrogen atoms. The variations in emission vibrational peaks, investigated via both experimentation and computation, are strongly correlated with the changes in the kinetics of the high-frequency coupling modes exerted by site-selective deuteration. Moreover, deuteration suppresses triplet exciton-vibration coupling, which significantly reduces non-radiative decay rates and results in higher emission quantum yields. By effectively utilizing the site effect through selective deuteration, the photo-/electro-luminescent efficiencies of Pt-d¹_py are improved, along with its blue color purity. Furthermore, a device based on Pt-d¹_py demonstrates a twofold increase in the operational lifetime. We anticipate that these insights can enhance the development of organic materials at a subatomic level, leading to significant improvements in device performance.