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Research on high‐efficiency and cost‐efficient catalysts for oxygen reduction reaction (ORR) is still a vital but challenging issue for commercializing metal–air batteries. Herein, a single‐molecule/atom hybrid catalyst is developed to boost the ORR, in which iron phthalocyanine molecules containing molecular Fe─N4 moieties couple with atomic Co─N4 sites on the surface of polyhedral carbon. Density functional theory calculations reveal that face‐to‐face laminated construction of Fe─N4 and Co─N4 in the hybrid catalyst can effectively modulate the electronic structure of active iron atoms and reduce the energy barrier of the rate‐determining step for ORR. As a result, this hybrid catalyst demonstrates excellent ORR performance, featuring a half‐wave potential of 0.904 V, a peak power density of 238.3 mW cm−2 for zinc–air battery, and outstanding electrocatalytic stability. This work offers a distinctive and robust molecular/atomic engineering approach to creating efficient electrocatalysts, advancing the fields of metal–air batteries. [ABSTRACT FROM AUTHOR]

Activation of metal oxides by light is a robust yet facile approach to manipulating their surface chemistry for favorable reactions with target molecules in heterogeneous catalysis and gas sensors. However, a limited understanding of interface chemistry and the involved mechanism impedes the development of a rational design of oxide interfaces for light‐activated gas sensing. Herein, the TiOx‐assisted photosensitization of In2O3 toward NO2 sensing is investigated as a case study to elucidate the detailed mechanism of light‐activated surface chemistry at the metal/gas interface. The resultant heterogeneous oxides exhibit outstanding NO2 sensing performance under light irradiation thanks to abundant photoexcited electrons and holes that serve as adsorption and desorption sites, respectively, to accelerate both surface reactions. Furthermore, the facile transfer of electrons and holes across the TiOx‐In2O3 interface contributes to improving the reversibility of sensing kinetics. Through this study, the mechanistic understanding is established of how the surface chemistry of metal oxide surfaces can be tuned by light activation providing an effective route to the design fabrication of high‐performance gas sensors. [ABSTRACT FROM AUTHOR]

Due to the unique properties which are considerably different from macro‐scale or bulk materials, 1D) nanostructures have received great interests. In particular, they have greatly contributed to building next‐generation batteries by providing beneficial features such as short ion/electron pathways, structural versatility (i.e., formation of 3D current collectors, free‐standing electrodes, and separators), and excellent stress relaxation. Owing to these definite advantages, 1D nanostructure is often followed by discovery of new electrode materials. This review provides a systematic overview of the state‐of‐the‐art research progresses on 1D nanostructures, which are extensively used for rechargeable batteries. Specifically, a brief introduction of some important 1D nanostructuring methods is started and then, in situ structural characterizations using 1D nanostructures are summarized, which allow a great step forward in atomic‐scale monitoring of reaction kinetics and observing dynamic structural evolution of electrode materials. 1D nanstructuring in solid‐state electrolytes and stabilization of metal anodes are also highlighted which are not only substantially important in current research trends for future batteries but also rarely discussed in previous reviews. At the end, critical perspective and future research direction of 1D nanoengineering for future batteries are suggested. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) have attracted significant interest as gas‐sensing materials due to their unique crystal structure and surface. However, there are still issues when it comes to expanding the types of sensing gases for the TMD gas sensors. To extend gas‐sensing selectivity for the TMD gas sensors in this study, a monolayer (ML) 2D metal–organic framework (MOF) is introduced on top of the PtSe2 gas sensor, thereby tuning the major sensing analyte of PtSe2 from NO2 to H2S. Density functional theory calculations elucidate that the metal species of ML MOFs are attributed to the tuned selectivity of the analytes, based on the difference in binding energies. It is also demonstrated that ML MOF maintained the high responsivity of the pristine PtSe2 even at a low concentration of gas (200 ppb). This is further confirmed through the molecular dynamics simulations, which reveal that the ML feature of the ML MOF is highly essential to preserve the intrinsic ultra‐low limit detection properties of pristine PtSe2. [ABSTRACT FROM AUTHOR]

Thermochromic sensors provide an intuitive and real‐time solution for monitoring the local temperature with naked eyes. Conventional thermochromic sensors often utilize either solution‐type or dense film‐type platforms, which are suboptimal morphologies for exposing a large number of dye molecules to the surface, leading to low sensitivity and sluggish responding speeds. Herein, this article introduces rational synthetic routes to fabricate highly sensitive nanofiber (NF) sensor membranes loaded with thermochromic dyes (C3H6N6·CH2O)x‐loaded nanofibers (NFs) sensor membranes by alignment‐controllable electrospinning techniques (x–y perpendicular and rotary). The NF‐based porous sensor membranes exhibit two‐ to fivefold improved thermochromic sensitivity (ΔRGB) compared to those of dense film‐type sensors at 31.6–42.7 °C. This is attributed to the uniform distribution of dyes throughout the porous NF structure (≈95.7%), which exhibits excellent light transmittance that is 10–30‐fold higher than that of film‐type sensors. Based on the available shape‐conforming synthetic strategies, this article further demonstrates wearable thermochromic sensors in the forms of mask‐, patch‐, and bracelet‐type devices, which can accurately monitor body temperature in real time. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) supported on inorganic materials have attracted much attention in numerous research fields for their high catalytic performance. However, such SACs have been limited by the low metal loading, especially on different types of inorganic supports. Herein, a general approach is presented for preparing SACs on metallic, metal oxide, and perovskite nanosheet (NS) supports to reach a high metal loading of up to 3.94 wt%, by utilizing N‐doped graphene as a sacrificial template that spatially confines the single atoms (SAs). Specifically, the target support material precursors are adsorbed onto the SAs‐stabilized sacrificial template, followed by subsequent heat treatment to transfer the SAs to the support material and to remove the graphene layer. Pt SAs on oxide support exhibits little to no aggregation throughout >10 000 min of annealing at 275 °C, demonstrating high thermal stability, as also supported by ex situ post‐anneal electron microscopy and X‐ray absorption fine structure studies. As a proof‐of‐concept, Pt SACs on SnO2 NSs exhibit high catalytic activity toward chemiresistive sensing of acetone gas (response = 95.4 at 10 ppm, 7.6‐fold enhancement compared with pristine SnO2 NSs) and unprecedented stability under highly humid conditions (27.4% response deterioration at 95% relative humidity). [ABSTRACT FROM AUTHOR]

Designing energy storage devices from thick carbon electrodes with high areal/volumetric energy density via a simple and green way is very attractive but still challenging. Cellulose, as an excellent precursor for thick carbon electrodes with abundant sources and low cost, is usually activated by a chemical activator and pyrolysis route to achieve high electrochemical performance. However, there are still some problems to be addressed, such as the harsh activation conditions, easy collapse of porous structures, and the high cost. Herein, a 3D self‐supporting thick carbon electrode derived from wood‐based cellulose is proposed for high areal and volumetric energy density of supercapacitor from a mild, simple, and green enzymolysis treatment. Benefiting from the high specific surface area (1418 m2 g−1) and abundant active sites on the surface of wood‐derived hierarchically porous structures and enzymolysis‐induced micropores and mesopores, the assembled symmetry supercapacitor from the thick carbon electrode can realize the high areal/volumetric energy density of 0.21 mWh cm−2/0.99 mWh cm−3 with excellent stability of 86.58% after 15 000 long‐term cycles at 20 mA cm−2. Significantly, the simple and universal strategy to design material with high specific surface area, provides a new research idea for realizing multi‐functional application. [ABSTRACT FROM AUTHOR]