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As a two-dimensional (2D) inorganic molecular van der Waals crystal, Sb2O3 has been widely recognized as an excellent dielectric and encapsulation material due to its wide bandgap, high dielectric constant (κ), and remarkably high air stability. Considering the significance and potential application of Sb2O3 in future electronic devices, it is valuable to summarize its recent advancements. In this review, we present the latest progress on 2D Sb2O3 flakes and films, encompassing synthesis methods, physical properties, and device applications. First, preparation strategies such as chemical vapor deposition, vertical physical vapor deposition, thermal evaporation deposition, liquid metal synthesis, and atomic layer deposition growth routes are highlighted. Subsequently, the mechanical properties and the phase transition mechanisms of 2D Sb2O3 are presented. Moreover, device applications, including encapsulation layer, photodetector, and gate dielectric, are demonstrated. Finally, we outline the future challenges and research priorities of 2D Sb2O3 materials. [ABSTRACT FROM AUTHOR]

H2O2 photosynthesis coupled with biomass valorization can not only maximize the energy utilization but also realize the production of value‐added products. Here, a series of COFs (i.e. Cu3‐BT‐COF, Cu3‐pT‐COF and TFP‐BT‐COF) with regulated redox molecular junctions have been prepared to study H2O2 photosynthesis coupled with furfuryl alcohol (FFA) photo‐oxidation to furoic acid (FA). The FA generation efficiency of Cu3‐BT‐COF was found to be 575 mM g−1 (conversion ≈100 % and selectivity >99 %) and the H2O2 production rate can reach up to 187 000 μM g−1, which is much higher than Cu3‐pT‐COF, TFP‐BT‐COF and its monomers. As shown by theoretical calculations, the covalent coupling of the Cu cluster and the thiazole group can promote charge transfer, substrate activation and FFA dehydrogenation, thus boosting both the kinetics of H2O2 production and FFA photo‐oxidation to increase the efficiency. This is the first report about COFs for H2O2 photosynthesis coupled with biomass valorization, which might facilitate the exploration of porous‐crystalline catalysts in this field. [ABSTRACT FROM AUTHOR]

The efficient CO2 electroreduction into high‐value products largely relies on the CO2 adsorption/activation or electron‐transfer of electrocatalysts, thus site‐specific functionalization methods that enable boosted related interactions of electrocatalysts are much desired. Here, an oriented coordination strategy is reported to introduce N‐rich auxiliary (i.e., hexamethylenetetramine, HMTA) into metalloporphyrin metal organic frameworks (MOFs) to synthesize a series of site‐specific functionalized electrocatalysts (HMTA@MOF‐545‐M, M = Fe, Co, and Ni) and they are successfully applied in light‐assisted CO2 electroreduction. Noteworthy, thus‐obtained HMTA@MOF‐545‐Co presents approximately two times enhanced CO2 adsorption‐enthalpy and electrochemical active surface‐area with largely decreased impedance‐value after modification, resulting in almost twice higher CO2 electroreduction performance than its unmodified counterpart. Besides, its CO2 electroreduction performance can be further improved under light‐illumination and displays superior FECO (≈100%), high CO generation rate (≈5.11 mol m−2 h−1 at −1.1 V) and energy efficiency (≈70% at −0.7 V). Theoretical calculations verify that the oriented coordination of HMTA can increase the charge density of active sites, almost doubly enhance the CO2 adsorption energy, and largely reduce the energy barrier of rate determining step for the boosted performance improvement. This work might promote the development of modifiable porous crystalline electrocatalysts in high‐efficiency CO2 electroreduction. [ABSTRACT FROM AUTHOR]

The full reaction photosynthesis of H2O2 that can combine water‐oxidation and oxygen‐reduction without sacrificial agents is highly demanded to maximize the light‐utilization and overcome the complex reaction‐process of anthraquinone‐oxidation. Here, a kind of oxidation‐reduction molecular junction covalent‐organic‐framework (TTF‐BT‐COF) has been synthesized through the covalent‐coupling of tetrathiafulvalene (photo‐oxidation site) and benzothiazole (photo‐reduction site), which presents visible‐light‐adsorption region, effective electron‐hole separation‐efficiency and photo‐redox sites that enables full reaction generation of H2O2. Specifically, a record‐high yield (TTF‐BT‐COF, ≈276 000 μM h−1 g−1) for H2O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation‐reduction molecular junction COFs for full reaction photosynthesis of H2O2, which might extend the scope of COFs in H2O2 production. [ABSTRACT FROM AUTHOR]

The full reaction photosynthesis of H2O2 that can combine water‐oxidation and oxygen‐reduction without sacrificial agents is highly demanded to maximize the light‐utilization and overcome the complex reaction‐process of anthraquinone‐oxidation. Here, a kind of oxidation‐reduction molecular junction covalent‐organic‐framework (TTF‐BT‐COF) has been synthesized through the covalent‐coupling of tetrathiafulvalene (photo‐oxidation site) and benzothiazole (photo‐reduction site), which presents visible‐light‐adsorption region, effective electron‐hole separation‐efficiency and photo‐redox sites that enables full reaction generation of H2O2. Specifically, a record‐high yield (TTF‐BT‐COF, ≈276 000 μM h−1 g−1) for H2O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation‐reduction molecular junction COFs for full reaction photosynthesis of H2O2, which might extend the scope of COFs in H2O2 production. [ABSTRACT FROM AUTHOR]

Strategy that can design powerful photothermal‐catalysts to achieve photothermal‐effect assisted coupling‐catalysis is much desired for the improvement of energy conversion efficiency and redox product value in CO2 electroreduction system. Herein, a kind of bifunctional viologen‐containing covalent organic framework (Ni‐2CBpy2+‐COF) has been prepared and successfully applied in photothermal‐assisted co‐electrolysis of CO2 and methanol. Specifically, the FECO (cathode) and FEHCOOH (anode) for Ni‐2CBpy2+‐COF can reach up to ≈100 % at 1.9 V with ≈31.5 % saved overall electricity‐consumption when the anodic oxygen evolution reaction (OER) is replaced by methanol oxidation. The superior performance could be attributed to the cyclic diquats in Ni‐2CBpy2+‐COF that enhance the photothermal effect (ΔT=49.1 °C) to accelerate faster charge transfer between catalyst and immediate species as well as higher selectivity towards desired products as revealed by DFT calculations and characterizations. [ABSTRACT FROM AUTHOR]

Light‐assisted Li–CO2 battery, emerging as a powerful battery‐technology to utilize light‐energy, has attracted much attention yet it is still limited by the lack of efficient photocathode catalysts toward simultaneously promoted CO2 activation/evolution processes. Here, a kind of phthalocyanine‐based metal–organic framework nanosheet (CoPc–Mn–O) is prepared and applied as efficient photocathode catalyst in light‐assisted Li–CO2 battery. Thus‐produced CoPc–Mn–O shows nanosheet‐morphology (≈1 nm), dual active metal‐sites (i.e., Co–N4 and Mn–O4), high conductivity, and photosensitivity. The resulting battery delivers a high round‐trip efficiency of 98.5% with an ultralow voltage hysteresis of 0.05 V and superior cycling‐stability (81.3%) for 60 h at 0.02 mA cm−2, which is represented to be one of the best photo‐cathodes to date. Density functional theory calculations and characterizations prove that the presence of photosensitive CoPc–Mn–O with dual active metal‐sites endows an activation energy (3.2 eV) for CO2 activation under light condition and simultaneously promote the CO2 evolution to enhance the battery efficiency. [ABSTRACT FROM AUTHOR]

Hybrid CO2 electroreduction (HCER) is recognized as an important strategy to improve the total value of redox products and energy conversion efficiency. In this work, a coordination catalyst model system (Ni8‐TET with active oxidation sites, Ni‐TPP with active reduction sites and PCN‐601 with redox‐active sites) for HCER was established for the first time. Especially, PCN‐601 can complete both anodic methanol oxidation and cathodic CO2 reduction with FEHCOOH and FECO over 90 %. The performance can be further improved with light irradiation (FE nearly 100 %). DFT calculations reveal that the transfer of electrons from NiII8 clusters to metalloporphyrins under electric fields results in the raised oxidizability of Ni8 clusters and the raised reducibility of metalloporphyrin, which then improves the electrocatalytic performance. This work serves as a well‐defined model system and puts forward a new design idea for establishing efficient catalysts for hybrid CO2 electroreduction. [ABSTRACT FROM AUTHOR]