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Owing to the inertness of CO2 molecules, the development of highly active photocatalysts for CO2 reduction reactions (CO2RR) remains a formidable challenge. Here, we designed an MXene-based single-atom Fe co-catalyst (Fe1/Ti3−xC2Ty) featuring fast Ti–Fe electron channels to achieve enhanced CO2RR performance. The synthesized Fe1/Ti3−xC2Ty exhibited a CO yield of 259.0 μmol g−1 h−1 without the addition of any organic sacrificial agents. The experimental and computational results reveal that, electrons transfer from Ti to Fe and then accumulate at the active sites, which facilitates the transfer of charges and enhances the activation of CO2 molecules. This work provides a new direction of MXene-based non-noble-metal monoatomic catalysts for efficient photoreduction of CO2 under gas–solid photocatalytic conditions with pure water. [ABSTRACT FROM AUTHOR]

Room-temperature sodium–sulfur (RT Na–S) batteries have the drawbacks of the poor shuttle effect of soluble sodium polysulfides (NaPSs) as well as slow sulfur redox kinetics, which result in poor cycling stability and low capacity, seriously affecting their extensive application. Herein, defect engineering is applied to construct rich oxygen vacancies at the interface of a TiO2 anatase/rutile homojunction (OV-TRA) to enhance sulfur affinity and redox reaction kinetics. Combining structural characterizations with electrochemical analysis reveals that OV-TRA well alleviates the shuttle effect of NaPSs and precipitates the deposition and diffusion kinetics of Na2S. Consequently, S/OV-TRA provides excellent electrochemical performance with a reversible capacity of 870 mA h g−1 at 0.1 C after 100 cycles and a long-term cycling capability of 759 mA h g−1 at 1 C after 1000 cycles. This work provides an effective interfacial defect engineering strategy to promote the application of metal oxides in RT Na–S batteries. [ABSTRACT FROM AUTHOR]

Mesoporous nitrogen-doped carbon-anchored single atom Zn was synthesized through etching of ZIF-8 with 1,10-phenanthroline and subsequent pyrolysis based on the Kirkendall effect. The abundant pores and increased surface area promote CO2 adsorption and mass transfer, thus significantly improving the catalytic activity in solvent-free cycloaddition of epoxides with CO2. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into multi-carbon (C2+) products (e.g. C2+ alcohols) offers a promising way for CO2 utilization. Use of strong alkaline electrolytes is favorable to producing C2+ products. However, CO2 can react with hydroxide to form carbonate/bicarbonate, which results in low carbon utilization efficiency and poor stability. Using acidic electrolyte is an efficient way to solve the problems, but it is a challenge to achieve high selectivity of C2+ products. Here we report that the amine modified copper nanoparticles exhibit high selectivity of C2+ products and carbon utilization at acidic condition. The Faradaic efficiency (FE) of C2+ products reach up to 81.8% at acidic media (pH=2) with a total current density of 410 mA cm-2 over n-butylamine modified Cu. Especially the FE of C2+ alcohols is 52.6%, which is higher than those reported for CO2 electroreduction at acidic condition. In addition, the single-pass carbon efficiency towards C2+ production reach up to 60%. Detailed studies demonstrate that the amine molecule on the surface of Cu cannot only enhance the formation, adsorption and coverage of *CO, but also provide a hydrophobic environment, which result in the high selectivity of C2+ alcohols at acidic condition., (© 2024 Wiley‐VCH GmbH.)

Room-temperature sodium-sulfur (RT Na-S) batteries have the drawbacks of the poor shuttle effect of soluble sodium polysulfides (NaPSs) as well as slow sulfur redox kinetics, which result in poor cycling stability and low capacity, seriously affecting their extensive application. Herein, defect engineering is applied to construct rich oxygen vacancies at the interface of a TiO 2 anatase/rutile homojunction (O V -TRA) to enhance sulfur affinity and redox reaction kinetics. Combining structural characterizations with electrochemical analysis reveals that O V -TRA well alleviates the shuttle effect of NaPSs and precipitates the deposition and diffusion kinetics of Na 2 S. Consequently, S/O V -TRA provides excellent electrochemical performance with a reversible capacity of 870 mA h g -1 at 0.1 C after 100 cycles and a long-term cycling capability of 759 mA h g -1 at 1 C after 1000 cycles. This work provides an effective interfacial defect engineering strategy to promote the application of metal oxides in RT Na-S batteries.

Hetero-interface engineering has been widely employed to develop supported multicomponent catalysts for water electrolysis, but it still remains a substantial challenge for supported single atom alloys. Herein a conductive oxide MoO 2 supported Ir 1 Ni single atom alloys (Ir 1 Ni@MoO 2 SAAs) bifunctional electrocatalysts through surface segregation coupled with galvanic replacement reaction, where the Ir atoms are atomically anchored onto the surface of Ni nanoclusters via the Ir-Ni coordination accompanied with electron transfer from Ni to Ir is reported. Benefiting from the unique structure, the Ir 1 Ni@MoO 2 SAAs not only exhibit low overpotential of 48.6 mV at 10 mA cm -2 and Tafel slope of 19 mV dec -1 for hydrogen evolution reaction, but also show highly efficient alkaline water oxidation with overpotential of 280 mV at 10 mA cm -2 . Their overall water electrolysis exhibits a low cell voltage of 1.52 V at 10 mA cm -2 and excellent durability. Experiments and theoretical calculations reveal that the Ir-Ni interface effectively weakens hydrogen binding energy, and decoration of the Ir single atoms boost surface reconstruction of Ni species to enhance the coverage of intermediates (OH*) and switch the potential-determining step. It is suggested that this approach opens up a promising avenue to design efficient and durable precious metal bifunctional electrocatalysts., (© 2023 Wiley-VCH GmbH.)

Mesoporous nitrogen-doped carbon-anchored single atom Zn was synthesized through etching of ZIF-8 with 1,10-phenanthroline and subsequent pyrolysis based on the Kirkendall effect. The abundant pores and increased surface area promote CO 2 adsorption and mass transfer, thus significantly improving the catalytic activity in solvent-free cycloaddition of epoxides with CO 2 .