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Single atomic catalysts (SACs) offer a superior platform for studying the structure–activity relationships during electrocatalytic CO2 reduction reaction (CO2RR). Yet challenges still exist to obtain well‐defined and novel site configuration owing to the uncertainty of functional framework‐derived SACs through calcination. Herein, a novel Bi−N2O2 site supported on the (1 1 0) plane of hydrogen‐bonded organic framework (HOF) is reported directly for CO2RR. In flow cell, the target catalyst Bi1‐HOF maintains a faradaic efficiency (FE) HCOOH of over 90 % at a wide potential window of 1.4 V. The corresponding partial current density ranges from 113.3 to 747.0 mA cm−2. And, Bi1‐HOF exhibits a long‐term stability of over 30 h under a successive potential‐step test with a current density of 100–400 mA cm−2. Density function theory (DFT) calculations illustrate that the novel Bi−N2O2 site supported on the (1 1 0) plane of HOF effectively induces the oriented electron transfer from Bi center to CO2 molecule, reaching an enhanced CO2 activation and reduction. Besides, this study offers a versatile method to reach series of M−N2O2 sites with regulable metal centers via the same intercalation mechanism, broadening the platform for studying the structure–activity relationships during CO2RR. [ABSTRACT FROM AUTHOR]

Developing an efficient, interface-rich, and free-standing non-noble-metal electrocatalyst is vital for the flexible zinc-air batteries (ZABs). Herein, a three-dimensional (3D) heterogeneous carbon-based flexible membrane was assembled by Co@carbon nanosheets/carbon nanotubes and hollow carbon nanofiber (Co@NS/CNT-CNF) as an efficient oxygen reduction reaction (ORR) catalyst with a positive half-wave potential of 0.846 V and a small Tafel slope of 79 mV·dec−1. Meanwhile, the Co@NS/CNT-CNF electrode also exhibits excellent open-circuit voltage, peak power density, and long-time cycling stability in liquid-state ZABs (1.605 V, 163 mW·cm−2, and 400 h) and flexible ZABs under flat/bending condition (1.47 V, 102 mW·cm−2, and 80 h). Such heterogeneous flexible membrane architecture not only optimizes the electrolyte infiltration, but also provides capacious possibility for O2 and electrolyte transfer. Meanwhile, work-function analyses coupled with density functional theory (DFT) results demonstrate that the electron transfer capability and metal—support interaction can be well optimized in the obtained Co@NS/CNT-CNF catalyst. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of the four-electron-proton coupled oxygen evolution reaction (OER) limits the efficiency of water splitting. Herein, Ni–S–CoFe 2 O 4 magnetic nanosheets supported on Ni Foam (Magn-Ni-S-CoFe 2 O 4 /NF) as highly active OER electrocatalysts are synthesized via an extremely simple magnetic-field guided co-electrodeposition strategy. With the application of magnetic fields, the flower-like structures consisting of numerous nanosheets are obtained. This special interconnected structure can effectively reduce the transfer resistance to electrons during catalysis. The ultra-thin amorphous Ni–S layer at the edge of well-defined crystalline CoFe 2 O 4 provides more active sites for the reaction because of the abundant defects, which greatly enhances the OER performance. At the same time, the application of magnetic fields changes the chemical state of the electrocatalyst. The well-designed Magn-Ni-S-CoFe 2 O 4 /NF exhibits excellent OER activity with a low overpotential of 228 mV at the current density of 10 mA cm−2, which is lower than the value of 253 mV for the Ni–S–CoFe 2 O 4 /NF without applied magnetic field, a small Tafel slope of 72 mV dec−1 and excellent stability for at least 24 h. This work provides a simple magnetic field-assisted synthesis method to prepare electrocatalysts with excellent OER activity. • A new highly active and cost-effective electrocatalyst: Magn-Ni-S-CoFe 2 O 4 /NF. • An innovative synthesis method: electrodeposition assisted by magnetic field. • A excellent electrocatalytic activity of OER: 228 mV/10 mA cm−2 in 1 M KOH. [ABSTRACT FROM AUTHOR]

Establishing efficient co-catalytic loaded semiconductors for efficient charge separation is a hopeful way for enhance photocatalytic water splitting hydrogen evolution. Herein, we successfully constructed the Cd 0.5 Zn 0.5 S/Ni 2 P (CZS/Ni 2 P) nanocomposites via two-step hydrothermal method. The CZS/Ni 2 P composites show much improved activity than the origin CZS for photocatalytic H 2 generation. When the content of Ni 2 P loaded on the Cd 0.5 Zn 0.5 S (CZS) is 0.3 mol%, the photocatalyst achieves the highest photocatalytic hydrogen generation rate of 41.26 mmol g−1 h−1 under visible light. The Ni–S bonds on the close contact interface between CZS and Ni 2 P can be act as electron-bridge to provide a channel for electron transfer. During the photocatalysis processing, Ni 2 P can be used as electron traps to attract electrons from CZS, resulting in the improvement of the photocatalytic performance. • A novel noble-metal-free CZS/Ni 2 P photocatalyst via two-step hydrothermal method. • The CZS/Ni 2 P photocatalyst boosts photocatalytic hydrogen evolution. • The Ni–S bonds can effectively promote the charge transfer and separation of CZS. • The effect of Ni 2 P amounts on photocatalytic performance was investigated. • The highest H2 evolution rate (41.26 mmol g−1 h−1) from the optimum composition. [ABSTRACT FROM AUTHOR]