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Electrocatalytic NO reduction reaction to generate NH 3 under ambient conditions offers an attractive alternative to the energy-extensive Haber-Bosch route; however, the challenge still lies in the development of cost-effective and high-performance electrocatalysts. Herein, nanoporous VN film is first designed as a highly selective and stable electrocatalyst for catalyzing reduction of NO to NH 3 with a maximal Faradaic efficiency of 85% and a peak yield rate of 1.05 × 10 -7 mol•cm -2 •s -1 (corresponding to 5,140.8 g•h -1 •mg cat.-1 ) at -0.6 V vs. reversible hydrogen electrode in acid medium. Meanwhile, this catalyst maintains an excellent activity with negligible current density and NH 3 yield rate decays over 40 h. Moreover, as a proof-of-concept of Zn-NO battery, it delivers a high power density of 2.0 mW•cm -2 and a large NH 3 yield rate of 0.22 × 10 -7 mol•cm -2 •s -1 (corresponding to 1,077.1 g•h -1 •mg cat.-1 ), both of which are comparable to the best-reported results. Theoretical analyses confirm that the VN surface favors the activation and hydrogenation of NO by suppressing the hydrogen evolution. This work highlights that the electrochemical NO reduction is an eco-friendly and energy-efficient strategy to produce NH 3 .

We report two ternary phase diagrams that show the synthesis conditions to prepare protein@ZIF biocomposites with different phases, including BSA@ZIF-C and insulin@ZIF-C. For each biocomposite, we measured distinct encapsulation efficiency and release profile properties.

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Strain regulation has become an important strategy to tune the surface chemistry and optimize the catalytic performance of nanocatalysts. Herein, the construction of atomic‐layer IrOx on IrCo nanodendrites with tunable IrO bond length by compressive strain effect for oxygen evolution reaction (OER) in acidic environment is demonstrated. Evidenced from in situ extended X‐ray absorption fine structure, it is shown that the compressive strain of the IrOx layer on the IrCo nanodendrites decreases gradually from 2.51% to the unstrained state with atomic layer growth (from ≈2 to ≈9 atomic layers of IrOx), resulting in the variation of the IrO bond length from shortened 1.94 Å to normal 1.99 Å. The ≈3 atomic‐layer IrOx on IrCo nanodendrites with an IrO bond length of 1.96 Å (1.51% strain) exhibits the optimal OER activity compared to the higher‐strained (2.51%, ≈2 atomic‐layer IrOx) and unstrained (>6 atomic‐layer IrOx) counterparts, with an overpotential of only 247 mV to achieve a current density of 10 mA cm−2. Density functional theory calculations reveal that the precisely tuned compressive strain effect balances the adsorbate–substrate interaction and facilitates the rate‐determining step to form HOO*, thus assuring the best performance of the three atomic‐layer IrOx for OER.

Synthetic fuels produced from CO 2 /H 2 O are an attractive alternative energy carrier. Here we demonstrate a novel strategy to electrochemically convert CO 2 /H 2 O into hydrocarbon in a single step in an oxygen-ion conducting solid oxide electrolyser. Methane was directly synthesized in an efficient electrolyser with configuration of (anode) (La 0.8 Sr 0.2 ) 0.95 MnO 3Àd /YSZ/La 0.2 Sr 0.8 TiO 3+d (cathode) by combining coelectrolysis of CO 2 /H 2 O and in situ Fischer-Tropsch-type synthesis. We demonstrate a high Faradaic yield of CO/H 2 and lower methane yield, which shows that the limit on conversion efficiency comes from the heterogeneous catalysis process. Electrochemical results also show that the electrochemical reduction of La 0.2 Sr 0.8 TiO 3+d cathode is the main process at low electrical voltages while the coelectrolysis is the main process at high voltages.

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