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Atmospheric nitrogen fixation using a photocatalytic system is a promising approach to produce ammonia. However, most of the recently explored photocatalysts for N 2 fixation are in the powder form, suffering from agglomeration and difficulty in the collection and leading to unsatisfactory conversion efficiency. Developing efficient film catalysts for N 2 photofixation under ambient conditions remains challenging. Herein, we report the efficient photofixation of N 2 over a periodic WS 2 @TiO 2 nanoporous film, which is fabricated through a facile method that combines anodization, E-beam evaporation, and chemical vapor deposition (CVD). Oxygen vacancies are introduced into TiO 2 nanoporous films through Ar annealing treatment, which plays a vital role in N 2 adsorption and activation. The periodic WS 2 @TiO 2 nanoporous film with an optimized WS 2 content shows highly efficient photocatalytic performance for N 2 fixation with an NH 3 evolution rate of 1.39 mmol g −1 h −1 , representing one of the state-of-the-art catalysts. 

Abstract Electrode stabilization by surface passivation has been explored as the most crucial step to develop long‐cycle lithium‐ion batteries (LIBs). In this work, functionally graded materials consisting of “conversion‐type” iron‐doped nickel oxyfluoride (NiFeOF) cathode covered with a homologous passivation layer (HPL) are rationally designed for long‐cycle LIBs. The compact and fluorine‐rich HPL plays dual roles in suppressing the volume change of NiFeOF porous cathode and minimizing the dissolution of transition metals during LIBs cycling by forming a structure/composition gradient. The structure and composition of HPL reconstructs during lithiation/delithiation, buffering the volume change and trapping the dissolved transition metals. As a result, a high capacity of 175 mAh g⁻¹(equal to an outstanding volumetric capacity of 936 Ah L⁻¹) with a greatly reduced capacity decay rate of 0.012% per cycle for 1000 cycles is achieved, which is superior to the NiFeOF porous film without HPL and commercially available NiF₂‐FeF₃powders. The proposed chemical and structure reconstruction mechanism of HPL opens a new avenue for the novel materials development for long‐cycle LIBs.