Boosting nitrate electrosynthesis controlled by top-bridge mixed adsorption of 2*NOH over in-situ amorphous PdS2 nanoclusters

Amorphous nanomaterials with only short-range order at the atomic scale serve as the promising photo-/electrocatalysts widely used in water splitting for hydrogen production and electrochemical nitrogen fixation. Herein, amorphous PdS 2 nanoclusters (a-PdS 2 NCs) are homogeneously anchored on the surface of 1D poly(1-vinyl-3-ethylimidazolium bromide) functionalized polypyrrole nanotubes (PVEIB/PPyNTs) by the in situ induced growth. Taking N 2 as the N source, the obtained a-PdS 2 NCs@PVEIB/PPyNTs exhibit excellent electrocatalytic nitrogen oxidation reaction (NOR) performance, with the highest NO 3 − yield (56.59 μg h −1 mg −1 act. ) and Faradic efficiency (4.79 %) at 2.05 V (vs. RHE). Remarkable stability and selectivity for NOR are demonstrated by the consistent NO 3 − yield and Faradaic efficiency over six cycles, with no detectable NO 2 − . Theoretical calculations indicate that for PdS 2 with a unique amorphous structure, the lower energy barrier can be obtained by the mixed adsorption mode (one at top site, and the other at bridge site) in the step for the break of *HONNOH to 2*NOH, favoring the NOR process. This work is expected to stimulate further research and provide valuable insights into the application of amorphous nanomaterials in nitrate electrosynthesis. • Novel amorphous PdS 2 nanoclusters were induced to grow and anchored on PVEIB/PPyNTs. • The obtained a-PdS 2 NCs@PVEIB/PPyNTs exhibited the excellent NOR electroactivity. • The remarkable stability and selectivity towards NOR were achieved. • The top-bridge mixed adsorption of 2*NOH dominated the NOR process.