Controllable growth of WO3@GDY heterointerface for efficient NH3 synthesis

Abstract

Heterogeneous electrocatalytic nitrate reduction reaction (NtRR) provides a promising technology for ammonia (NH₃) synthesis at room temperatures and ambient pressures and has been regarded as an alternative to the traditional Haber–Bosch process. However, the selective conversion of NO₃⁻ to NH₃ is still challenged by the lack of efficient catalysts due to the sluggish charge transfer kinetics and poor selectivity. Herein, we report the selective and active conversion of nitrate to ammonia on WO₃@GDY heterostructured catalysts with high faradaic efficiency (FE) of 85.6% and NH₃ yield rate of 2582.6 μg h⁻¹ cm⁻² in 0.1 M HCl electrolyte containing 0.1 M NO₃⁻ and an excellent long-term stability. Experimental results illustrated the incomplete charge transfer between GDY and W atoms and the mixed valence of W induced by GDY leading to the formation of more active sites and the enhancement in charge transfer ability, which, therefore caused improvements in the overall catalytic activity.