writer：Shuo Zhang, Liting Yan*, Huimin Jiang, Lingzhi Yang, Yanchao Zhao, Xue Yang, Yameng Wang, Jianxing S
keywords：foamed Ag3CuS2 films；self-supporting electrodes without substrate；ammonia electro-oxidation reaction；liquid ammonia electro-oxidation reaction；ammonia electrolysis
source：期刊
specific source：ACS APPLIED MATERIALS & INTERFACES，2022，14 (7) , pp.9036-9045
Issue time：2022年
Ammonia (NH3) is one of the hydrogen carriers that has received extensive attention due to its high hydrogen content and carbon-free nature. The ammonia electro-oxidation reaction (AOR) and the liquid AOR (LAOR) are integral parts of an ammonia-based energy system. The exploration of low-cost and efficient electrocatalysts for the AOR and LAOR is very important but very difficult. In this work, a novel self-supporting AOR and LAOR bifunctional electrocatalyst of a Ag3CuS2 film is synthesized by a simple hydrothermal method. The Ag3CuS2 film without a substrate shows efficient catalytic activity and enhanced stability for NH3 electrolysis in both aqueous ammonia solution and liquid ammonia, including an onset potential of 0.7 V for the AOR and an onset potential of 0.4 V for the LAOR. The density functional theory calculations prove that compared to Cu atoms, Ag atoms with appropriate charge density on the surface of Ag3CuS2 are more electrocatalytically active for NH3 splitting, including the low energy barrier in the rate-determining *NH3 dehydrogenation step and the spontaneous tendency in the N-2 desorption process. Overall, the foamed Ag3CuS2 film is one of prospective low-cost and stable electrocatalysts for the AOR and LAOR, and the self-supporting strategy without a substrate provides more perspectives to tailor more meaningful and powerful electrocatalysts.