Au nanoclusters anchored on TiO2 nanosheets for high-efficiency electroreduction of nitrate to ammonia

• Published in: Nano research 2024-03, Vol.17 (3), p.1209-1216
• Main Authors: Yang, Miaosen, Wei, Tianran, He, Jia, Liu, Qian, Feng, Ligang, Li, Hongyi, Luo, Jun, Liu, Xijun
• Format: Article
• Language: English
• Subjects: Ammonia; Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Catalysts; Chemical reduction; Chemistry and Materials Science; Condensed Matter Physics; Efficiency; Materials Science; Metal clusters; Nanoclusters; Nanosheets; Nanotechnology; Nitrate reduction; Nitrate removal; Nitrates; Noble metals; Nutrient removal; Research Article; Titanium dioxide; Transition metals
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-023-5997-z

Electrocatalytic nitrate reduction reaction (NO 3 RR) offers a unique rationale for green NH 3 synthesis, yet the lack of high-efficiency NO 3 RR catalysts remains a great challenge. In this work, we show that Au nanoclusters anchored on TiO 2 nanosheets can efficiently catalyze the conversion of NO 3 RR-to-NH 3 under ambient conditions, achieving a maximal Faradic efficiency of 91%, a peak yield rate of 1923 µg·h −1 ·mg cat. −1 , and high durability over 10 consecutive cycles, all of which are comparable to the recently reported metrics (including transition metal and noble metal-based catalysts) and exceed those of pristine TiO 2 . Moreover, a galvanic Zn-nitrate battery using the catalyst as the cathode was proposed, which shows a power density of 3.62 mW·cm −2 and a yield rate of 452 µg·h −1 ·mg cat. −1 . Theoretical simulations further indicate that the atomically dispersed Au clusters can promote the adsorption and activation of NO 3 − species, and reduce the NO 3 RR-to-NH 3 barrier, thus leading to an accelerated cathodic reaction. This work highlights the importance of metal clusters for the NH 3 electrosynthesis and nitrate removal.