Fabrication of an amorphous metal oxide/p-BiVO4 photocathode: understanding the role of entropy for reducing nitrate to ammonia. Issue 4 (24th January 2022)

• Record Type: Journal Article
• Authors: Wang, Fengfeng; Ding, Qijia; Bai, Yajie; Bai, Hongye; Wang, Song; Fan, Weiqiang
• Is Part Of: Inorganic chemistry frontiers. Volume 9:Issue 4(2022)
• Page Start: 805
• Page End: 813
• Publication Date: 2022-01-24
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d1qi01472b
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : Entropy regulation makes an amorphous metal oxide/p-BiVO4 heterostructure a desirable catalyst for the NO3 − reduction reaction in a photoelectrochemical system. Abstract : The controllable design of chemical microenvironment with the expected thermodynamics and kinetics for boosting catalytic activity and selectivity presents a challenge. Herein, an amorphous metal oxide (A-M x O y ) was employed to understand the polymetallic association of the effect of entropy, revealing the interplay between entropy and the NO3 − reduction reaction (NITRR) in a photoelectrochemical (PEC) system. Based on ultrafast transient absorption spectroscopy, the signal recovery of an optimal heterostructure (CoFeMnO/BiVO4 ) was 9.1 ps, confirming that amorphous CoFeMnO effectively promotes the kinetic factor of electrons. Thus, the NH3 yield rate of the optimal heterostructure (CoFeMnO/BiVO4 ) is up to 17.82 μg h −1 cm −2 (at −0.1 V vs. RHE), which is almost twice that of p-BiVO4 . Furthermore, isotope 1 H nuclear magnetic resonance spectroscopy was used to further demonstrate the exactitude of the NH3 evolutionary process, using 15 NO3 − as the N resource. Therefore, desirable entropy regulation and NH3 production make the herein A-M x O y /BiVO4 heterostructure a promising NITRR catalyst for use in a future solar conversion system.