Platinum group nanoparticles doped BCN matrix: Efficient catalysts for the electrocatalytic reduction of nitrate to ammonia

• Published in: Journal of colloid and interface science 2024-06, Vol.664, p.84-95
• Main Authors: Wang, Zhengxi, Xia, Shiying, Deng, Xuefan, Baryshnikov, Glib, Kuklin, Artem, Ågren, Hans, Zhang, Haibo
• Format: Article
• Language: English
• Subjects: Ammonia; BCN matrix; catalytic activity; density functional theory; Electrocatalysis; electrodes; nanoparticles; Nitrate reduction; nitrates; nitrogen; platinum; Platinum -group nanoparticles; surface area
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2024.02.211

This article demonstrates boron carbon nitrogen compound supported platinum group (Pd/BCN, Pt/BCN and Ru/BCN) for electrocatalytic reduction of nitrate to ammonia. [Display omitted] •Highly efficient electrocatalytic NO3– reduction was realized by doped Pd,Ru,Pt/BCN.•Pd/BCN provided higher NH4+ production rate and Faraday efficiency.•DFT revealed the molecular mechanism of Pd/BCN in the nitrate reduction process. The effective treatment of nitrate (NO3−) in water as a nitrogen source and electrocatalytic NO3− reduction to ammonia (NH3) (NRA) have become preferred methods for NO3−-to-NH3 conversion. Achieving efficient NO3−-to-NH3 conversion requires the design and development of electrode materials with high activity and efficiency for the electrocatalytic NRA reaction. Herein, based on the special properties of dodecahydro-closo-dodecaborate anions, a BCN matrix, loaded with platinum-group nanoparticles (namely, Pd/BCN, Pt/BCN, and Ru/BCN), was prepared using a simple method for the electrocatalytic NRA reaction. Results showed that Pd/BCN exerts the best catalytic effect on the NRA reaction. The NH3 production rate reached 12.71 mg h−1 mgcat.−1 at −1.0 V vs. RHE. Faraday efficiency reached 91.79 %, which can be attributed to the more uniform distribution of the nanoparticles. Furthermore, Pd/BCN exhibited high cycling stability and resistance to ionic interference. Moreover, the density functional theory calculations indicated that small and well-distributed Pd nanoclusters in the BCN matrix have a large active surface area and promote the catalytic process. This study provides a new strategy to design catalysts for green ammonia synthesis.