Electrocatalytic Reduction of NO3- to Ultrapure Ammonia on {200} Facet Dominant Cu Nanodendrites with High Conversion Faradaic Efficiency

Shivaraj B Patil; Ting-Ran Liu; Hung-Lung Chou; Yu-Bin Huang; Chia-Che Chang; Yi-Chia Chen; Ying-Sheng Lin; Hsin Li; Yi-Cheng Lee; Yuan Jay Chang; Ying-Huang Lai; Cheng-Yen Wen; Di-Yan Wang

doi:10.1021/acs.jpclett.1c02236

Electrocatalytic Reduction of NO₃^- to Ultrapure Ammonia on {200} Facet Dominant Cu Nanodendrites with High Conversion Faradaic Efficiency

J Phys Chem Lett. 2021 Aug 26;12(33):8121-8128. doi: 10.1021/acs.jpclett.1c02236. Epub 2021 Aug 19.

Authors

Affiliations

¹ Department of Chemistry, Tunghai University, Taichung 40704, Taiwan.
² Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
³ Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan.

PMID: 34410136
DOI: 10.1021/acs.jpclett.1c02236

Abstract

Nitrate (NO₃^-) reduction reaction (NtRR) is considered as a green alternative method for the conventional method of NH₃ synthesis (Haber-Bosch process), which is known as a high energy consuming and large CO₂ emitting process. Herein, the copper nanodendrites (Cu NDs) grown along with the {200} facet as an efficient NtRR catalyst have been successfully fabricated and investigated. It exhibited high Faradaic efficiency of 97% at low potential (-0.3 V vs RHE). Furthermore, the ¹⁵NO₃^- isotope labeling method was utilized to confirm the formation of NH₃. Both experimental and theoretical studies showed that NtRR on the Cu metal nanostructure is a facet dependent process. Dissociation of NO bonding is supposed to be the rate-determining step as NtRR is a spontaneously reductive and protonation process for all the different facets of Cu. Density functional theory (DFT) calculations revealed that Cu{200} and Cu{220} offer lower activation energy for dissociation of NO compared to that of Cu{111}.