Molecular Crowding Effect in Aqueous Electrolytes to Suppress Hydrogen Reduction Reaction and Enhance Electrochemical Nitrogen Reduction
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review
Author(s)
Related Research Unit(s)
Detail(s)
Original language | English |
---|---|
Article number | 2101699 |
Journal / Publication | Advanced Energy Materials |
Volume | 11 |
Issue number | 36 |
Online published | 6 Aug 2021 |
Publication status | Published - 23 Sept 2021 |
Link(s)
Abstract
The H2 evolution reaction (HER), one of the most intractable issues for the electrochemical N2 reduction reaction (NRR), seriously hinders NH3 production selectivity and yield rate. Considering that hydrogenation reactions are essential to the aqueous NRR process, acidic electrolytes would be an optimum choice for NRR as long as the proton content and the HER kinetics can be well balanced. However, there is a striking lack of strategies available for electrolyte optimization, i.e., rationally regulating electrolytes to suppress HER and promote NRR, to achieve impressive NRR activity. Herein, a HER-suppressing electrolytes are developed using hydrophilic poly(ethylene glycol) (PEG) as the electrolyte additive by taking advantage of its molecular crowding effect, which promotes the NRR by retarding HER kinetics. On a TiO2 nanoarray electrode, a significantly improved NRR activity with NH3 Faraday efficiency (FE) of 32.13% and yield of 1.07 µmol·cm−2·h−1 is achieved in the PEG-containing acidic electrolytes, 9.4-times and 3.5-times higher than those delivered in the pure acidic electrolytes. Similar enhancements are achieved with Pd/C and Ru/C catalysts, as well as in an alkaline electrolyte, demonstrating a universally positive effect of molecular crowding in the NRR. This work casts new light on aqueous electrolyte design in retarding HER kinetics and expediting the NRR.
Research Area(s)
- electrochemical HER, electrochemical N 2 reduction, kinetics suppression, molecular crowding effect, NH 3 production selectivity
Citation Format(s)
Molecular Crowding Effect in Aqueous Electrolytes to Suppress Hydrogen Reduction Reaction and Enhance Electrochemical Nitrogen Reduction. / Guo, Ying; Gu, Jinxing; Zhang, Rong et al.
In: Advanced Energy Materials, Vol. 11, No. 36, 2101699, 23.09.2021.
In: Advanced Energy Materials, Vol. 11, No. 36, 2101699, 23.09.2021.
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review