Abstract
The development of processes for the conversion of H2O/CO2 driven by electricity generated in renewable manners is essential to achieve sustainable energy and chemical cycles, in which the electrocatalytic oxygen evolution reaction (OER) is one of the bottlenecks. In this contribution, the influences of the electrolyte molarity and identity on OER at alkaline to neutral pH were investigated at an appreciable current density of ~10 mA cm-2, revealing (1) the clear boundary of reactant switching between H2O/OH- due to the diffusion limitation of OH- and (2) the substantial contribution of the mass transport of the buffered species in buffered mild pH conditions. These findings propose a strategy of electrolyte engineering: tuning the electrolyte properties to maximize the mass-transport flux. The concept was successfully demonstrated for OER as well as overall water electrolysis in buffered mild pH conditions, shedding light on the development of practical solar fuel production systems.
Original language | English (US) |
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Pages (from-to) | 4155-4162 |
Number of pages | 8 |
Journal | ChemSusChem |
Volume | 10 |
Issue number | 21 |
DOIs | |
State | Published - Sep 21 2017 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: The research reported in this publication was supported by King Abdullah University of Science and Technology (KAUST). Dr. Ahmed Ziani and Liga Stegenburga are acknowledged for the preparation of the CoOx RDE, and the NiMo/NF and Co/NF electrodes, respectively. The authors appreciate the kind assistance of Prof. Nikos Hadjichristidis and Keisuke Obata for the viscosity measurements.