Shinagawa Tatsuya, Ng Marcus Tze-Kiat, Takanabe Kazuhiro
King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center and Physical Sciences and Engineering Division, 4700 KAUST, Thuwal, 23955-6900, Saudi Arabia.
Present address: Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich, Vladmir-Prelog-Weg 1, CH-8093, Zurich, Switzerland.
ChemSusChem. 2017 Nov 9;10(21):4155-4162. doi: 10.1002/cssc.201701266. Epub 2017 Sep 21.
The development of processes for the conversion of H O and CO driven by electricity generated by renewable means is essential to achieving sustainable energy and chemical cycles, in which the electrocatalytic oxygen evolution reaction (OER) is one of the bottlenecks. In this study, the influences of the electrolyte molarity and identity on the OER at alkaline to neutral pH were investigated at an appreciable current density of around 10 mA cm , revealing both the clear boundary of reactant switching between H O/OH , owing to the diffusion limitation of OH , and the substantial contribution of the mass transport of the buffered species in buffered mild-pH conditions. These findings suggest a strategy of electrolyte engineering: tuning the electrolyte properties to maximize the mass-transport flux. The concept is successfully demonstrated for the OER, as well as overall water electrolysis in buffered mild-pH conditions, shedding light on the development of practical solar fuel production systems.
开发由可再生能源发电驱动的将水和二氧化碳转化的工艺对于实现可持续能源和化学循环至关重要，其中电催化析氧反应（OER）是瓶颈之一。在本研究中，在约10 mA cm的可观电流密度下，研究了碱性至中性pH条件下电解质摩尔浓度和种类对OER的影响，揭示了由于OH的扩散限制，H2O/OH之间反应物转换的清晰界限，以及在缓冲的温和pH条件下缓冲物种传质的重要贡献。这些发现提出了一种电解质工程策略：调整电解质性质以最大化传质通量。该概念已成功应用于OER以及缓冲温和pH条件下的整体水电解，为实用太阳能燃料生产系统的开发提供了启示。
