Synergistic effects of multi-ions in metal oxides to boost up water splitting

The development of new highly effective catalysts for electrochemical energy conversion is a major challenge in tackling climate change. Water splitting for hydrogen production is an environmentally friendly process that provides a renewable, clean, and sustainable energy resource, but particularly the slow process of oxygen evolution reaction (OER) limits overall efficiency. Metal oxide catalysts are emerging as a good candidate for improving OER due to the advantages such as excellent performance, cost effectivity, and versatile coordination. However, when two or more various metal elements are mixed in a metal oxide, their synergetic effects on OER are not well studied on an atomic level. Here, we explore various methods to dramatically improve sluggish OER through synergistic studies of DFT calculations, electrochemical measurements, and in situ X-ray spectroscopy. By examining the atomic-level interactions between two or more metal elements with different properties, we will discuss various methods to reduce the problematic barrier of the rate-limiting step and maximize the reaction rate in OER.