Zirconium trisulfide ultrathin nanosheets as efficient catalysts for water oxidation in both alkaline and neutral solutions

Abstract

Developing highly efficient electrocatalysts for oxygen evolution reaction (OER) has emerged as one of the most important research hot spots in energy-related fields due to its critical role in coupling with hydrogen evolution reaction to enhance the total efficiency of water splitting. However, the well-established catalysts for water oxidation up to now are mainly effective in strongly alkaline solutions, thus hindering the practical application in total water splitting. Under this circumstance, herein, we put forward a novel oxygen-evolving electrocatalyst based on zirconium trisulfide (ZrS₃) ultrathin nanosheets for the first time, achieving efficient water oxidation behavior in both alkaline and neutral solutions. With the merits of the abundant disulfide bonds on the surface of the ZrS₃ ultrathin nanosheets, the OER performance exhibits great enhancement against the bulk material. An ultralow onset overpotential of 244 mV and a small Tafel slope of 45 mV decade⁻¹ are achieved for the ZrS₃ ultrathin nanosheets in strongly alkaline solution (pH = 14), while superior OER activity with low onset overpotential and small Tafel slope is also realized in weakly alkaline solutions and even under neutral conditions (pH = 6.9), suggesting the excellent water oxidation performance and showing broad applicable potential for total water splitting. The exploration of this novel catalyst will not only pave a new pathway in searching for advanced catalysts with high efficiency, but also offer an effective strategy in designing functional structures for other electrocatalysts.