Rare-earth metal based Pr/Pr2(SeO3)3 Mott-Schottky heterojunction for electrocatalytic water splitting to produce hydrogen linking to organics oxidation

Abstract

Hydrogen is a new free carbon emission energy form to solve the energy crisis all over the world. To obtain hydrogen, oxygen evolution reaction (OER) in the electrocatalytic water splitting has little value so it can be replaced by organics oxidation reactions, but how to fabricate the electrocatalyst is the key point. Herein, the rare-earth metal Pr and chalcogen element Se are used to construct the Pr/Pr2(SeO3)3 Mott-Schottky heterojunction, which is used as an electrocatalyst for water splitting. Amongst them, the Pr/Pr2(SeO3)3-1 heterojunction shows the superior electrocatalytic performances that the glucose oxidative reaction (GOR) overpotential is 291 mV at 10 mA cm−2 in 1 M KOH + 0.1 M glucose, and the hydrogen evolution reaction (HER) overpotential is 145 mV at 10 mA cm−2 in 1 M KOH. For the GOR process, the glucose is electrocatalytic oxidized to high-value-added gluconic acid, and the splitting voltage of Pr/Pr2(SeO3)3–1 is only 1.51 V at 10 mA cm−2, and hydrogen is also produced under the effect of “one stone two birds”.