Synthesis of yttrium and cerium doped ZnO nanoparticles as highly inexpensive and stable photocatalysts for hydrogen evolution

Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) techniques. The introduction of yttrium ions has efficiently increased the relative percentage of Ce³⁺ ions in ZnO. Yttrium and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution (10.61 mmol/((g·h)) higher than previously reported optimal value for rare earth co-doped ZnO photocatalysts. This remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y³⁺/Y²⁺ and Ce⁴⁺/Ce³⁺ redox couples. This report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring effect. The hydrogen evolution was also tested using Na₂S and Na₂SO₃ as electron donors under visible light illumination. The synthesized photocatalysts also exhibit high stability.