A Z-scheme photocatalyst constructed with an yttrium–tantalum oxynitride and a binuclear Ru(ii) complex for visible-light CO2 reduction

Abstract

An yttrium–tantalum oxynitride having a band gap of 2.1 eV (absorbing visible light at <580 nm) was applicable as a semiconductor component of a Z-scheme CO₂ reduction system operable under visible light, in combination with a binuclear Ru(II) complex that has strong absorption in the visible region (<600 nm). Excitation of this system with visible light under a CO₂ atmosphere induced photocatalytic formation of formic acid with very high selectivity (>99%).