Bifunctional catalyst based on molecular structure: Spherical mesoporous TiO2 and gCN for photocatalysis

Abstract

Here, we designed a molecular structure fabrication route based on spherical mesoporous TiO2 and exfoliated graphitic carbon nitride (mTiO2_ex-gCN) by combining hard templating and hydrothermal methods. The mTiO2_ex-gCN boosted two photocatalytic processes: hydrogen evolution under simulated solar illumination and degradation of Rhodamine B (RhB) with the assistance of UV–vis and visible light irradiations. RhB degradation under UV–vis light was 2.94 and 1.39 times higher than ex-gCN and mTiO2, respectively. Additionally, dye degradation under visible light was enhanced by a 1.22 factor in respect to ex-gCN. However, a more spectacular performance was detected in the process of photocatalytic hydrogen evolution – the efficiency of the catalyst yielded a 70 times higher amount of H2 in respect to ex-gCN. It is proposed that enhanced photocatalytic activity is due to synergy provided by individual counterparts, which tuned energy band gap, improved specific surface area, and enhanced ability to suppress the charge carrier recombination.