Graphitic Carbon Nitride (g-C3N4) Modified N-Doped LaTiO3 As an Organic–Inorganic Hybrid for Higher Visible Light Photocatalytic and Photo-Electrochemical Performance

Abstract

Photocatalysis mimics natural photosynthesis by converting solar energy into chemical energy, and hence, it has tremendous potential to be an alternative sustainable means for dealing with global energy crisis and environmental remediation. LaTiO3 is an important rare-earth-metal-based perovskite semiconductor, but unfortunately, the visible light photocatalytic and photocurrent activity of LaTiO3 has been rarely studied. In the present work, we report interesting results on enhancing visible light photocatalytic and photocurrent activity of LaTiO3 via N-doping and making heterojunction with metal free g-C3N4. We synthesized the g-C3N4 modified N-doped LaTiO3 (CLT) organic-inorganic hybrid via a sol-gel polymerized complex method followed by facile solid state transformation route. The synthesized hybrids are thoroughly characterized. The CLT hybrid exhibits not only longer wavelength absorption in the visible region but also an enhancement in the catalytic activity under visible light compared to pure N-doped LaTiO3 and g-C3N4. The improved visible light activity of the CLT hybrid is ascribed by its suitable band edge potential and better separation of photoinduced charge carriers through the heterojunction of g-C3N4 and N-LaTiO3. Based on the results of photoluminescence, electrochemical impedance, and radical scavenger studies, a possible photocatalytic mechanism for the hybrid is also proposed. The photostable and reusable CLT hetero-structure is expected to provide new insight for the application of organic-inorganic hybrid and perovskite in light energy conversion and could be suitable for water splitting under sun light as well. Reference: 1. Appl. Surf. Sci. 2018, 452, 400-412 2. Angew. Chem. Int. Ed. 2017, 56, 2064–2068.