Visible-Light-Driven Photocatalytic Dehydrogenation of Alcohols on TiO₂ via Ligand-to-Metal Charge Transfer for Coproduction of H₂ and Aldehydes

Abstract

Developing visible-light-driven photocatalysts for the catalytic dehydrogenation of organics is of great significance for sustainable solar energy utilization. Here, we first report that aromatic alcohols could be efficiently split into H 2 and aldehydes over TiO 2 under visible-light irradiation through a ligand-to-metal charge transfer (LMCT) mechanism. A series of TiO 2 catalysts with different surface contents of the hydroxyl group (−OH) have been synthesized by controlling the hydrothermal and calcination synthesis methods. An optimal H 2 production rate of 18.6 μmol h −1 is obtained on TiO 2 synthesized from the hydrothermal method with a high content of surface −OH. Experimental characterizations and comparison studies reveal that the surface −OH markedly influences the formation of LMCT complexes and thus changes the visible-light-driven photocatalytic performance. This work is anticipated to inspire further research endeavors in the design and fabrication of visible-light-driven photocatalyst systems based on the LMCT mechanism to realize the simultaneous synthesis of clean fuel and fine chemicals.

Facile Surface Engineering of TiO2 Nanosheets for Enhanced Isopropanol Sensing under UV Irradiation

“…Among them, the peaks at 2970, 2931, and 2880 cm –1 were assigned to the stretching vibrations of C–H bonds (ν C–H ), and the peaks at 1465 and 1380 cm –1 were attributed to the symmetric and asymmetric stretch modes of methyl (δ CH3 ), while the band at 1165 cm –1 was ascribed to the stretching vibrations of C–C bonds (ν C–C ) . Besides, based on literatures reported, there are two primary modes of IPA adsorption on TiO 2 . , One is dissociative adsorption, where the O–H group of IPA is broken to form a −C–O–Ti– bond and the H atom transfers to the adjacent O b atoms to create a new hydroxyl group on the surface. In this mode, there are representative bands at 1135 and 3654 cm –1 , which are assigned to the stretching vibrations of C–O bonds (ν C–O ) and the stretch of hydroxyl groups (ν OH ).…”

Highly Efficient and Reusable PI/TiO2 Organic–Inorganic Microfibers for Sustainable Photocatalytic Degradation of Multiple Organic Pollutants under Simulated Sunlight

“…With the constant changes in modern society, there has been a pervasive emphasis on utilizing harnessing-efficient, cost-effective, user-friendly, and environmentally friendly photocatalytic technology to effectively combat environmental pollution . Therefore, numerous inorganic semiconductor photocatalysts, including metal oxides such as TiO 2 , ZnO, and CuO; nitrides like GaN and g-C 3 N 4 ; and sulfides such as MoS 2 and Cu 2 S have been employed in the field of photocatalysis. Among these photocatalysts, n-type TiO 2 has stimulated tremendous research interests because of its unique physicochemical properties, such as high catalytic activity, strong oxidization capability, suitable electronic and optical properties, excellent chemical and thermal stability, high photoactivity, and the availability of immobilization on various substrates .…”