Ultrathin Anatase TiO₂ Nanosheets for High‐Performance Photocatalytic Hydrogen Production

Abstract

An ethanol solvothermal route has been developed to prepare ultrathin anatase TiO nanosheets with dominant {001} facets (≈97%), a thickness of ≈2.5 nm, and a side length of ≈200 nm. The introduction of ethanol solvent significantly enhances the content of surface chemisorbed F on the TiO nanosheet, which has a higher stability and further lowers the surface energy of {001} facets, giving rise to the large percentage of active {001} facets. Adopting well-defined morphology, such nanosheets loaded with 1 wt% Pt exhibit an H evolution rate as high as 17.86 mmol h g , and the corresponding apparent quantum efficiency has been determined to be 34.2%.

Recent Advancements in the Understanding of the Surface Chemistry in TiO2 Photocatalysis

“…Cu-loaded anatase particles are a good photocatalyst for CO 2 photoreduction with formation of CO [49]. A theoretical model was suggested for the photocatalytic cycle on Cu-loaded (101) surface of anatase, in which CO 2 adsorption at the Cu 4 -TiO 2 interface is strong (∆H ads = −126 kJ/mol) with formation of carbonate.…”

Insights into the TiO2-Based Photocatalytic Systems and Their Mechanisms

“…In another study, the synthesis of TiO 2 solid and hollow nanocubes have been demonstrated, as shown in Figure 2, and applied for the photocatalytic-mediated synthesis of benzimidazole under UV and visible conditions [46]. Similarly, TiO 2 with different morphologies such as nanospheres, nanocubes, nanotubes, nanorods, nanoflowers, nanosheets, and nanofibers have been synthesized and studied for their photocatalytic applications [47][48][49][50][51][52][53]. The size and morphology control over TiO 2 photocatalyst exhibit significant influences over their (i) optical properties such as tunable band-gap energy, repositioning of band edge positions, visible light absorption, etc., (ii) electronic properties such as increased carrier lifetime, enhanced photocurrent conduction, reduced recombination, and (iii) surface properties such as enhanced surface energy, porous structures, enhanced surface adsorption, etc.…”

Self-organized and self-assembled TiO2 nanosheets and nanobowls on TiO2 nanocavities by electrochemical anodization and their properties

“…Due to their unusual physical, electrical and chemical properties and attractive applications in the field of the electrochemistry and electronics, nanosheets are being widely studied [1,2]. Nanosheets are nanostructured materials that have a shape of sheet whose thickness is lesser than 100 nm and their length is by the order of a few micrometers [2,3].…”

“…Due to their unusual physical, electrical and chemical properties and attractive applications in the field of the electrochemistry and electronics, nanosheets are being widely studied [1,2]. Nanosheets are nanostructured materials that have a shape of sheet whose thickness is lesser than 100 nm and their length is by the order of a few micrometers [2,3]. Commonly, nanosheets are synthesized either by exfoliation or hydrothermal and solvothermal processes [1][2][3][4][5][6][7] and they have been applied to Li-ion batteries and supercapacitors for improving the charge and discharge time, and in solar cells [1][2][3][4][5][6][7][8].…”

“…Nanosheets are nanostructured materials that have a shape of sheet whose thickness is lesser than 100 nm and their length is by the order of a few micrometers [2,3]. Commonly, nanosheets are synthesized either by exfoliation or hydrothermal and solvothermal processes [1][2][3][4][5][6][7] and they have been applied to Li-ion batteries and supercapacitors for improving the charge and discharge time, and in solar cells [1][2][3][4][5][6][7][8]. In 2019, Zhao et al investigated GeSe nanosheets, and demonstrated that these can be used in surface plasmon resonance sensor by depositing it by spin coating, improving the sensitivity of the sensor in the detection of heavy metals and chemical molecular identification [9].…”