Few-layered metallic 1T-MoS₂/TiO₂ with exposed (001) facets: two-dimensional nanocomposites for enhanced photocatalytic activities

Abstract

Titanium dioxide (TiO) with exposed (001) facets (TiO(001)) has attractive photocatalytic properties. However, the high recombination rate of the photo-excited charge carriers on this surface often limits its application. Here, we report that a few-layered 1T-MoS coating on TiO(001) nanosheets (abbreviated as MST) can be a promising candidate that overcomes some of the challenges of TiO(001). Computational and experimental results demonstrate that MST as a photocatalyst exhibits a significantly low-charge recombination rate as well as excellent long-term durability. The synthesized MST 2D nanocomposites show a 31.9% increase in photocatalytic activity for hydrogen (H) production relative to the counterpart TiO(001). MST offers a new route for further improvement of the photocatalytic activity of TiO with exposed high energy facets.

Hierarchical MoS2@TiO2 Heterojunctions for Enhanced Photocatalytic Performance and Electrocatalytic Hydrogen Evolution

“…This furtherc onfirms that the intimateM oS 2 @TiO 2 heterojunctions can significantly enhance the photocatalytic activity.T he slower decay time implies that photogenerated electrons in the MoS 2 @TiO 2 nanocomposite can have much longerc arrierl ifetimet han in MoS 2 . [34] Therefore, MoS 2 @TiO 2 has better photocatalytic performance than MoS 2 and TiO 2 .M oreover,t he electron transfer between MoS 2 andT iO 2 was investigated by using photoluminescences pectroscopy (PL;F igureS10). Normally,t he PL signals of semiconductor materials result from the recombination of photoinduced chargec arriers.…”

Compositing Two-Dimensional Materials with TiO2 for Photocatalysis

“…In another research, 1T-MoS 2 coated onto TiO 2 (001) composite (MST) was synthesized. DFT calculations suggested a closer distance between the interface electrons and MoS 2 surface than that of TiO 2 [131] (Figure 19). Therefore the photo-induced electrons can easily transfer to the conducting channel of MoS 2 .…”

“…As for 2H phase, the active site with catalytic activity is located at the edge of the MoS 2 layers and the basal surface of MoS 2 is catalytically inactive [134]. Therefore, the 1T phase of MoS 2 with active sites on both edge and basal planes attracts researchers' attention in recent years [118,125,131]. A typical schematic of MoS 2 /TiO 2 composites for photocatalytic hydrogen production is shown in Figure 18.…”

“…(a) The charge density difference, (b) electrostatic potential and differential charge density of the MoS 2 /TiO 2 (001) junction; (c) Planar-averaged differential electron density Dr(z) for MoS 2 /TiO 2 (001); (d) Photocatalytic mechanism for 1T-MoS 2 /TiO 2 . Reprinted with permission from [131]. Copyright 2017, the Owner Societies.…”

“…Other structures such as nanobelts and nanotubes have also been developed [129,130]. In addition to the morphology, the formation of a specific crystal structure of TiO2 as a substrate has also got attention to prepare high performance MoS2/TiO2 composites [130,131]. He et al [130] Reprinted with permission from [126].…”