Mixed 3D/2D dimensional TiO₂ nanoflowers/MoSe₂ nanosheets for enhanced photoelectrochemical hydrogen generation

Abstract

Recently, various kinds of methods have been implemented to broaden the visible light response and fasten the carrier's separation of TiO2‐based photoanodes. As a promising hydrogen evolution reaction catalyst, MoSe2 is rarely investigated especially combined with TiO2 photoanode. In this study, we report a composite photoanode of MoSe2 nanosheets (with 1T and 2H phase)‐modified 3D TiO2 nanoflowers (NFs).The hybrid of 3D TiO2 NFs/2D MoSe2 holds great promise in boosting the PEC water splitting performance. TiO2 NFs/MoSe2‐15 showed the largest photocurrent density of 1.40 mA/cm2, which was five times higher than that of pure TiO2 NFs under AM1.5G illumination. Moreover 10 times improvement in current density was observed for the TiO2 NFs/MoSe2‐15 under visible light. This increase could be ascribed to synergistic effects of light absorption enhancement and more efficient carrier separation after MoSe2 modification. This study not only provides a reference to boost the photoelectrochemical performance of photoelectrodes but also renders a perspective on the potential applications of MoSe2 nanosheets.

Electrostatic self‐assembly of 2D‐2D CoP/ZnIn2S4 nanosheets for efficient photocatalytic hydrogen evolution

“…The intimate sheet-on-sheet contact between ZIS and CoP will contribute to electron transfer from ZIS to CoP, thus inhibiting the photogenerated electron-hole pairs from recombining in ZIS. 33 The closeknit coupling between CoP and ZIS is further testified by the HRTEM image ( Figure 3C). The lattice spacing of 0.28 nm is assigned to the (011) of CoP, 31 whereas the lattice spacing of 0.32 nm with higher contrast and longer range of lattice fringe is ascribed to the (102) plane of ZIS, 29 further testifying ZIS and CoP are co-exist.…”

“…A careful inspection of the TEM image finds that CoP nanosheets have been loaded on the ZIS nanosheets tightly (Figure 3B). The intimate sheet‐on‐sheet contact between ZIS and CoP will contribute to electron transfer from ZIS to CoP, thus inhibiting the photogenerated electron‐hole pairs from recombining in ZIS 33 . The close‐knit coupling between CoP and ZIS is further testified by the HRTEM image (Figure 3C).…”

Nanoscale metal oxides–2D materials heterostructures for photoelectrochemical water splitting—a review

“…Combining the two, Li et al showed a heterostructure with smaller E g of 2.77 eV compared to the bare TiO 2 of 2.94 eV. 77 They also found that the optimum dipping concentration of MoSe 2 is 6 mM, which produced a heterostructure with the lowest photoluminescence signal (Fig. 11b), indicating a low charge recombination rate due to the fast photogenerated electron-hole pairs separation across the heterojunction.…”

“…Over the past decades, numerous binary MOs have been studied extensively for PEC water splitting. These include ZnO, 70,71 α-Fe 2 O 3 , 72,73 Cu 2 O, 74,75 TiO 2 , 76,77 SnO 2 , 78,79 MoO 3 , 71,80 WO 3 , 81,82 and V 2 O 5 . 83,84 Besides that, ternary MOs of, for example, BiVO 4 , 21,85 Bi 2 MoO 6 , 80,86 Bi 2 WO 6 , 87,88 CuWO 4 , 22,89 and ZnFe 2 O 4 , 90,91 have also emerged as viable options.…”

Co‐doping of P(V) and Ti(III) in leaf‐architectured TiO2 for enhanced visible light harvesting and solar photocatalysis

“…Extending the absorption spectrum of TiO 2 to include more visible light, which takes ~45% of the total solar energy, has been of immense interest. 3,4 Hetero-element doping has long been demonstrated for improved visible light utilization. Dopants including metals or nonmetals (anion or cation), in the form of substitutional or interstitial, have been extensively studied.…”