Monolayer Attachment of Metallic MoS₂ on Restacked Titania Nanosheets for Efficient Photocatalytic Hydrogen Generation

Abstract

Monolayer attachment of metallic MoS 2 (1T) on restacked titania (Ti 0.87 O 2 0.52− ) nanosheets was attained via a facile two-step flocculation process of their colloidal suspensions with the aid of the difference in critical H + concentrations required for inducing flocculation of the respective nanosheets. The process produced porous flaky aggregates of restacked Ti 0.87 O 2 0.52− nanosheets covered with monolayer MoS 2 , which serves as the electron collector and provides abundant catalytically active sites for proton reduction reaction. The MoS 2 -modified restacked Ti 0.87 O 2 0.52− nanosheets showed a remarkably high photocatalytic efficiency for hydrogen generation (1.2 mmol h −1 g −1 ), being superior to those of the restacked Ti 0.87 O 2 0.52− nanosheets and P25-TiO 2 nanoparticles conventionally modified with MoS 2 (0.38, and 0.4 mmol h −1 g −1 , respectively). The extensive molecular-level interfacial coupling of Ti 0.87 O 2 0.52− /MoS 2 nanosheets facilitates efficient charge separation and fast electron transfer, resulting in the significantly enhanced photocatalytic activity.

Edge Rich Ultrathin Layered MoS2 Nanostructures for Superior Visible Light Photocatalytic Activity

“…Thus, the decreased lifetime of the MoS 2 nanoflowers infers that unsaturated S-edges could act as an electron trap and improve electron−hole separation. 52 X-ray photoelectron spectroscopy (XPS) measurement is conducted to study the chemical composition and phase state of the as-synthesized MoS 2 nanostructure. In the case of the MoS 2 nanoflowers sample, three noticeable peaks identified at 227.469, 228.963, and 232.183 eV (shown in Figure 2a) specify the S 2s, Mo 4+ 3d 5/2 , and Mo 4+ 3d 3/2 state of 2H-MoS 2 , respectively.…”

“…The reduced lifetime of nanoflowers is due to the increase of edge sites. Thus, the decreased lifetime of the MoS 2 nanoflowers infers that unsaturated S-edges could act as an electron trap and improve electron–hole separation …”

2D Free‐Standing Nitrogen‐Doped Ni‐Ni3S2@Carbon Nanoplates Derived from Metal–Organic Frameworks for Enhanced Oxygen Evolution Reaction

“…2D nanomaterials have received increasing interest due to their unique dimensional‐related physical and chemical properties in recent years . Typical 2D nanomaterials such as graphene, MoS 2 , and layered hydroxide nanosheets are widely investigated and applied in the field of electronics, energy storage, sensing, and catalysis . Based on various synthetic strategies toward 2D materials, the assemble of free‐standing 2D metal–organic frameworks (MOFs) have attracted tremendous attention due to the high surface area, regular pores, and unsaturated open sites inherited from their parent MOF crystals .…”

Progress in Electrocatalytic Hydrogen Evolution Based on Monolayer Molybdenum Disulfide

“…At present, there are two kinds of methods for preparing monolayer MoS 2 . The first method is top-down approach, including mechanical stripping (Li et al, 2012 ), ion intercalation (Nurdiwijayanto et al, 2018 ) and liquid phase stripping (Zhao et al, 2016 ), and the second one is bottom-up approach, including chemical vapor deposition(CVD) (Liu et al, 2018 ) and wet chemical stripping (Zeng et al, 2017 ). The development strategy of sustainable energy pattern and catalyst based on the electrocatalysis are shown in Figure 1 .…”