Xiamen University

About: Xiamen University is a education organization based out in Amoy, Fujian, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 50472 authors who have published 54480 publications receiving 1058239 citations. The organization is also known as: Amoy University & Xiàmén Dàxué.

Uniform Ordered Two-Dimensional Mesoporous TiO2 Nanosheets from Hydrothermal-Induced Solvent-Confined Monomicelle Assembly

Abstract: Two-dimensional (2D) nanomaterials have been the focus of substantial research interest recently owing to their fascinating and excellent properties. However, 2D porous materials have remained quite rare due to the difficulty of creating pores in 2D nanostructures. Here, we have synthesized a novel type of single-layered 2D mesoporous TiO2 nanosheets with very uniform size and thickness as well as ordered mesostructure from an unprecedented hydrothermal-induced solvent-confined assembly approach. The F127/TiO2 spherical monomicelles are first formed and redispersed in ethanol and glycerol, followed by a hydrothermal treatment to assemble these subunits into single-layered 2D mesostructure owing to the confinement effect of highly adhered glycerol solvent. The obtained 2D mesoporous TiO2 nanosheets have a relative mean size at around 500 × 500 nm and can be randomly stacked into a bulk. The TiO2 nanosheets possess only one layer of ordered mesopores with a pore size of 4.0 nm, a very high surface area of 2...

Hierarchical Integration of Photosensitizing Metal-Organic Frameworks and Nickel-Containing Polyoxometalates for Efficient Visible-Light-Driven Hydrogen Evolution.

Abstract: Metal–organic frameworks (MOFs) provide a tunable platform for hierarchically integrating multiple components to effect synergistic functions that cannot be achieved in solution. Here we report the encapsulation of a Ni-containing polyoxometalate (POM) [Ni4(H2O)2(PW9O34)2]10− (Ni4P2) into two highly stable and porous phosphorescent MOFs. The proximity of Ni4P2 to multiple photosensitizers in Ni4P2@MOF allows for facile multi-electron transfer to enable efficient visible-light-driven hydrogen evolution reaction (HER) with turnover numbers as high as 1476. Photophysical and electrochemical studies established the oxidative quenching of the excited photosensitizer by Ni4P2 as the initiating step of HER and explained the drastic catalytic activity difference of the two POM@MOFs. Our work shows that POM@MOF assemblies not only provide a tunable platform for designing highly effective photocatalytic HER catalysts but also facilitate detailed mechanistic understanding of HER processes.