Aqueous Crystallization Strategy for Metastableh-MoO3Crystals with Polyvinylpyrrolidone Induction

Boosting photocatalytic nitrogen reduction reaction by Jahn-Teller effect

Compared with traditional the Haber-Bosch process, photocatalytic ammonia production has attracted a considerable attention due to its advantages of low energy consumption and sustainability. In this work, we mainly study the photocatalytic nitrogen reduction reaction (NRR) on MoO3·0.55H2O and α-MoO3. Structure analysis shows that compared to α-MoO6, the [MoO6] octahedrons in MoO3·0.55H2O obviously distort (Jahn-Teller distortion), leading to the formation of Lewis acid active sites that favors the adsorption and activation of N2. X-ray photoelectron spectroscopy (XPS) further confirms the formation of more Mo5+ as Lewis acid active sites in MoO3·0.55H2O. Transient photocurrent, photoluminescence and electrochemical impedance spectra (EIS) confirmed that MoO3·0.55H2O has a higher charge separation and transfer efficiency than α-MoO3. Density functional theory (DFT) calculation further confirmed that the N2 adsorption on MoO3·0.55H2O is more favorable thermodynamically than that on α-MoO3. As a result, under visible light irradiation (λ ≥ 400 nm) for 60 min, an ammonia production rate of 88.6 μmol·gcat-1 was achieved on MoO3·0.55H2O, which is about 4.6 times higher than that on α-MoO3. In comparison to other photocatalysts, MoO3·0.55H2O exhibits an excellent photocatalytic NRR activity under visible light irradiation without using sacrificial agent. This work offers a new fundamental understanding to photocatalytic NRR from the viewpoint of crystal fine structure, which benefits designing efficient photocatalysts.

UV Photochromism in Transition Metal Oxides and Hybrid Materials

Limited levels of UV exposure can be beneficial to the human body. However, the UV radiation present in the atmosphere can be damaging if levels of exposure exceed safe limits which depend on the individual the skin color. Hence, UV photochromic materials that respond to UV light by changing their color are powerful tools to sense radiation safety limits. Photochromic materials comprise either organic materials, inorganic transition metal oxides, or a hybrid combination of both. The photochromic behavior largely relies on charge transfer mechanisms and electronic band structures. These factors can be influenced by the structure and morphology, fabrication, composition, hybridization, and preparation of the photochromic materials, among others. Significant challenges are involved in realizing rapid photochromic change, which is repeatable, reversible with low fatigue, and behaving according to the desired application requirements. These challenges also relate to finding the right synergy between the photochromic materials used, the environment it is being used for, and the objectives that need to be achieved. In this review, the principles and applications of photochromic processes for transition metal oxides and hybrid materials, photocatalytic applications, and the outlook in the context of commercialized sensors in this field are presented.

Molybdenum oxide nano-dumplings with excellent stability for photothermal cancer therapy and as a controlled release hydrogel

MoO_3−x is synthesized via a one-pot hydrothermal method, with excellent stability against aging, heat, laser exposure and chemical etching.

Effects of MoO3 crystalline structure of MoO3–SnO2 catalysts on selective oxidation of glycol dimethyl ether to 1,2-propandiol

Hexagonal, monoclinic and orthorhombic MoO₃ crystalline phases were prepared to explore rational design requirements of the MoO₃–SnO₂ structure that are beneficial for the reaction of glycol dimethyl ether to 1,2-propandiol.

Crystal facet tailoring arts in perovskite oxides

This review highlights various facet tailoring arts in perovskite structure oxides.