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Noble metal nanocrystals (Au, Pt or AuPt) with controlled compositions and nanostructures were embedded into hollow silica submicrospheres with highly ordered radial mesopores through a one-step sol–gel process. 2,4-Dihydroxybenzoic acid–formaldehyde (RF-COOH) resin submicrospheres were utilized simultaneously as a hard template to create hollow interiors inside the silica submicrospheres and as carriers to transport pregrown metal nanocrystals, including Au nanoparticle (NP), Pt NP, and AuPt nanoalloy, into the submicrospheres. Calcination removes the resin submicrospheres and causes metal nanocrystals embedded into the RF-COOH submicrospheres break into multiple smaller nanoparticles (2–6 nm) that are randomly dispersed in the hollow space of SiO 2 submicrospheres M@SiO 2 (M = Au, Pt or AuPt). The AuPt@SiO 2 submicrospheres showed good catalytic performance for epoxidation of styrene with the conversion and selectivity of 74% and 85%, respectively. The approach reported in this study could potentially be used to simplify the fabrication process of noble metal nanoalloys, which usually entails multiple steps and a previously synthesized hard metal template, and thus guide the design and creation of high-performance catalysts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Preparation of PP-TiO2/CA microspheres with improved photoactivity. [•] The combined PP-TiO2/CA microsphere–membrane system preventing membrane fouling. [•] Recycling of PP-TiO2/CA by free settling method without energy consumption. [•] High permeation flux of 90L/m2 h for the combined microsphere–membrane system. [•] Force analysis revealing the suspending state of the microspheres in dye solution. [Copyright &y& Elsevier]

Highlights: [•] Preparation of new macroporous PPy TiO2 composite materials. [•] Stabilized organic–inorganic interface for improved charge injection and separation. [•] Enhanced visible light photoactivity and photoelectrical response. [•] Photocatalytic mechanisms under UV and visible light were discussed respectively. [Copyright &y& Elsevier]

In this work, for the first time, a typical catalysis–membrane system was designed for highly efficient H 2 generation from catalytic hydrolysis of NH 3 BH 3 (AB). The Pt nanoparticles (NPs) were tightly deposited on RF (resin microspheres) surface and the Pt@RF microspheres were then uniformly confined in the macroporous framework of a poly (vinylidene fluoride) hollow fiber membrane (PVDF). Compared with the previous reports, granular catalysts can be easily recycled and reused in our catalysis–membrane system. Furthermore, the circular solution in the membrane module could flush away the adsorbed metaborate on the Pt NPs, preventing passivation of the Pt NPs and increasing the accessibility of the active sites. In addition, the activation energy of the system was calculated to be only 13.69 kJ · mol −1 , smaller than those of the previous noble metal catalysts or non-noble metal-based catalysts for the same reaction, indicating the superior catalytic performance of the membrane module. Due to the high activity, circular reaction system, and macroporous membrane support, a high H 2 generation rate of 258.1 mol H 2 /(mol cat · min · m 2 membrane) was obtained for the catalysis–membrane module. Moreover, catalytic efficiency of the system remains well after 60 days. For its easy operation, good recyclability, durability and longevity, it is believed that the catalyst–membrane system can be easily scaled up for practical H 2 generation, leading to applications for AB in the field of fuel cells and guiding new design of highly efficient catalysis module. [ABSTRACT FROM AUTHOR]