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Two pairs of enantiomerically pure three-dimensional (3D) chiral polyoxometalate (POM) framework materials l,d-[K(H2O)]6·[H2GeW12O40]3·35H2O (1a and 1b) and l,d-[K(H2O)]6·[H2SiW12O40]3·29H2O (2a and 2b) based on inorganic achiral building blocks, have been synthesized and characterized by X-ray crystallography, elemental analysis, powder X-ray diffraction (PXRD), UV-Vis spectroscopy, circular dichroism (CD) spectra. Single-crystal X-ray diffraction analyses revealed that 1a and 1b, 2a and 2b are enantiomers, respectively. In 1a and 1b, 2a and 2b, {K(H2O)}n link terminal oxygen and μ2-bridging oxygen of Keggin-type polyanion moieties to generate 1D 31 helical infinite chiral chains, which are further connected by the achiral Keggin-type polyoxoanions to form 3D 4,8-connected chiral self-assembly frameworks with {4(12)·6(10)·8(6)}{4(6)}2 topology. 1 and 2 are isostructural. They are obtained by spontaneous resolution upon crystallization in the absence of any chiral source. They represent new examples of chiral self-penetrating pure inorganic frameworks known for POM systems. Compounds 1 and 2 display adsorption activity toward volatile organic compounds (VOCs).

Different nickel particle morphologies, including spheres, chains and urchins, were achieved in ethylene glycol solvent upon simply tuning both the amount of water and NaOH. The synthesis route was based on a routine solvothermal technique, in which nickel chloride and hydrazine hydrate were the nickel source and reductant, respectively. The shape transformation might be induced by an accelerated reaction rate and a change of the polarity of the solvent. Owing to the various morphology, these three kinds of nickel particles presented different catalytic performance. The reduction of 4-nitrophenol by NaBH 4 as a typical catalytic model revealed that the urchin-like nickel particles behaved with the highest catalytic effect because of their unique structure with tips on the surface, which endowed much more active sites for the catalytic reaction. The good magnetic properties allowed these nickel particles to be readily recycled after application and they presented a much high cycling stability.

The redox reaction between KMnO4 and Ni was carried out on a chain‐like Ni surface under hydrothermal conditions and γ‐MnO2 nanosheets were produced through this facile route. The original Ni nanochains, as cores, dominated the final morphology of the composites with MnO2 nanosheets loaded on their surface. The uniform assemblies of MnO2, with large amounts of exposed sites, allowed them to be good candidates for application in various fields. The reduction of 4‐nitrophenol by NaBH4 was selected as model reaction to test the catalytic activity of the samples and the samples could also be made into electrodes for supercapacitor measurement. Both the results revealed the advantages of the γ‐MnO2 assembled on the Ni chain surfaces. Furthermore, the magnetic cores facilitated the recycling of the sample and increased the stability upon charge–discharge cycles.