| Abstract
| - In this paper, we bring forward an effective strategy, solvothermal postsynthesis, to prepareordered mesoporous silica materials with highly branched channels. Structural characterizations indicatethat the titled mesoporous materials basically have the cubic double gyroidal (space group Ia-3d) structurewith small fraction of distortions. The mesopore sizes and surface areas can be up to 8.8 nm and 540m2/g, respectively, when microwave digestion is employed to remove the organic templates. A phasetransition model is proposed, and possible explanations for the successful phase transition are elucidated.The results show that the flexible inorganic framework, high content of organic matrix, and nonpenetrationof poly(ethylene oxide) segments may facilitate the structural evolution. This new synthetic strategy canalso be extended to the preparation of other double gyroidal silica-based mesoporous materials, such asmetal and nonmetal ions doped silica and organo-functionalized silica materials. The prepared 3Dmesoporous silica can be further utilized to fabricate various ordered crystalline gyroidal metal oxide“negatives”. The mesorelief “negatives” (Co3O4 and In2O3 are detailed here) prepared by impregnationand thermolysis procedures exhibit undisplaced, displaced, and uncoupled enantiomeric gyroidal subframeworks. It has been found that the amount of metal oxide precursors (hydrated metal nitrates) greatlyinfluence the (sub)framework structure and single crystallinity of the mesorelief metal oxide particles. Thesingle crystalline gyroidal metal oxides are ordered both at mesoscale and atomic scale. However, theseorders are not commensurate with each other.
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