Bioinspired hollow and hierarchically porous MOx(M =Ti, Si)/carbon microellipsoids supported with Fe2O3 for heterogenous photochemical oxidation

•Hollow/hierarchical porous MOx(M = Ti, Si)/C was prepared by biotemplating technique.•Lilium pollen played as template and carbon source to promote charge transfer.•High surface area and multiple pore size distribution made more NPs well-dispersed.•Fe2O3@MOx(M = Ti, Si)/C exhibited much higher activity than conventional materials.•Multiple structure and unique support had positive effect on catalytic performance.

Porous carbon materials as a class of highly promising functional materials have attracted widespread interests. However, rational design and synthesis of carbon supported catalysts for long-term use still remains a big challenge. Herein, a facile surface sol-gel coating method via biotemplating technique was first employed to prepare hollow and hierarchically porous MOx(M = Ti, Si)/carbon microellipsoids with immobilized Fe2O3 NPs in pores. The easily-reached and carbon-rich pollen was chosen to play duple roles as both template and carbon source. The obtained natural carbon materials acted as trapping centers for photo-induced electrons and effectively improved visible-light photocatalytic activity and stability. By using this method, we can not only fabricate very active and reusable heterogenous catalysts without any additional surfactants, but also obviously reduce the fabrication time, dosage of chemicals and thickness of inorganic colloids. Since the bioinspired structure can provide high surface area and multiple pore size distribution for NPs to homogeneously disperse on the wall of carbon-based composites, the approach can be applied more generally to various biomaterials.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide