Macroporous-mesoporous C-,S-,N-doped titania microspheres via the polyHIPE microspheres templates

Doping and increasing specific surface area by forming highly porous structures are two effective ways to enhance the photocatalytic performances of TiO_2 particles.He re for the first time,we report a new facile method to prepare the macroporous-mesoporous C-,S-,N-doped TiO_2(C/S/N-TiO_2) microspheres via polyHIPE microsphe res as templates.The chemical and crystalline structure s of these hierarchical porous TiO_2 microspheres are analyzed with FTIR,XPS,EDS,and XRD.The macroporous-mesoporous structures are confirmed with SEM observation and BET analysis.UV-vis DRS spectra analysis shows that the band gaps of C doped TiO_2,C/N doped TiO_2,C/S doped TiO_2 and C/S/N doped TiO_2 are estimated to be 3.07,3.01,2.94 and 2.81 eV,respectively,which are significantly narrower than that of TiO_2 nanoparticles(3.23 eV).Photoluminescence spectra demonstrate that the recombination of electrons and holes in these macroporous-mesoporous TiO_2 microspheres is also suppressed.The hierarchical porous C/S/N-TiO_2 microspheres show high visible-light catalytic efficiency and excellent cycling stability to degrade RhB dye.