沸石负载Mn, N共掺杂TiO₂及光催化性能

In order to improve the visible light catalytic activity of traditional TiO₂ photocatalyst, Mn, N co-doped TiO₂ photocatalyst was synthesized by sol-gel method, which improved the problem of easy recombination of photogenerated carriers. Further, zeolite was used as a carrier to solve the problem of difficult separation and recovery of the conventional photocatalyst, achieving the purpose of reusable. The crystal phase structure, element composition, microtopography, and photocatalytic activity of TiO₂ photocatalyst were characterized by XRD, SEM, UV-vis, and FTIR. Results show that Mn, N co-doped TiO₂/zeolite composites had higher activity than pristine TiO₂. The degradation rate of malachite green in the TiO₂ photocatalyst obtained under optimal doping conditions could reach 97% within 60 min in visible light, which was because the manganese ion doping could inhibit the recombination of TiO₂ photogenerated carriers and promote charge separation. Meanwhile, nitrogen doping could effectively broaden the photoresponse range of TiO₂. Moreover, after five usage cycles of Mn, N co-doped TiO₂/zeolite composites, the degradation rate of malachite green was not greatly reduced, maintaining above 88%, which indicates that the Mn, N co-doped TiO₂/zeolite composites have good photocatalytic cycle stability.