竹炭负载氧空位型BiOI/BiOCl复合光催化剂脱硝机理

Mechanism for NO_x removal over the bamboo charcoal supported BiOI/BiOCl composite photocatalyst with oxygen vacancy

以竹炭为载体,采用溶剂热法制备了氧空位(OV)型BiOI/BiOCl光催化剂,考察了温度和光照强度对其催化脱硝性能的影响,采用SEM、XPS、XRD、PL、Uv-vis等表征方法研究了该复合光催化剂上的脱硝机理。结果表明,在氙灯功率500 W、温度30℃时,最佳脱硝效率可达73%。氧空位改性可以增大竹炭的比表面积和孔容,提高其吸附能力,同时使C=O双键和-COO形式的酸性官能团分解为C-O官能团;OV改性还增加了光催化活性位点,减少了电子空穴对复合概率,从而提高了对NO的光催化降解效率。

BiOI/BiOCl composite photocatalysts with oxygen vacancy（OV） were successfully synthesized by solvothermal method with bamboo charcoal（BC） as the carrier. The effect of temperature and light on the catalytic performance in the removal of NOx was considered and the photocatalytic reaction mechanism was investigated with the assistance of SEM,XPS,XRD,PL and Uv-vis analysis. The results indicated that optimum denitrification efficiency of 73% can be achieved under 30 ℃ and with a xenon lamp of 500 W. After the modification with the OV agents,the specific surface area and pore capacity of BC were greatly enhanced; the adsorption capacity was also improved and the functional groups of C = O and-COO can be efficiently broken into C-O functional groups. Meanwhile,the modification with OV agents can increase the photocatalytically active sites,reduce the recombination rate of electron hole pairs,and thus improve the efficiency of NO photocatalytic degradation.