Abstract:
The construction of hybrid heterojunction photocatalysts is an effective strategy to improve the utilization of photogenerated carriers and photocatalytic activity. To enhance the separation distance of photogenerated carriers and accelerate the effective separation at the heterojunction of the interface, a unique 0D-2D hierarchical nanostructured p-n heterojunction was successfully fabricated in this work. BiOCl (BOC) nanosheets (p-type) were in situ grown on BiVO4 (BVO) nanoparticles (n-type) using the microemulsion-calcination method for highly efficient visible-light-driven organic dye degradation. Compared with pure BVO (the degradation rate of rhodamine B (RhB): about 32.0% in 55 min, the mineralization rate: 24.9% in 120 min), the RhB degradation rate can reach about 99.5% in 55 min and the mineralization rate of 62.1% in 120 min by utilizing BVO/25%BOC heterojunction photocatalyst under visible light irradiation. Various characterizations demonstrate that the formation of BVO/BOC p-n heterojunction greatly facilitates photogenerated carriers separation efficiency. Meanwhile, the results of the scavenging experiments and electron spin resonance tests indicate that ·O2- and h+ are the prominent active species for Rh B degradation. In addition, possible degradation pathways for Rh B were proposed using LC-MS tests. This work proves that building low dimensional p-n heterojunction photocatalysts is a promising strategy for developing photocatalysts with high efficiency.
摘要:
构建混合异质结光催化剂是提高光生载流子利用率和光催化活性的有效策略。为了提高光生载流子的分离距离,加速界面异质结处的有效分离,在这项工作中成功地制造了一个独特的0D-2D分层纳米结构p-n异质结。使用微乳液煅烧方法在BiVO4(BVO)纳米颗粒(n型)上原位生长BiOCl(BOC)纳米片(p型),以实现高效的可见光驱动有机染料降解。与纯BVO相比(罗丹明B(RhB)的降解率:55分钟内约为32.0%,矿化率:120分钟内24.9%),在可见光照射下,利用BVO/25%BOC异质结光催化剂,RhB降解率在55分钟内达到99.5%左右,在120分钟内矿化率为62.1%。各种表征表明,BVO/BOCp-n异质结的形成极大地促进了光生载流子分离效率。同时,清除实验和电子自旋共振测试的结果表明,·O2-和h是RhB降解的主要活性物种。此外,使用LC-MS测试提出了RhB的可能降解途径。这项工作证明,建立低维p-n异质结光催化剂是开发高效光催化剂的有前途的策略。