N掺杂Bi_2O_2CO_3/氧化石墨烯分级结构的合成及其可见光催化性能研究

Synthesis and Visible Light Photocatalytic Performance of N-doped Bi_2O_2CO_3/ Graphene Oxide Hierarchical Structure

以柠檬酸铋铵分子为前驱体,采用一步水热法直接合成了原位N掺杂Bi2O2CO3分级微球(由二维级别纳米片组装而成的三维级别的维度分级结构)及其与氧化石墨烯(GO)的复合材料。柠檬酸铋铵在水热过程分解出的NH+4为N掺杂唯一来源,柠檬酸根在水热过程中分解产生CO2-3,部分Bi3+被还原成Bi单质。通过N掺杂以及GO的引入,使Bi2O2CO3的光响应范围扩展至可见光,降低了Bi2O2CO3的禁带宽度。Bi单质使复合材料具备更低的电子-空穴复合率。可见光照射下,N掺杂Bi2O2CO3分级微球表现出良好的光催化去除NO的性能。引入氧化石墨烯和Bi单质后,光催化活性进一步得到提升。

In situ N-doped Bi2O2CO3/ graphene oxide hierarchical microspheres were fabricated by a onepot hydrothermal method using ammonium bismuth citrate as the single precursor. During the hydrothermal process,the NH＋4generated by the decomposition of the ammonium bismuth citrate was the only N doping source,the CO2-3was generated by the decomposition of citrate,and part of the Bi3 ＋were reduced to Bi element. The N doping and the introduction of the GO（ graphene oxide） together made the light response spectra of Bi2O2CO3 extend into visible light region significantly and reduce the band gap of Bi2O2CO3. The existence of Bi resulted in a remarkable lowered recombination rate of electron-hole pairs. Under visible light irradiation,the N-doped Bi2O2CO3 hierarchical microspheres structure showed an excellent photocatalytic activity toward NO removal. The photocatalytic activity could be further enhanced after the introduction of graphene oxide and Bi.