钴掺杂聚合氮化碳光催化还原二氧化碳性能研究

聚合氮化碳(CN)具有可见光响应、化学性质稳定、廉价易得、无毒等优点，在光催化领域得到了广泛的研究和应用，但是存在比表面积较小、电子-空穴对易复合等不足之处，严重限制了其光催化性能。以尿素和常见的两种钴盐CoCl₂和Co(NO₃)₂]为前驱体，通过一步煅烧法制备了钴(Co)掺杂CN，研究了不同Co源对材料光催化还原二氧化碳(CO₂)性能的影响。实验证明，由适量氯化钴(CoCl₂)为Co源得到的Co掺杂CN，其光催化还原CO₂生成一氧化碳(CO)的速率可由纯CN的82.7μmol/(g·h)提升至374.5μmol/(g·h)，同时CO选择性由79.1%提高至88.5%；而以硝酸钴Co(NO₃)₂]为Co源得到的Co掺杂CN倾向于产氢，其光催化还原CO₂性能基本不能得到提升。通过对光催化剂进行电感耦合等离子体(ICP)、X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、X射线光电子能谱(...

Study on photocatalytic CO2 reduction performance of Co doped polymeric carbon nitride

Polymeric carbon nitride（CN） has been widely studied and applied in the field of photocatalysis benefiting from its visible light response，high chemical stability，low cost，easy preparation and non-toxicity.However，its shortcomings，such as small specific surface area and easy recombination of electron-hole pairs，seriously limit its photocatalytic performance.Co doped CN was prepared by one-step calcination of urea and two widely used cobalt saltsCoCl₂ and Co（NO₃）₂] as precursors，and the effects of different Co sources on the photocatalytic CO₂ reduction performance of the products were studied.The results showed that the photocatalytic CO₂ reduction performance of CN doped with appropriate amount of Co by using CoCl₂ as Co source was improved.The CO generation rate was increased from 82.7 μmol/（g·h）for pure CN to 374.5 μmol/（g·h），and the CO selectivity was increased from 79.1% to 88.5%.By contrast，Co doped CN using Co（NO₃）₂ as Co source was tended to produce hydrogen，and its photocatalytic CO₂ reduction performance was not improved.The photocatalysts were characterized by inductively coupled plasma（ICP），X-ray diffraction（XRD），fourier infrared spectroscopy（FT-IR），X-ray photoelectron spectroscopy（XPS），UV-Vis diffusion reflection spectroscopy（UV-Vis DRS），scanning electron microscopy（SEM），physical adsorption，photoelectrochemical test and etc.，and the material structure and the reasons for the improvement of the photocatalytic performance were analyzed.