NiCoP/CdS复合光催化剂的制备及其光催化产氢活性

Preparation of NiCoP/CdS and its photocatalytic activity in hydrogen evolution

为了提高CdS的产氢活性,采用溶剂热法制备了NiCoP/CdS纳米棒复合光催化剂。质量分数为3%NiCoP/CdS的产氢量达到47. 86 mmol/(g·h),是质量分数5%Pt/CdS产氢量的6. 9倍,是无助催化剂CdS的126倍。此外,NiCoP/CdS具有较好的光催化稳定性,在反应24 h后进行5次循环产氢测试,其产氢活性没有明显下降。稳态荧光光谱、时间分辨荧光光谱和瞬态光电流测试结果表明,复合后NiCoP/CdS荧光强度降低、荧光寿命减小、光电流增加,说明NiCoP的修饰能够有效促进光生电子和空穴的分离,进而提高NiCoP/CdS复合光催化剂的产氢活性。

To improve hydrogen evolution,NiCoP/CdS photo-catalyst is prepared by loading NiCoP onto CdS nanorods through solvothermal method.The results show that Ni Co P/Cd S exhibits excellent photocatalytic activity.The rate of hydrogen evolution over 3%NiCoP/CdS reaches 47.86 mmol/(g·h),which is 6.9 and 126 times higher than that over 5%Pt/CdS and pure Cd S,respectively.Furthermore,NiCoP/CdS exhibits a long-time stability for photocatalytic H2 production.The results show that there is no significant decline in hydrogen yield rate during 5 cycles of hydrogen production test after 24 hours of reaction.The steady-state fluorescence spectra,time-resolved fluorescence spectra and transient photocurrent tests show that both the fluorescence intensity and lifetime of NiCoP/CdS decrease,but its photocurrent increases when NiCoP is loaded onto the surface of CdS nanorods,indicating that NiCoP can greatly promote electron-hole pair to separate,which is favorable to improve the photocatalytic performance.