金属Pd掺杂对MoS2/Si异质薄膜微结构和光伏性能的影响

摘要

Pd doping MoS2 (Pd:MoS2) thin films were deposited on the surface of Si substrates using DC magnetron sputtering technique,and Pd:MoS2/Si heterostructures were fabricated.In order to study the influence of the concentration (x％) of the Pd doping in the films on the microstructures and photovoltaic performance,Raman spectra were performed and J-V curves were measured.The results demonstrated that the peak position of A1g was shifted toward lower Raman shift direction due to the incorporation of Pd into the MoS2 films,while E12g peaks have no obvious change.The J-U results showed that the photovoltaic performance of the Pd:MoS2/Si heterostructures increased with increasing the Pd doping.When x =1,the optimum power conversion efficient was obtained,about 4.6％.When x further increased,the device performance decreased.By UV and UPS,the band alignment near the interface of the heterostructures were constructed and the influence mechanisms of Pd doping on the device performance were clarified.%采用直流磁控溅射技术,在Si表面沉积了Pd掺杂MoS2(Pd:MoS2)薄膜,形成了Pd:MoS2/Si异质薄膜太阳能电池器件,并综合利用拉曼光谱、紫外-可见光谱、紫外光电子能谱和伏安曲线测量等技术分析了Pd掺杂浓度(x％)对MoS2薄膜微结构及Pd:MoS2/Si异质薄膜器件光伏性能的影响.拉曼光谱结果表明,Pd掺杂明显改变了MoS2薄膜中A1g晶格振动,而几乎不影响E12g晶格振动.在模拟太阳光照射条件下,伏安性能测试结果显示:随着Pd掺杂浓度的增加,Pd:MoS2/Si异质薄膜器件的光伏性能显著增强;当x=1时,器件表现出最佳的光伏效果,转化效率达到4.6％;继续增加Pd掺杂浓度,器件的光伏性能则逐渐减弱.进一步通过紫外-可见光光谱和紫外光电子能谱分析,构建了Pd:MoS2/Si界面能带结构,阐释了Pd掺杂对器件光伏性能的影响机制.