摘要
通过两步法合成PbS量子点(QDs)修饰ZnO纳米片复合膜.首先利用电化学法在掺氟的SnO2导电玻璃(FTO)上生长ZnO纳米片,然后在ZnO纳米片上通过逐次化学浴法沉积PbS量子点形成PbS/ZnO复合膜.利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)详细表征了样品的表面形貌和晶体结构,并研究了PbS/ZnO复合膜作为量子点敏化太阳能电池光阳极的紫外可见吸收谱、光电化学性能和表面光电压谱.对比ZnO纳米片经PbS量子点修饰前后,发现PbS量子点修饰后光阳极的光吸收和光伏响应均从紫外区拓宽到了可见光区,同时光电化学性能有了显著提高,短路电流密度从敏化前的0.1 mA/cm2增加到0.7 mA/cm2,效率由0.04%增加到0.57%.与单一ZnO纳米片相比,PbS/ZnO复合膜的表面光伏响应强度明显增强,说明PbS与ZnO之间形成了有利于光生电荷分离的异质结,从而导致了PbS/ZnO复合膜光电性能的增加.
PbS quantum dots（QDs）/ZnO nanosheets composite films were synthesized via a two-step method.ZnO nanosheet films were firstly grown on fluorine-doped SnO2 conducting glass（FTO） by electrodeposition techniques,then PbS QDs were decorated on ZnO nanosheets to form composite films by sequential chemical bath deposition.The morphology and crystalline phase of obtained films were detailedly characterized by scanning electron microscope（SEM）,X-ray diffraction（XRD）.The UV-Vis absorption,photoelectrochemical and surface photovoltage properties of ZnO nanosheets and PbS QDs/ZnO nanosheets composite films were investigated respectively.The results show that the absorption and surface photovoltage response region of PbS QDs/ZnO nanosheets composite films are more abroad than that of pristine ZnO nanosheets,extended from UV to visible light region.The photoelectrochemical property of PbS QDs/ZnO nanosheets composite films is dramatically enhanced compared to non-decorated ZnO nanosheets films,from 0.1 to 0.7 mA/cm2 of short circuit current density（Jsc）,from 0.04% to 0.57% of convert efficiency.Compared with ZnO nanosheets,the surface photovoltage response intensity is enhanced in PbS QDs/ZnO nanosheets,indicating heterojunction formed between PbS and ZnO.Photo-generated charge can effectively separate through this heterojunction,that is the reason for enhancement in photoelectric properties of PbS QDs/ZnO nanosheets composite films.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第1期59-63,共5页
Journal of Inorganic Materials
基金
国家自然科学基金(50588201,50872116)
中央高校基本科研业务费专项基金(2009QK46,SWJTU09ZT24)
国家863计划(2007AA03Z203)
高等学校博士点专项科研基金(SRFDP200806130023)
长江学者与创新团队计划(IRT0751)~~
