摘要
采用水热法在F-SnO2(FTO)导电玻璃上制备了一维TiO2纳米棒阵列,将一种两亲有机三苯胺染料M分子吸附在其表面,进而旋涂有机聚合物聚3-己基噻吩P3HT,构建结构为FTO/TiO2/M/P3HT/PEDOT:PSS/Au的杂化太阳电池.瞬态光电流谱反映在杂化电极中存在pn异质结.接触角测试表明TiO2表面吸附有机M分子后,亲水性表面转变为疏水性表面,利于与聚合物P3HT的进一步接触;稳态荧光发射光谱表明经修饰的杂化电极的荧光发射强度降低,由荧光衰减曲线拟合得到的荧光寿命降低,说明在TiO2与P3HT之间存在有效的电荷转移,电荷复合被抑制.电化学阻抗分析表明界面修饰后电子复合电阻和电子寿命增大.电池的特性参数均比界面修饰前有所提高,光电转换效率为1.61%.另外,对该电池的工作机理、电荷传输过程进行了初步探讨.
In this paper, highly ordered and vertically oriented one-dimensional TiO2 nanorod arrays were prepared firstly on F-SnO2(FTO) conductive glass by hydrothermal method, then an amphiphilic organic triphenylamine-type dye 2-(5-(4-(diphenylamino)benzylidene)-4-oxo-2-thioxothiazolidin-3-yl)acetic acid(M for short) was adsorbed on its surface. After spin-coating organic polymer poly(3-hexylthiophene)(P3HT for short), we fabricated the modified hybrid solar cell device with the structure of FTO/TiO2/M/P3HT/PEDOT:PSS/Au. The transient photocurrent of the electrodes reflects the pn heterojunction is existent indeed in the hybrid electrode. The contact angle changes from 13.9° for pure TiO2 to 112.6° for M-modified sample. This hydrophobic surface facilitates TiO2 further contacting with polymer P3 HT. The steady state photoluminescence(PL) emission spectra shows stronger quenching of PL intensity, and PL lifetime fitted from the PL decay curves decreased for the M-modified hybrid film. These conclusions implie the effective charge transfer between P3 HT and TiO2, which could suppress the charge recombination. Electrochemical impedance analysis showed that the electron recombination resistance and electron lifetime were increased after interfacial modification. The photovoltaic performance of the modified hybrid cell along with the unmodified one was tested. The open-circuit voltage(Voc), short-circuit current(Jsc), fill factor(FF) are increased for the modified device, and resulting the power conversion efficiency(η) of 1.61%. In addition, the mechanism of the cell and the charge transfer process were investigated preliminarily. The interfacial modifier might be functioned as a 'bridge' to transfer electrons to inorganic semiconductor, and transfer holes to polymer also. The modifier could possibly mediate charge transfer in one direction from P3 HT to TiO2 for electron accepting and result in more efficient charge separation due to the cascaded energy levels. This work may provide a useful method for increasing the performance of hybrid solar cells by interface modification.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2014年第12期1245-1250,共6页
Acta Chimica Sinica
基金
国家自然科学基金(No.21173065)
河北省自然科学基金(Nos.B2014208062
B2014208066
B2014208121)
河北省科技计划项目(No.13214413)
河北科技大学博士启动基金(Nos.QD201050
010087)资助~~
关键词
杂化太阳电池
界面修饰
激子分离效率
电荷复合
光电性能
hybrid solar cell
heterojunction interface modification
exciton dissociation efficiency
charge recombination
photovoltaic performance
