Sb_2S_3纳米丝的合成及杂化太阳电池研究

Synthesis of Sb_2S_3 Nanowires and Their Application in Hybrid Solar Cells

利用溶剂热方法制备出高质量的Sb2S3纳米丝,并将其与聚(2-甲氧基-5-(2-乙基己氧基)-1,4-对苯乙炔)(MEH-PPV)共混制备成体型结构聚合物太阳电池.利用X射线衍射、扫描电子显微镜、透射电子显微镜和紫外-可见吸收光谱对Sb2S3纳米丝进行表征,利用电流-电压(J-V)测试和电池的光电转换效率(IPCE)谱研究了Sb2S3纳米丝含量对Sb2S3/MEH-PPV共混体型结构太阳电池性能的影响.结果表明,合成的Sb2S3纳米丝直径为60～70 nm,长度为4～6μm,沿[001]晶向生长,在紫外-可见光区有较强的吸收,光学带隙为1.57 eV.电池性能测试结果表明,Sb2S3纳米丝作为辅助光吸收材料及有效的电子传输材料,提高了对可见光的利用率;Sb2S3的补充吸收作用使Sb2S3/MEH-PPV共混电池具有一定的宽谱响应特点;与不含Sb2S3的电池相比,Sb2S3/MEH-PPV共混电池中增加的MEH-PPV/Sb2S3界面提高了光生激子分离效率,从而提高了电池的效率.

High quality Sb2S3 nanowires, which were 60-70 nm in diameter and 4---6 in length, were synthesized via a facile solvothermal approach by using L-eysteine （C3H7 NO2S） as a capping agent, and applied to hybrid solar ceils after blending with poly（2-methoxy-5-（2-ethylhexyloxy）-i ,4-phenylenevinylene） （MEH-PPV）. The as-synthesized nanowires were characterized by XRD, SEM, TEM, UV-Vis absorption and PL spectra; the solar cells were investigated by current-voltage （J-V） measurements and incident photon-to- current conversion efficiency （IPCE） spectroscopy. The highly pure Sb2S3 nanowires have a bandgap of i. 57 eV and grow along [001 ] direction. In comparison with the solar cells without Sb2S3 nanowires, the MEH- PPV/Sb2S3deviees exhibit a much higher Jso depending on the Sb2S3 concentration and a certain wide spectral response characteristics due to complementary absorption of Sb2S3 nanowires. With addition of the Sb2S3 nanowires into the polymer phase, the MEH-PPV/Sb2S3 interfaces are created for dissociation of the excitons generated in the polymer and the direct channels are formed for electron transport; on the other hand, the de- fects on the nanowire surface cause the serious charge recombination that is unfavorable for the photocurrent generation. At the Sb2S3/MEH-PPV mass ratio of 5 ： 1, the device with a power conversion efficiency of 0. 393% is achieved under AM 1.5 illumination（100 roW/era2）.