Abstract:
Employing naturally extracted dyes and their derivatives as photosensitizers towards the construction of dye-sensitized solar cells (DSSCs) has been recently emerging for establishing sustainable energy conversion devices. In this present work, Rhodobacter Sphaeroides Photobacteria (Rh. Sphaeroides) was used as a natural source from which Bacteriopheophytine-a (Bhcl) dye was extracted. Further, two cationic derivatives of Bhcl, viz., Guanidino-bacteriopheophorbide-a (Gua-Bhcl) and (2-aminoethyl)triphenylphosphono-bacteriopheophorbide-a (2AETPPh-Bhcl) were synthesized. The thus obtained Bhcl, Gua-Bhcl and 2AETPPh-Bhcl were characterized using liquid chromatography-mass spectrometry (LC-MS) and their photophysical properties were investigated using excitation and emission studies. All three near-infrared (NIR) responsive dyes were employed as natural sensitizers towards the construction of DSSC devices, using platinum as a photocathode, dye-sensitized P25-TiO2 as a photoanode and I-/I3- as an electrolyte. DSSCs fabricated using all three dyes have shown reasonably good photovoltaic performance, among which 2AETPPh-Bhcl dye has shown a relatively higher power conversion efficiency (η) of 0.38% with a short circuit photocurrent density (JSC) of 1.03 mA cm-2. This could be attributed to the dye\'s natural optimal light absorption in the visible and NIR region and uniform dispersion through the electrostatic interaction of the cationic derivatives on the TiO2 photoanode. Furthermore, the atomic force microscopy studies and electrochemical investigations using cyclic voltammetry, electrochemical impedance spectroscopy and Bode\'s plot also supported the enhancement in performance attained with 2AETPPh-Bhcl dye.
摘要:
使用天然提取的染料及其衍生物作为光敏剂来构建染料敏化太阳能电池(DSSC)最近已经出现,用于建立可持续的能量转换设备。在目前的工作中,球形红杆菌属光细菌(Rh。Sphaeroides)被用作天然来源,从中提取了芽孢杆菌-a(Bhcl)染料。Further,Bhcl的两种阳离子衍生物,viz.,合成了胍基-细菌heophorbide-a(Gua-Bhcl)和(2-氨基乙基)三苯基膦酰基-细菌heophorbide-a(2AETPPh-Bhcl)。如此获得的Bhcl,使用液相色谱-质谱(LC-MS)表征了Gua-Bhcl和2AETPPh-Bhcl,并使用激发和发射研究研究了它们的光物理性质。所有三种近红外(NIR)响应染料均用作DSSC设备构建的天然敏化剂,用铂做光电阴极,染料敏化的P25-TiO2作为光电阳极和I-/I3-作为电解质。使用所有三种染料制造的DSSC显示出相当好的光伏性能,其中2AETPPh-Bhcl染料显示出相对较高的功率转换效率(η),为0.38%,短路光电流密度(JSC)为1.03mAcm-2。这可以归因于染料在可见光和近红外区域的自然最佳光吸收以及通过阳离子衍生物在TiO2光阳极上的静电相互作用的均匀分散。此外,原子力显微镜研究和电化学研究使用循环伏安法,电化学阻抗谱和Bode's图也支持使用2AETPPh-Bhcl染料获得的性能增强。