Munir Shamsa, Shah Syed Mujtaba, Hussain Hazrat, Siddiq Muhammad
Department Of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
Department Of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
J Photochem Photobiol B. 2015 Dec;153:397-404. doi: 10.1016/j.jphotobiol.2015.10.029. Epub 2015 Oct 30.
A photo-active nano-hybrid material consisting of titania nanoparticles, carminic acid, and sulphonic acid functionalized porphyrin is reported here. In an attempt to extend the absorption spectrum of titania to visible region by co-adsorbing carminic acid and sulphonic acid functionalized porphyrin on its surface. Interesting changes in the UV-visible and fluorescence spectra were noticed. The adsorption of carminic acid resulted in the formation of charge transfer complex with titania nanoparticles. This was confirmed by the electronic absorption and fluorescence emission spectroscopies. Chemisorption of porphyrin on the carminic acid functionalized titania further boosted the charge transfer effect. This was noticed by the increase in intensity and width of the charge transfer absorption and emission bands. Energy level diagram showed that the interaction among the constituents of the nano-hybrid assembly permitted the flow of electron in a cascade manner from carminic acid to TiO2.This also allowed direct flow of electrons either from carminic acid or porphyrin toward titania. The material was used as an active blend in hybrid bulk heterojunction solar cells. Co-functionalized TiO2-based devices were found 3.5 times more efficient than the reference device but morphology of the device proved a major setback.
本文报道了一种由二氧化钛纳米颗粒、胭脂红酸和磺酸官能化卟啉组成的光活性纳米杂化材料。通过在二氧化钛表面共吸附胭脂红酸和磺酸官能化卟啉，试图将二氧化钛的吸收光谱扩展到可见光区域。紫外可见光谱和荧光光谱出现了有趣的变化。胭脂红酸的吸附导致与二氧化钛纳米颗粒形成电荷转移络合物。这通过电子吸收光谱和荧光发射光谱得到证实。卟啉在胭脂红酸官能化的二氧化钛上的化学吸附进一步增强了电荷转移效应。这通过电荷转移吸收和发射带的强度和宽度增加得以体现。能级图表明，纳米杂化组件各成分之间的相互作用使得电子能够以级联方式从胭脂红酸流向二氧化钛。这也允许电子直接从胭脂红酸或卟啉流向二氧化钛。该材料被用作混合体异质结太阳能电池中的活性共混物。发现基于共官能化二氧化钛的器件效率比参考器件高3.5倍，但器件的形态证明是一个主要障碍。
