작성자 최고관리자 | 작성일 2015-06-17 00:07:14 | 조회수 1069
Solar Energy Materials and Solar Cells, 140 (2015): 141-149.
Muhammad Bilal Qadira, Kyung Chul Sunb, Iftikhar Ali Sahito, Alvira Ayoub Arbab, Bum Jin Choi, Sung Chul Yi*, Sung Hoon Jeong*
Light scattering in dye-sensitized solar cell (DSSC) plays a vital role in extending the traveling distance by confining light propagation within the photoanode and also promotes interaction of incident photons with the dye molecules. A novel strategy was adopted to improve the performance of DSSC with better absorption of solar spectrum both in the visible as well as near IR regions. A double layer photoanode structure with TiO2 nanoparticles (P25) as main layer and composite of titanium nanotubes (TNTs) and P25 as over-layer was introduced. Three different compositions of TNT/P25 were investigated, and finally an optimized composition with excellent performance was prepared. Performance of cells having composite over-layer was compared with the cells having TNT and conventional bigger particles (G2) over-layers. Composite over-layer structure of 75/25-TNT/P25 showed best photovoltaic performance of 8.52% with Jsc of 16.49 mA/cm2, which is 7.30% higher than the cells having G2 over-layer and 4.9% higher than the cells having pure TNT over-layer. Different characterization analysis proved that DSSC with optimized composite over-layer structure has significant advantages of better dye adsorption, large surface area, better photo-electron generation, superior electron recombination restraint characteristics, better conductive behavior, better light scattering, and long electron lifetime. Composite over-layer structure is a promising and innovative approach for further improving the efficiency of DSSC and this will be a concrete fundamental background toward the development of the applications of the next generation dye-sensitized solar cells.