Hwang, Daesub Lee, Horim Seo, Yongsok Kim, Dongho Jo, Seong Mu Kim, Dong Young 2024-01-20T13:04:36Z 2024-01-20T13:04:36Z 2021-09-01 2013-01 2050-7488 https://pubs.kist.re.kr/handle/201004/128502 Hierarchically structured mesoporous TiO2 beads (HS-TBs), which are used as photoelectrodes in highly efficient dye-sensitized solar cells (DSCs), were prepared by an electrostatic spray (e-spray) technique. To prepare different sized HS-TBs, the electric field and the concentration of TiO2 particles were carefully controlled, because they are critical factors in preparing size-controlled TiO2 beads. Four different HS-TBs were formulated with average diameters of 250, 450, 700, and 1200 nm as high-quality photoelectrodes for use in DSCs. In this study, we found that the zero-dimensional HS-TBs were the most promising photoelectrode for DSCs due to enhanced charge collection efficiency and better penetration of electrolytes through relatively large pores among the HS-TBs. The HS-TBs were characterized by intensity modulated photocurrent spectroscopy (IMPS), the scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) method, Barrett-Joyner-Halenda (BJH) method, and electrochemical analysis. The conversion efficiency of HS-TB photoelectrodes improved with increasing bead size due to the enhanced electron transport through electrodes. The present HS-TB cells exhibit a noticeable improvement in the overall efficiency: maximum 9.54% (1200 nm) versus 5.83% for the reference cell made of a TiO2 nanocrystalline film. English ROYAL SOC CHEMISTRY Enhanced charge collection efficiency of dye-sensitized solar cells based on size-tunable hierarchically structured TiO2 beads Article 10.1039/c2ta00292b 1 JOURNAL OF MATERIALS CHEMISTRY A, v.1, no.4, pp.1359 - 1367 JOURNAL OF MATERIALS CHEMISTRY A 1 4 1359 1367 N scie scopus 000314633500051 2-s2.0-84876584535 Chemistry, Physical Energy & Fuels Materials Science, Multidisciplinary Chemistry Energy & Fuels Materials Science Article ENERGY-CONVERSION ELECTRON-TRANSPORT PHOTOCURRENT SIMULATIONS TEMPERATURE FILM dye-sensitized solar cell TiO2 Hierarchically structured mesoporous bead electro-spray