Double-layered TiO2 cavity/nanoparticle photoelectrodes for efficient dye-sensitized solar cells

• Published in: Frontiers of materials science Vol. 17; no. 1
• Main Authors: Li, Zhen, Yu, Libo
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 01.03.2023; Springer Nature B.V
• Subjects: Chemistry and Materials Science; Circuits; Dye-sensitized solar cells; Dyes; Electrodes; Energy conversion efficiency; Holes; Light scattering; Materials Science; Microspheres; Nanoparticles; Photovoltaic cells; Research Article; Short circuit currents; Titanium dioxide; titanium dioxide; light scattering; cavity; dye sensitized solar cell
• ISSN: 2095-025X; 2095-0268
• DOI: 10.1007/s11706-023-0638-8

TiO 2 nanoparticles (NPs) in the size of ∼25 nm, namely P25, are very common material as the electron collecting layer in dye-sensitized solar cells (DSSCs). However, the light-scattering improvement of TiO 2 NP photoelectrodes is still a challenge. Here, we built TiO 2 cavities on the top of the TiO 2 NP layer by using carbonaceous microspheres as the template, forming the TiO 2 cavity/nanoparticle (C/NP) photoelectrode for the application in DSSCs. The cavity amount in the TiO 2 C/NP photoelectrode was controlled by adjusting the weight ratio of carbonaceous microspheres. SEM results confirm the successful formation of the double-layered TiO 2 C/NP electrode. J—V tests show that the optimized TiO 2 C/NP electrode prepared with 25 wt.% carbonaceous microspheres contributes to remarkable improvement of the short-circuit current density ( J sc ) and the power conversion efficiency (PCE). The best photovoltaic performance solar cell with the PCE of 9.08% is achieved with the optimized TiO 2 C/NP photoelectrode, which is over 98% higher than that of the TiO 2 NP photoelectrode. Further investigations of UV-vis DRS, IPCE, OCVD, and EIS demonstrate that the competition between light scattering effect and charges recombination in this TiO 2 C/NP photoelectrode is responsible for the PCE enhancement.