Eur. Phys. J. Plus (2020) 135: 195
https://doi.org/10.1140/epjp/s13360-020-00241-x

Regular Article

Highly porous film of TiO₂ nanoparticles synthesized using carbon nanospheres for highly efficient dye-sensitized solar cells

¹ Department of Physics, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
² Department of Engineering, Tarbiat Modares University, P.O. Box 14155-4838, Tehran, Iran

^* e-mail: saievare@modares.ac.ir

Received: 6 October 2019
Accepted: 20 January 2020
Published online: 3 February 2020

Abstract

Highly porous films of TiO₂ nanoparticles were prepared by a doctor blade method using carbon nanospheres as a porosity enhancer. At first, carbon nanospheres with a diameter ranging from 100 to 600 nm were synthesized by a hydrothermal method; then, a paste of TiO₂ nanoparticles was mixed with various amounts of carbon nanospheres. To obtain a porous TiO₂ nanoparticles photoanode and removing carbon nanospheres, photoanode was sintered at a temperature of 500 °C. XRD patterns and Raman analysis revealed the anatase phase of TiO₂ and show that the carbon spheres acted only as a porosity enhancer. Removing carbon nanospheres leads to the creation of cavities with various sizes in dye-sensitized solar cells (DSSCs). Under illumination, these random cavities increase porosity and light scattering of the photoanode which leads to a larger surface area for dye loading and improve light absorbance by dye N719 and consequently enhance the performance of DSSCs. For the optimum sample by mixing 3 wt% carbon nanospheres in the TiO₂ pastes, the efficiency (η) and short-circuit current density (J _sc) were increased by 33% (from 5.72 to 7.59%) and 40% (from 12.59 to 17.73 mA cm⁻²), respectively.