[20a-PB2-1~59] 12.5 Organic solar cells

[20a-PB2-25] Fabrication of electrodes using a mm size perovskite pellet and the effect of a TiO₂ layer on a FTO substrate on its current-voltage characteristics

〇Chiaki Yamaki¹, Yoshitaka Sanehira¹, Masashi Ikegami¹, Tsutomu Miyasaka¹ (1.Toin Univ. of Yokohama)

Keywords:perovskite solar cell, photoconductor, heat press

Perovskite solar cells have an outstanding energy conversion efficiency and hence, they can be utilized for photo sensing applications. The lead halide perovskite materials are sensitive to x-rays and γ- rays and therefore, can be used for the development of the x-rays and γ- rays sensors. For these applications, a material thickness of 1 mm is required because of its absorption coefficient. In solar cell applications, a material thickness of only 1 mm is required, so the fabrication methods for 1 mm material size are required to be developed. To produce 1 mm thickness pellet, we used a heat press equipment. First, we prepared a lead-halide perovskite (CH₃NH₃PbI₃) single crystal from 2 to 3 mm in size by using the so-called inverse temperature recrystallization. After that the crystals were placed into a dice of 7 mm diameter and then the weight of the crystals are measured. Further, the dice is pressed with a load of 2 kN using a heat press equipment with the top and bottom plates are heated at 100 ^oC. After 10 minutes, the dice was set out of the heat press equipment and a perovskite pellet is taken out from the dice. After measuring the thickness of the pellet, the density was calculated, and it was compared with the expected density of 4.2 g/cm³ of CH₃NH₃PbI₃.
This pellet was put by partially resolving with solvent on the FTO glass covered with TiO₂ layer of a certain thickness from 10 nm to 100 nm and a gold was deposited on the pellet. Finally, the current-voltage characteristics are measured, and they are observed to be consistent with that of a semi-conducting material.