Title:	Cesium-Containing Triple Cation Perovskites as Tandem Partners for Silicon Solar Cells
Author(s):	S. Ašmontas, J. Gradauskas, A. Griguceviciene, K. Leinartas, K. Petrauskas, A. Selskis, A. Sužiedelis, E. Širmulis
Topic:	Perovskites and Other Non-Silicon Materials, MJs and Tandems
Subtopic:	Tandems
Event:	37th European Photovoltaic Solar Energy Conference and Exhibition
Session:	3BV.2.93
ISBN:	3-936338-73-6
Price:	0,00 EUR
Document(s):	poster

Abstract/Summary:

---

Successful development of monolithic perovskite/silicon tandem solar cell has attracted considerable attention during past few years [1–6]. The interest is motivated by the rapid development of power conversion efficiency of perovskite solar cell from less than 3.8% to above 22% in the last decade [6,7]. To create a tandem perovskite/silicon solar cell, the perovskite layer must well absorb visible light and be transparent to the infrared light. Triple cation perovskites of the general form „Csx(MA0.17FA0.83)(100-x)Pb (I0.83Br0.17)3“ developed in [8] can be suitable candidates as tandem partners for silicon solar cells. In this communication, we present experimental study of optical properties of perovskite layers with different cesium concentration as well as photoelectric properties of solar cells fabricated on their base. The perovskite layers were formed by a one-step deposition method from the precursor solution produced. Anhydrous N,N-dimethylformamide/dimethylsulfoxide (DMF / DMSO), 4:1 by volume, was used as a solvent. Material concentrations of the prepared solution were: 1 M of formamide iodide FAI, 1.1-1.3 M of PbI2, 0.2 M of methylammonium bromide MABr, 0.2 M of PbBr. Then CsI solution (1.5 M of CsI in DMSO) was added to the prepared precursor, and Cs concentration was varied from 0 to 8%. The prepared precursor solution was used to form perovskite compound Csx(MA0.17FA0.83)(100-x)Pb (I0.83Br0.17)3. The layers were deposited by means of programmable centrifuge. FTO glass with thin TiO2 film was used as a substrate. Thin perovskite layers were annealed for 60 min in an inert atmosphere at 100°C. Optical transmittance measurements of the layers with different cesium concentration were investigated to evaluate their usefulness for fabrication of monolithic perovskite/silicon tandem solar cells. The measured spectra of the perovskite layers are depicted in Fig.1. It is seen that transparency of the layers depends weakly on cesium concentration in the infrared range. All the layers showed transmittance larger than 0.8 at 997 nm wavelength, indicating relatively low optical loss in the spectral region relevant to silicon.