INVESTIGADORES
BUDINI nicolas
congresos y reuniones científicas
Título:
Electrical characterization of lead halide perovskites for photovoltaic applications
Autor/es:
J. CARAM; N. BUDINI; R. D. ARCE
Lugar:
Gramado
Reunión:
Encuentro; XVI SBPMat; 2017
Resumen:
Over the last few years, a new research line on solar cells based on hybridorganic-inorganic perovskites arose. These cells showed an unprecedentedincrease in their power conversion efficiency (PCE), from 3.8% [1] to 22% [2] over a period of 8 years. Methylammonium lead halide perovskites (such asCH3NH3PbX3, with X=Cl, Br, I) possess a great potential to improve the PCE dueto remarkable properties: high absorption coefficients, large diffusion lengths and long charge carriers lifetime. In addition, the low-temperatures required for the solution-processing method make these materials suitable for fabricating low-cost optoelectronic devices. Currently, the highest PCE are being obtained from PbI2/CH3NH3I or PbCl2/CH3NH3I precursor solutions, using gamma-butirolactone or dimethylformamide as solvents [3,4]. The films are deposited by spin-coating and then annealed at 100 °C under N2 atmosphere. In this work, we studied isolated perovskite films, deposited over glass substrates. We deposited several samples with different parameters, such as concentrations of the precursor solutions, annealing temperature and humidity. Another parameter that was considered, which is relevant for perovskite deposition onto glass, was the substrate cleaning. The samples were characterized by conventional optical microscopy, X-ray diffraction and transmittance measurements in the UV-visible range. Conductivity and photoconductivity measurements were also performed in thick samples due to experimental issues regarding the deposition of continuous thin films on glass. We discuss transport mechanisms and analyze the influence of the mentioned fabrication parameters on the resulting film quality.References:1. Kojima et al, J. Am. Chem. Soc. 2009, 131, 6050−6051.2. De Angelis et al, ACS Energy Lett., pp. 857?861, 2017.3. Seo et al, A. Chem. Res., Vol. 49-3 (2016)p. 562?572.4. Zuo et al, Adv. Sc., DOI: 10.1002/advs.201500324, 2016.