A Cadmium-Free Cu₂ZnSnS₄/ZnO Hetrojunction Solar Cell Prepared by Practicable Processes

Abstract

A Cadmium-free Cu 2 ZnSnS 4 /ZnO hetrojunction solar cell with conversion efficiency of 4.29% has been obtained. The Cu 2 ZnSnS 4 absorber film was formed utilizing sulfurization of laminated metallic precursors, and the ZnO buffer layer was then deposited on it by ultrasonic spray pyrolysis. In comparison with a conventional Cu 2 ZnSnS 4 /CdS hetrojunction solar cell, the open circuit voltage as well as the relative quantum efficiency at the short-wavelength regions was increased. The in-plane homogeneity of p-n junction was improved by depositing the ZnO layer on Cu 2 ZnSnS 4 film via ultrasonic spray pyrolysis.

Progress in Ultrasonic Spray Pyrolysis for Condensed Matter Sciences Developed From Ultrasonic Nebulization Theories Since Michael Faraday

“…Another interesting case of one dimensional growth by USP was observed by Htay et al [242,254,317,367,477] who reported micro-sized platelets, wires and tips of ZnO obtained at controlled conditions. Temperature of synthesis was found to dictate the morphology of the micro and submicronstructures that they obtained.…”

Influence of Ge composition in the Cu2Sn1−Ge S3 thin-film photovoltaic absorber prepared by sulfurization of laminated metallic precursor

“…Two types of precursors having a total thickness of 500 nm with different laminated layers (six and nine layers) were used in the experiments for investigating the influence of precursor structure. The details of the preparation of precursors and the sulfurization technique were reported previously [35,36]. Effects on the material properties due to the difference in the final Ge composition were investigated by utilizing analyses such as a scanning electron microscopy (FE-SEM, Hitachi, S-4100), an electron probe microanalysis (EPMA; Shimadzu EPMA-1610), an X-ray diffractometry (XRD, Rigaku, RINT-2200V/PCSV, Cu Kα ray; λ = 1.5418 Å with a Bragg-Brentano θ − 2θ geometry at 40 kV, 30 mA), a laser Raman spectrometry (COMET-3504, an excitation source of λ = 532 nm, a 1800 line mm −1 grating), an optical transmittance measurement (Spectrophotometer, Shimadzu UV-3100), a heat-probe conductivity measurement, and a four-probe resistivity measurement (Kyowa Riken, K89PS, tips gap: 1 mm).…”

Temperature-dependent Raman spectroscopy of Cu2Sn1− x Ge x S3 thin films

“…The details of thin films preparation process and sulfurization technique were reported elsewhere. 5,34,35) The actual chemical compositions of the samples utilized in this experiment were described in Table I. An XDR (Rigaku RINT-2200V=PCSV, Cu Kα ray, λ = 1.5418 Å with a Bragg-Brentano θ-2θ geometry at 40 kV, 30 mA) was used to identify the crystalline quality of the thin films.…”