Copper-zinc-tin-sulfur quaternary compound, thin film solar cell formed by same, and preparation method thereof

Abstract

The invention discloses a copper-zinc-tin-sulfur quaternary compound, a thin film solar cell formed by the same, and a preparation method thereof. The thin film solar cell comprises a conductive glass / metal gate electrode and a metal backing electrode, and is characterized in that: a p-copper-zinc-tin-sulfur quaternary compound thin film and an n-stannic sulfide thin film which form a p-n structure are arranged between the conductive glass / metal gate electrode and the metal backing electrode. The preparation method for the copper-zinc-tin-sulfur quaternary compound comprises the following steps: mixing copper sulfide, zinc sulfide and stannous sulfide in a mole ratio of 1:0.2-0.8:0.2-0.8; adding the mixture into an appropriate amount of water and performing ball grinding for more than 1 hour; transferring the obtained mixed liquid to a high-pressure autoclave; and performing hydro-thermal treatment for more than 2 hours at the temperature of between 120 and 280 DEG C to obtain copper-zinc-tin-sulfur quaternary compound powder. The thin film solar cell prepared by the invention has the advantages of strong adhesive force, low resistance and rich raw material sources; and the preparation method has the advantages of simple preparation process, low cost and environmental friendliness.

Description

technical field [0001] The invention relates to the field of thin-film solar cells, in particular to a thin-film solar cell and a method for preparing a thin-film solar cell and a copper-zinc-tin-sulfur quaternary compound film constituting the thin-film solar cell, and a method for preparing a p-n junction structure thin-film solar cell. Background technique [0002] Copper-zinc-tin-sulfur quaternary compounds do not contain low-abundance elements Ga, In, Se, and toxic elements Cd, etc., and the band gap is about 1.5eV, which matches the solar spectrum, and the absorption coefficient is as high as 10 4 cm -1 . According to relevant theoretical calculations, single-junction copper-zinc-tin-sulfur quaternary compound thin-film solar cells operate at AM 1.5 and 100mW / cm 2 Under bright light, the photovoltaic performance parameters are: open circuit voltage 1.23V, short circuit current density 29.0mA / cm 2 , fill factor 90.0%, photoelectric conversion efficiency up to 32.2%, ...

AI Technical Summary

Problems solved by technology

Common methods for preparing copper-zinc-tin-sulfur quaternary compound semiconductor films mainly include vapor deposition of metal precursors followed by vulcanization and magnetron sputtering. Japanese patent JP2009135316A uses vapor deposition of metal precursors followed by vulcanization to prepare copper-zinc Tin-sulfur quaternary compound thin films and corresponding n-cadmium sulfide / p-copper zinc tin-sulfur quaternary compound thin-film solar cells have a photoelectric conversion efficiency of 6.9%; Hironori Katagiri et al. (Thin Solid Films, 2007, 515: 5997-5999 ) prepared copper-zinc-tin-sulfur quaternary compound films and thin-film solar cells in the same way, and obtained a photoelectric conversion efficiency of 5.74%; Russian patent RU2347299C1 prepared copper-zinc Tin-sulfur quaternary compound film; Chinese patents CN101026198A and CN101101939A have prepared copper-zinc-tin-sulfur quaternary compound film by melting alloys and magnetron sputtering. The vulcanization process of these preparation methods is complicated and the stoichiometric ratio of the product is difficult to control , The preparation process requires vacuum or gas protection, etc.

Recently, Journal of the American Chemical Society (J.AM.CHEM.SOC.2009, 131, 11672-11673; J.AM.CHEM.SOC.2009, 131, 12554-12555; J.AM.CHEM.SOC.2009, 131 , 12054-12055) reported the use of metal-organic compounds of copper, zinc, and tin in organic solvent oleylamine solution to synthesize copper-zinc-tin-sulfur quaternary compound nanomaterials at 225-300 ° C. These preparation methods are expensive and difficult to obtain in organic solvents. Removal, residual organic matter hinders the improvement of photovoltaic performance of thin-film solar cells