Preparation process of copper zinc tin sulfide selenide (CZTSSe) thin film

Abstract

The invention relates to a preparation process of a copper zinc tin sulfide selenide (CZTSSe) thin film. The thin film which is of a single kesterite structure and has high acrystallization degree can be formed under 500 DEG C selenization annealing temperature; the thin film has a low-copper component; with the increase of temperature, the content of the Se element is increased, and finally tends to be stable, and while, the content of the S element is decreased at first and then trends to increase. The preparation process of the invention specifically includes following steps that: (1) some inert gas is added into a reaction container, the reaction container is made to maintain a certain pressure, an then, temperature rise begins; (2) a reaction is carried out for one hour under 280 DEG C, and then, centrifugal washing is carried out, nanoparticles are isolated from a reaction solution, and are dried under an inert environment, and as a result, nanoparticles under two different kinds of conditions can be obtained; and (3) the prepared CZTS nanocrystals are dissolved in a certain amount of hexanethiol, so that a nano slurry solution can be obtained, and a CZTS thin film can be prepared on a soda-lime glass substrate through adopting a dispensing mode, and the CZTS thin film is subjected to selenization annealing treatment, so that the CZTSSe thin film can be obtained.

Description

technical field [0001] The invention relates to a preparation process of a copper-zinc-tin-sulfur-selenium (CZTSSe) thin film. Background technique [0002] As an efficient energy source, solar energy has the characteristics of universal irradiation, huge reserves, and long service life, making it the best choice for future energy sources. In the effective use of solar energy, solar cells made of CZTSSe materials have attracted extensive attention from photovoltaic researchers in various countries due to their high theoretical conversion efficiency, low cost, and strong anti-interference and radiation resistance. [0003] Cu ２ ZnSnS ４ (CZTS) is Ⅰ ２ -II-IV-VI 4 family direct bandgap. Semiconductor materials have two crystal structures of kesterite and stannite. The bandgap width of CZTS material is 1.45ev, which matches the optimal bandgap width required by solar cells, and has a high optical absorption coefficient (α>104 / cm), so it can be used as a P-type absorbing ...

AI Technical Summary

Problems solved by technology

However, there are still problems such as difficult optimization of the composition ratio of the thin film, difficult control of the structure, and low process repeatability. The conversion rate of the solar cells manufactured therefrom is still not ideal, and there is still a lot of room for improvement compared with the theoretical conversion efficiency.

At present, the absorbing layers used in high-efficiency thin-film batteries are almost all prepared by vacuum technology, which requires sophisticated and expensive large-scale equipment, which makes the cost of thin-film solar cells high, and it is difficult to achieve large-scale continuous production.

Since CZTS is composed of a variety of elements, the accuracy of the element ratio is high, and the existence of multi-element lattice, multi-layer interface structure, defects and impurities increases the difficulty of preparation.