| As a metal sulfide material,CuS has attracted wide attention in many fields such as photoelectric conversion,electronic display,catalysis and energy storage due to its excellent optical,electrical and catalytic properties.Especially when used as a film material,copper sulfide exhibits a broad application prospect in field of electronic display.Researching and developing excellent copper sulfide film materials has significant theoretical and practical significance.In this study,flexible copper sulfide transparent conductive films were prepared in acidic and alkaline environments by a simple chemical bath deposition method using PET as substrates.Scanning electron microscopy and X-ray diffractometer were used to characterize morphology,composition and crystal structure of the sample.Light transmittance and electric conductivity of films were studied by UV-Vis spectrophotometer and four-probe resistance tester.Through film conductivity bending test device,resistance change of film under different curvature radius and flexural resistance of conductive film were analyzed.At the same time,this experiment also used the prepared A4 large-size CuS film as a sample,taking light transmittance and electric conductivity data of different parts as evaluation index,and examining the uniformity of CuS film deposited on the surface of large-sized PET.The results showed that solid state deposits on surface of PET were hexagonal copper sulfide particles in both acidic and alkaline environments,they were all densely packed in form.The only difference between two kinds of morphology was that the former consists of tabular particles and the latter consists of spherical particles.By optimizing main experimental conditions such as type of copper source and sulfur source,molar ratio of copper and sulfur in precursor,type of complexing agent,reaction temperature and time under acidic conditions,the minimum square resistance value of obtained copper sulfide film can reach 20.12 Ω/□,the corresponding light transmittance was 49.9%.By adjusting experimental parameters,a film with excellent electric conductivity and light transmittance can be obtained.At this time,sheet resistance value of the film was 122.40 Ω/□,light transmittance was 82.3%,and the adhesion between copper sulfide film and PET substrate was 3B level.After 250 large-scale bending operations,film can still maintain ideal conductivity.By optimizing experimental conditions such as reaction temperature and time,reactant concentration,complexing agent concentration,drying temperature and time,the minimum sheet resistance of copper sulfide film prepared under alkaline conditions was 81.37 Ω/□,and light transmittance was 59.6%.By adjusting experimental parameters,a CuS film with excellent conductivity and light transmittance could be obtained,the sheet resistance value was 174.20 Ω/□,and light transmittance was 80.2%.The adhesion between CuS film and PET substrate can reach the highest 5B level,and electric conductivity of film can remain stable after 1000 large-scale bending operations.By optimizing and amplifying reaction system in an alkaline environment,an A4 sized CuS film with good uniformity in conductivity and light transmission can be obtained. |
