Effect of interface energy on abnormal grain growth in pyrite films prepared by sol–gel method

The pyrite films were prepared on quartz and glass substrates by the sol–gel dip coating process and sulfuration treatment. The film microstructure, chemical composition and morphology dependent on sulfuration temperature were investigated. The sulfuration treatment at 773–923 K for the films prepared by the sol–gel dip coating process can prepare pyrite films. Some grains show abnormal growth during sulfuration treatment. The grain size of abnormal growth increased to a limited value with increasing the sulfuration temperature. The grain size in pyrite films has bimodal distribution. The first peak is of Lognormal distribution and the second peak Gauss distribution. By determination of the abnormal grain growth activation energy, it can be concluded that the reduction in interface energy at the interface between the substrate and film should be responsible for the grain abnormal growth.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Pyrite films were prepared by sol–gel method and sulfuration treatment. ► The evolution of abnormal grain size and distribution of abnormal grain size were investigated. ► The mechanism of abnormal grain growth was attributed to the interface energy between films and substrates.