A selenium-based “alkahest”: reactive dissolutions of metals and metal compounds with n-alkylammonium polyselenide solutions

Abstract

The solution-processing of metal chalcogenides offers a promising route to improve the manufacturing of semiconductor devices. The amine–thiol solvent system has been deemed an “alkahest” for its ability to dissolve a wide range of metals and metal chalcogenides. Therefore, it enables convenient synthesis of metal sulfides. However, in the literature there are limited reports of analogous selenium-based “alkahest” chemistry. Here we show that solutions containing n-alkylammonium polyselenides can dissolve a wide range of metals and metal compounds through the formation of soluble metal polyselenides. These metal polyselenides can subsequently be utilized as precursors for the synthesis of a wide range of binary and multinary metal selenide thin films and nanoparticles, including Cu(In,Ga)Se₂, Cu₂ZnSnSe₄, and Ag₂ZnSnSe₄.