Electronic paper from facile, two-step deposition of CuS

A method is proposed to impregnate regular cellulosic paper with semi-conductive particles of copper sulfide. The method consists of a simple two-step procedure: first, metal (Cu) ions in solution are applied to the paper, and second, the aqueous application of a source of sulfide ions, which leads to the spontaneous formation of metal sulfides in the pores of the paper matrix, as evidenced by a color change. This methodology is easy to implement and involves very low-cost and easily available chemical agents, leading to the production of low-price semiconductor devices. In this work, the microscopic morphology and crystalline structures of films were studied, as well as their optical and electrical properties. The proposed sample preparation route could potentially be implemented in further research using different metals in order to obtain tunable physical properties, such as band gap, conductivity and conductivity carrier types.