Maykel Courel-Piedrahita
National Polytechnic Institute, Mexico
Title: The role of kesterite materials in the second generation of solar cells
Biography
Biography: Maykel Courel-Piedrahita
Abstract
The most efficient thin film solar cells are based on Cu(In,Ga)(S,Se)2 (CIGSSe) and CdTe compounds known as second generation polycrystalline thin films. The challenge of these materials is to reduce the cost per watt of solar energy conversion, but they are actually formed by expensive and or scanty elements in the earth’s crust such as In, Ga, Te and other that presents toxicity issues like Cd. In the last years, new materials with properties of interest for photovoltaic applications and formed by non-toxic and abundant elements have been suggested as alternatives to the main second generation solar cells based on CdTe and CIGSSe. Semiconductor compounds with kesterite structure (Cu2ZnSn(SxSe1−x)4, Cu2ZnSnS4, Cu2ZnSnSe4), all of them Cadmium-free have been proposed as new candidates for thin film solar cells. However, reported solar cell efficiencies for these compounds have not yet reached the expected values. In fact, solar cell efficiencies lower than 13% have been obtained. In this work, a critical review on the main limiting factors for achieving high efficiency in kesterite thin film solar cells are presented. A discussion about a further solar cell efficiency improvement is also introduced based on theoretical results.