Perovskite Solar Cells
Research into organic thin film solar cells shows promise, however, efficiencies need to be improved if they are to be commercially viable. In the past several years Perovskite solar cells, organometal halide materials exhibiting the perovskite structure, have emerged as promising candidates for thin film solar cells.
The perovskite structure is a cubic lattice with the generic formula ABX3, where A is the organic, B is the metal (Pb, or Sn), and X is the halide atom (iodine, bromine, or chlorine). Perovskite halide based solar cells offer an intriguing developmental roadmap that borrows from the condensed matter physics community of perovskite oxide growers. The chemistry of the perovskite can be tuned by doping atoms or molecules onto the A, or B, sites. The structure can be controlled through careful choices of substrates and growth conditions. With these two simple variations, there is tremendous scope for experimentation and fine-tuning of the electronic and optical properties of the materials. With the organometal halide perovskites, we have only just begun to explore the phase space of this class of materials.
RMD is developing light-weight, flexible photovoltaics for military applications and the broader commercial alternative-energy market. We are focusing on photovoltaic cells based on perovskite halide solar cell materials, which have shown remarkable progress in recent years as low-cost solar cell materials that exhibit high efficiencies. Among existing solar cell technologies, perovskite halides present one of the most promising technologies for achieving efficiencies in excess of 20% at lower cost and in a lightweight form factor. RMD has developed flexible perovskite solar cells with efficiencies in excess of 13%.