In a new development, a team of researchers have devised a way to improve the efficiency of all perovskite solar cells using a reducing agent. The technique employed by the group and the performance of the resulting cells is described in the journal Nature Energy.
In a bid to improve the efficiency of solar panels, to make them more competitive with fossil fuels as an energy source, scientists have turned to new raw materials. Perovskite is one of the new raw materials used, a mineral that is mostly made of calcium titanate. Meanwhile, earlier research of stacking perovskite cells on silicon cells show it can increase efficiency, but does not warrants its use.
To address this, more recent research focuses on to replace silicon altogether, and stack two kinds of perovskite cells. The study of perovskite shows it can boost the efficiency of solar cells by 30 percent. Therefore, to make perovskite, engineers have been adding a metal, mostly a lead-tin mixture. However, tin oxidized during fabrication, resulting in degradation and reduced efficiencies.
New method prevents oxidation of Tin
And, with this new effort, researchers have devised a way to prevent oxidation and loss of efficiency. For the method, researchers sought to add something to tin to keep it from oxidizing. A great of search and testing revealed zwitterionic antioxidant inhibiter – commonly known as the reducing agent FSA – to find use to prevent tin from oxidizing.
In the making of lead-perovskite cells, adding zwitterionic antioxidant inhibiter prevented oxidation, and did not interfere with the operation of solar cells in other ways. Thus, without oxidation and degradation of tin, this made it feasible for the creation of all-perovskite solar cells with improved efficiency.