KAUST scientists have found a way to embed a metal fluoride layer in diverse perovskite-silicon pair sun-based cells that can slow down charge recombination and upgrade execution.
Pair solar power cells that join perovskite and silicon-based subcells in one gadget are supposed to more readily catch and convert daylight into power than their regular single-intersection silicon analogs at a lower cost. Nonetheless, when daylight strikes the perovskite subcell, the subsequent sets of electrons and decidedly charged openings will generally recombine at the connection point between the perovskite and the electron-transport layer. Likewise, a jumble between energy levels at this connection point ruins electron division inside the cell. In total, these issues bring down the greatest working voltage available, or open-circuit voltage, of the pair of cells and cutoff gadget execution.
These exhibition issues can somewhat be tackled by presenting a lithium fluoride layer between the perovskite and the electron-transport layer, which normally contains the electron-acceptor fullerene (C60). Nonetheless, lithium salts promptly liquify and diffuse through surfaces, which makes the gadgets shaky. “None of the gadgets have passed the standard assessment conventions of the International Electrotechnical Commission, provoking us to consider another option,” says lead creator Jiang Liu, a postdoc in Stefaan De Wolf’s group.
“Considering that the greatest efficiency for standard crystalline silicon-based single-junction cells is 26.7 percent, this new method might deliver significant performance enhancements without increasing fabrication costs,”
Lead author Jiang Liu
Liu, De Wolf and colleagues efficiently examined the capability of other metal fluorides, like magnesium fluoride, as interlayer materials at the perovskite/C60 connection point of pair cells. They thermally vanished the metal fluorides on the perovskite layer to frame an ultrathin uniform film with a controlled thickness prior to adding C60 and top contact parts. The interlayers are also extremely straightforward and consistent, as required by the disturbed p-I-n sun-based cell.
The magnesium fluoride interlayer really advanced electron extraction from the perovskite dynamic layer while uprooting C60 from the perovskite surface. This decreased charge recombination at the connection point. It likewise upgraded charge transport across the subcell.
The subsequent pair of sun-based cells accomplished a 50 millivolt expansion in their open-current voltage and an ensured settled power change proficiency of 29.3 percent—one of the greatest efficiencies for perovskite-silicon couple cells, Liu says.
“Taking into account that the best proficiency is 26.7 percent for standard glasslike silicon-based single-intersection cells, this creative innovation could bring extensive execution gains without adding to the expense of manufacture,” Liu says.
To additionally investigate the relevance of this innovation, the group is creating adaptable strategies to deliver modern-scale perovskite-silicon pair cells with regions surpassing 200 square centimeters. “We are likewise fostering a few systems to get profoundly steady-pair gadgets that will pass the basic modern strength conventions,” Liu says.
More information: Jiang Liu et al, Efficient and stable perovskite-silicon tandem solar cells through contact displacement by MgFx, Science (2022). DOI: 10.1126/science.abn8910
Journal information: Science
