Toward ‘greener,’ inexpensive solar cells

Solar panels are proliferating across the globe to help reduce the world’s dependency on fossil fuels. But conventional panels are not without environmental costs, too. Now scientists report a new advance toward more practical, “greener” solar cells made with inexpensive halide perovskite materials. They have developed low-bandgap perovskite solar cells with a reduced lead content and a power conversion efficiency of 15 percent.