This talk describes projects in our group to develop thin-film photovoltaics based on earth-abundant iron pyrite (FeS2) active layers and PbSe quantum dot (QD) solids. I will first introduce the promise and challenge of pyrite, describe solution- and gas-phase syntheses of pyrite films, and present preliminary electrical characterization of pyrite layers and device stacks. Then I will switch gears to highlight several projects focused on the chemistry/physics of QD solids, including our use of atomic layer deposition to produce environmentally-robust PbSe QD films with long carrier diffusion lengths for next-generation solar cells.