SnO 2 Transparent Printing Pastes from Powders for Photon Conversion in SnO 2 ‐Based Dye‐Sensitized Solar Cells

Tin oxide (SnO 2 ) is the most attractive alternative to titanium oxide (TiO 2 ) with the aim of identifying a more positive conduction band material for dye‐sensitized solar cells (DSCs). This study puts forward a protocol based on grinding, sonication, and centrifuge to generate transparent SnO 2 pastes to minimize light reflectance losses from the metal oxide. Under optimized conditions, a highly transparent film with substantially enhanced light penetration depth through active layer SnO 2 is realized for efficient light harvesting from two different commercially available powders (18 and 35 nm nanoparticle sizes). A ruthenium sensitizer ( B11 ) and two organic sensitizers ( NL3 and MK2 ) are shown to achieve higher or comparable photocurrent densities with SnO 2 relative to standard TiO 2 ‐based DSCs. SnO 2 ‐based DSCs show minimum recombination losses, comparable charge collection efficiencies, and minimal photovoltage losses relative to TiO 2 DSCs. Thus, the option of a transparent metal oxide, which can facilitate high photocurrents (>16 mA cm −2 observed) and lower recombination rates than TiO 2 is an attractive material for DSC applications.