Exploring Different Designs in Thieno[3,4-b]pyrazine-Based Dyes to Enhance Divergent Optical Properties in Dye-Sensitized Solar Cells

Two novel organic sensitizers for Dye-Sensitized Solar Cells (DSSC), called TP1 and TP2, based on the electron-poor thieno[3,4-b]pyrazine (TPz) π-bridge electron-rich N,N-bis(4-(hexylthio)phenyl)aniline (TPA) were designed following two different approaches: classical D-A-π-A design a symmetric structure with double anchoring functions. Both compounds prepared exploiting short synthetic pathways direct arylation strategies possibly one-pot desymmetrization. The dyes displayed opposite optical properties: broad intense light absorption over entire visible spectrum TP1, localized that peaked in center of region resulting pitch-dark coloration green tone, respectively. When assembling photovoltaic devices, electrolyte compositions explored to enhance properties dyes. Power conversion efficiencies as high 5.2% under full sun intensity recorded small test devices. composition transmitted through TP2-containing transparent DSSC fits well human eye sensitivity spectrum, thus fulfilling transparency requirements building-integrated photovoltaics (BIPV).