Quantum dot sensitized solar cells

Quantum dot sensitized solar cells (QDSSC) may benefit from the ability to tune the quantum dot optical properties and band gap through the manipulation of their size and composition. Moreover, the inorganic nanocrystals may provide increased stability compared to organic sensitizers. We report the facile fabrication of QDSSC by electrophoretic deposition of CdSe QDs onto conducting electrodes coated with mesoporous TiO(2). Unlike prior chemical linker-based methods, no pretreatment of the TiO(2) was needed, and deposition times as short as 2 h were sufficient for effective coating. Cross-sectional chemical analysis shows that the Cd content is nearly constant across the entire TiO(2) layer. The dependence of the deposition on size was studied and successfully applied to CdSe dots with diameters between 2.5 and 5.5 nm as well as larger CdSe quantum rods. The photovoltaic characteristics of the devices are greatly improved compared with those achieved for cells prepared with a linker approach, reaching efficiencies as high as 1.7%, under 1 sun illumination conditions, after treating the coated electrodes with ZnS. Notably, the absorbed photon to electron conversion efficiencies did not show a clear size-dependence indicating efficient electron injection even for the larger QD sizes. The electrophoretic deposition method can be easily expanded and applied for preparations of QDSSCs using diverse colloidal quantum dot and quantum rod materials for sensitization.

ผลลัพธ์ (แอฟริกา) 1:

Quantum dot sensitief sonselle (QDSSC) kan voordeel trek uit die vermoë om te stem die kwantum dot optiese eienskappe en bandgaping deur die manipulasie van hul grootte en samestelling. Daarbenewens kan die anorganiese kristalle verhoogde stabiliteit in vergelyking met organiese sensitizers. Ons rapporteer die maklike vervaardiging van QDSSC deur elektroforetiese afsetting van CdSe QDs op die uitvoer van elektrodes bedek met mesoporiën TiO (2). Anders voor chemiese-linker-gebaseerde metodes, geen behandeling van die TiO (2) nodig was, en afsetting keer so kort as 2 h was voldoende om effektiewe coating. Deursnee-chemiese ontleding toon dat die CD is amper inhoud konstante oor die hele TiO (2) laag. Die afhanklikheid van die afsetting van die grootte is bestudeer en suksesvol toegepas CdSe kolletjies met diameters tussen 2,5 en 5,5 nm asook groter CdSe kwantum ingesit. Die fotovoltaïese eienskappe van die toestelle is baie verbeter in vergelyking met diegene behaal selle voorberei met 'n linker benadering, bereik doeltreffendheid so hoog as 1,7%, onder 1 son verligting voorwaardes, na die behandeling van die bedekte elektrodes met ZnS. Veral, die geabsorbeer foton omskakeling doeltreffendheid elektronoorgange het nie 'n duidelike grootte-afhanklikheid aandui doeltreffende elektron inspuiting selfs vir die groter QD groottes wys. Die elektroforetiese afsetting metode kan maklik uitgebrei en toegepas vir die voorbereidings van QDSSCs behulp diverse kolloïdale quantum dot en kwantum stok materiaal vir sensitisering.