NH2-rich silica nanoparticle as a universal additive in electrolytes for high-efficiency quasi-solid-state dye-sensitized solar cells and quantum dot sensitized solar cells

摘要

In this paper, a novel kind of functional NH2-rich silica nanoparticle (A-SiO2) as an electrolyte additive is reported, which is employed to assemble high-efficiency quasi-solid-state dye-sensitized solar cells (DSCs) and quantum dot sensitized solar cells (QDSCs), while the additional solidifying character of ASiO(2) makes it superior to the common additives. It is found that the A-SiO2 nanoparticle as an additive for ionic-liquid electrolyte can significantly improve the photovoltaic performance of quasi-solid-state DSCs, especially the open-circuit photovoltage (Voc) and fill factor (FF) through ( 1) negatively shifting the TiO2 conduction band (CB) edge, (2) effectively facilitating the ions transport and (3) remarkably inhibiting the charge recombination. Notably, DSC fabricated using the A-SiO2 based ionic-liquid gel electrolytes achieves a power conversion efficiency (PCE) of 7.30% under 1 sun illumination (AM 1.5 G, 100 mW cm(-2)), which is higher than that of DSC with the ionic-liquid electrolyte employing N-methylbenzimidazole (NMBI) and Guanidinium thiocyanate (GuNCS) as additives (PCE = 6.23%). Moreover, the A-SiO2 additive is of the universality in organic electrolytes for DSCs and polysulfide electrolytes for QDSCs. The PCE of CdS/CdSe co-sensitized QDSCs using A- SiO2 additives is improved by 34.9% due to the enhancement of short-circuit current density (Jsc) and Voc, resulting in a champion PCE of 7.11%, which is one of the best results for CdS/CdSe co-sensitized QDSCs. (C) 2018 Published by Elsevier Ltd.