A novel sodium alginate polysulfide gel electrolyte prepared by grinding method for highly efficient and stable quasi-solid-state quantum dot sensitized solar cells

Abstract

The practical progression of quantum-dot sensitized solar cells (QDSSCs) due to the poor stability, which directly related to the leakage and volatileness of liquid electrolyte. Herein, the sodium alginate (SA) polysulfide gel electrolyte prepared by grinding method was first applied in the quasi-solid state QDSSCs. It has a pore structure which can elevate the rapid diffusion of ions. And the cross-linked interface with photoanode is smooth and non-adherent. The SA polysulfide gel electrolyte was used in Zn-Cu-In-Se (ZCISe) QDSSCs for standard experiments. The QDSSCs are able to materialize the photoelectric conversion efficiency (PCE) of 8.85% (V_oc is 0.63 V, J_sc is 26.16 mA·cm⁻², FF is 51.80), which is 6% higher than the liquid polysulfide QDSSCs (8.34%). Above all, the stability is 3.2 times higher than that of liquid polysulfide electrolyte. The research fulfilled the goal of both efficiency and stability, also environmentally friendly.