All-solid-state quantum-dot-sensitized solar cells with compact PbS quantum-dot thin films and TiO2 nanorod arrays

Abstract

Abstract To improve the electron injection efficiency from PbS quantum dots to TiO 2 nanorods and prevent the direct contact of spiro -OMeTAD and TiO 2 nanorods, a compact PbS quantum-dot thin film can be successfully obtained on TiO 2 nanorod arrays 360 nm in length by repeated spin coating of Pb(Ac) 2 , Na 2 S and 1,2-ethanedithiol solution in a step-by-step process. The corresponding solid-state quantum-dot-sensitized solar cells are fabricated using a novel structured FTO/compact PbS quantum-dot thin film sensitized TiO 2 nanorod array/ spiro -OMeTAD/Au that achieves a photoelectric conversion efficiency of 3.57% under AM 1.5 G illumination (100 mW cm −2 ), which represents a high value among all-solid-state PbS quantum-dot-sensitized TiO 2 nanorod array solar cells.