Enhanced Photovoltaic Performance of Quasi-Solid Dye-Sensitized Solar Cells Based on Composite Gel Electrolyte with Intercalated Mg-Al Layered Double Hydroxide

Mg-Al layered double hydroxide (LDH), a two-dimensional layered material, has been added in composite gel electrolyte for quasi-solid dye-sensitized solar cells (DSSCs), resulting in enhanced power conversion efficiency (PCE) from 0.69% to 2.05%. Herein, we demonstrated that using stearic acid-intercalated LDH (LDH-St) as additives instead of pristine LDH in composite gel electrolyte achieved even higher PCE of 2.86%. XRD analysis revealed that the interlayer spacing of LDH-St has been enlarged from 0.77 nm to 4.41 nm, which is highly favorable for iodide/triiodide ions transportation. The enhancement in photovoltaic performance was primarily explained by a decrease of charge transfer resistance (Rct), an increase of limiting current density (jlim) and the suppressed dark current density for electrolyte containing LDH-St compared with that containing LDH.