Fabrication of hole-conductor-free perovskite solar cells based on Al doped ZnO and low-cost carbon electrode

Hole-conductor-free perovskite solar cells were fabricated with Al-doped ZnO (AZO) nanostructure as electron transport layer and low-cost commerical carbon paste as counter electrode. In this method perovskite infiltrated into the AZO nanostructure through the carbon electrode which was prepared using doctor blade method. Also because the carbon annealed before deposition of perovskite, perovskite didn’t decompose. The photovoltaic performance of hole-conductor-free perovskite solar cell based on carbon electrode compared with the fabricated cell by Au electrode. The electrochemical impedance spectroscopy, current–voltage analysis, field emission scanning electron microscopy, and X-ray diffraction analysis were carried out to study the effect of counter electrode on the cell performance. The fabricated cell by low cost carbon paste demonstrated higher short circuit current density (J_sc) and power conversion efficiency (8.23%) in compare with fabricated cell by Au electrode (5.45%). Also, the lowest series resistance and highest recombination resistance observed in perovskite solar cell based on Al doped ZnO and carbon electrode.