Textured HTM-free perovskite/PbS quantum dot solar cell: Optical and electrical efficiency improvement by light trapping control

In recent years, have been seen a leap at the opportunity of investigation tandem solar cells. This due to the complementary bandgap energies of various layers which leads to enhancement of the light absorption and the power conversion efficiency (PCE) of this type of solar cells. In this numerical based study, a new hole transport material (HTM) free perovskite/quantum dot solar cell, exploiting a finite element method (FEM), has been conducted for the first time. The series connection of perovskite (CH3NH3PbI3, 1.55 eV) and colloidal quantum dot (CQD) of lead sulphide (PbS-CQD, 1.3 eV) as light-carrier absorber layers is analysed to achieve the optimal performance with short-circuit current (Jsc) = 25.4 mA/cm2, open-circuit voltage (Voc) = 0.8 V, fill factor (FF) = 0.84. The simulation results illustrate that tandem solar cell yields an overall PCE of 17.2%, exceeding that of 14.53 % of bare perovskite absorbing layer in planar perovskite solar cell (PSC). To enhance the light absorption within the absorber layer and consequently to achieve a higher efficiency, pyramidal texturing of layers, as an effective light-management method was investigated and it reveals that the Jsc and PCE is increased to 29.3 mA/ cm2 and 19.52% respectively. Comparing to the planar perovskite architecture, PCE is improved from 14.53% to 19.52%, indicating a great potential of nanostructure designing in tandem solar cells.