Bandgap Engineering Enhances the Performance of Mixed‐Cation Perovskite Materials for Indoor Photovoltaic Applications

Abstract

Indoor photovoltaics (IPVs) are attracting renewed interest because they can provide sustainable energy through the recycling of photon energy from household lighting facilities. Herein, the Shockley–Queisser model is used to calculate the upper limits of the power conversion efficiencies (PCEs) of perovskite solar cells (PeSCs) for two types of artificial light sources: fluorescent tubes (FTs) and white light–emitting diodes (WLEDs). An unusual zone is found in which the dependence of the PCEs on the bandgap (Eg) under illumination from the indoor lighting sources follows trends different from that under solar irradiation. In other words, IPVs exhibiting high performance under solar irradiation may not perform well under indoor lighting conditions. Furthermore, the ideal bandgap energy for harvesting photonic power from these indoor lighting sources is ≈1.9 eV—a value higher than that of common perovskite materials (e.g., for CH3NH3PbI3). Accordingly, Br− ions are added into the perovskite films to increase their values of Eg. A resulting PeSC featuring a wider bandgap exhibits PCEs of 25.94% and 25.12% under illumination from an FT and a WLED, respectively. Additionally, large‐area (4 cm2) devices are prepared for which the PCE reaches ≈18% under indoor lighting conditions.

Position Effects of Metal Nanoparticles on the Performance of Perovskite Light-Emitting Diodes

“…Figure 5 b shows the corresponding time-resolved PL (TRPL) decay profiles for the PeLEDs prepared under various conditions. The curves could be fitted well using a biexponential decay equation [ 27 , 28 ]. The fast decay (τ 1 ) could be assigned to the surface recombination, while the slower decay (τ 2 ) represents radiative recombination [ 27 ].…”

Indoor photovoltaics, The Next Big Trend in solution‐processed solar cells

“…The adjusting stoichiometric ratio of halide ions or using triple cations may bring about the possibility of better PSC performance as a result of a closer bandgap to 1.9 eV. Accordingly, Br − ions were added into the PSCs to increase their bandgap values by Wu et al They demonstrated the bandgap of MA 0.85 Cs 0.15 Pb(I 0.85 Br 0.15 ) 3 can be enlarged to 1.66 eV, which resulted in the highest PCEs of 25.94% and 25.12% under illumination from fluorescent tubes and a white LED 76 . Similarly, Cheng et al reported a triple‐anion CH 3 NH 3 PbI 2−x BrCl x PSCs with a specially tailored bandgap.…”

Emerging Organic/Hybrid Photovoltaic Cells for Indoor Applications: Recent Advances and Perspectives

“…Wu et al reported that the perovskite bandgap increased with the addition of Br − ions into common perovskite materials, achieving an bandgap energy of 1.66 eV for efficiently harvesting photonic power from the indoor lighting sources. [ 70 ] In addition, Choi et al identified that Cs + cations can significantly improve the stability and efficiency of PSCs. [ 71 ] Therefore, the addition of Br − ions to mixed cationic perovskites is an effective approach for improving the bandgap and device performance.…”