An Interlayer with Strong Pb-Cl Bond Delivers Ultraviolet-Filter-Free, Efficient, and Photostable Perovskite Solar Cells

Abstract

SummaryThe inorganic metal oxides (IMOs), including titanium dioxide (TiO2) and tin dioxide (SnO2), inevitably induce decomposition of perovskite under UV illumination owing to their photocatalytic activity, and the use of a UV filter will add extra cost and reduce the effective power output. Here, we first reveal that the weak Pb-I bond in I-based perovskite is prone to breakage under UV photocatalysis, leading to serious degradation of the SnO2/perovskite interface. We introduced a chlorine-rich mixed-halide perovskite interlayer (ClMPI), which possesses an excellent tolerance to photocatalysis owing to the strong Pb-Cl bond, between the SnO2 and I-based perovskite. The ClMPI-based device achieves an enhanced efficiency of up to 21.01% (certified 20.17%). Most importantly, the resultant devices can maintain >94% of their initial performance after 180 h under outdoor solar irradiation, >80% after 500 h under UV irradiation, and 500 h under continuous full spectrum illumination at their maximum power points.

2D Cs2PbI2Cl2 Nanosheets for Holistic Passivation of Inorganic CsPbI2Br Perovskite Solar Cells for Improved Efficiency and Stability

“…[59] Second, the Cl-ion doping in the perovskite lattice enhances the structural stability of the perovskite and protects it from degradation induced by the photocatalytic effect of TiO 2 under UV light illumination. [52,58] Furthermore, the thermal stability of the devices was also evaluated. As shown in Figure 5e, the devices were heated at 85 °C for 70 h to test the thermal stability.…”

“…[ 59 ] Second, the Cl‐ion doping in the perovskite lattice enhances the structural stability of the perovskite and protects it from degradation induced by the photocatalytic effect of TiO 2 under UV light illumination. [ 52,58 ]…”

“…According to the literature, the weak PbI bond in perovskite film is prone to breakage under UV light illumination, leading to severe degradation at the ETL/perovskite interface. [ 58 ] Here, we exposed the control and NSs‐modified devices to 365 nm UV light with a high power of 100 mW cm −2 for 200 h (Figure 5d) to investigate their UV light stability. The results show that the PCE of the control device exhibited a sharp drop to 30% of its original value within 200 h. Encouragingly, the DSM devices still retained over 82% of the original PCE.…”

Identifying the functional groups effect on passivating perovskite solar cells

“…The state-of-the-art perovskite solar cell (PSC) has surged to a certified power conversion efficiency (PCE) of more than 25.2% (National Renewable Energy Laboratory https://www.nrel.gov/pv/assets/pdfs/best-researchcell-efficiencies. 20190802.pdf), mainly due to component adjustment, perovskite crystal quality optimization and interface engineering [5][6][7][8]. Recently, improvement of the open-circuit voltage (V OC ) is considered to be an effective approach to further push the efficiency of PSC since the short-circuit current density (J SC ) and fill factor (FF) are quite close to their maximal values [9,10].…”

Room Temperature Processed Double Electron Transport Layers for Efficient Perovskite Solar Cells

“…Organic-inorganic hybrid halide perovskites CH 3 NH 3 PbX 3 (X=I, Br, or Cl) are very promising materials in perovskite solar cells (PSCs) owning to their tunable direct bandgap [ 1 ], high light absorption coefficient [ 2 ], excellent carrier mobility [ 3 ] and long carrier diffusion length [ 4 ]. However, there are a few limitations for the applications of these PSCs [ 5 ].…”