Fig. 1. Schematic diagrams of an all-inorganic CsPbBr₃ PSC with TMDCs interlayer. Schematic diagrams of (a) device structure and (b) energy levels of different layers in the PSC device

Fig. 2. TEM and HRTEM image of TMDCs nanoflakes. (a)-(d) TEM pictures and (e)-(f) HRTEM pictures for (a), (e) MoS₂ nanoflake, (b), (f) MoSe₂ nanoflake, (c), (g) WS₂ nanoflake, (d), (h) WSe₂ nanoflake

Fig. 3. Top-view SEM images of the SnO₂ films with TMDCs modification. Top-view SEM images of the films with different magnifications, (a₁)-(a₃) bare SnO₂, (b₁)-(b₃) SnO₂/MoS₂, (c₁)-(c₃) SnO₂/MoSe₂, (d₁)-(d₃) SnO₂/WS₂ and (e₁)-(e₃) SnO₂/WSe₂

Fig. 4. Transmission curves of FTO/ETL substrates with different TMDCs modification at visible wavelengths

Fig. 5. Schematic diagram and SEM images of CsPbBr₃ perovskite grown on TMDCs. (a) Schematic diagram of CsPbBr₃ perovskite grown on TMDCs; Top-view SEM images of CsPbBr₃ perovskite films grown at the surface of (b) bare SnO₂, (c) SnO₂/MoS₂, (d) SnO₂/MoSe₂, (e) SnO₂/WS₂ and (f) SnO₂/WSe₂

Fig. 6. XRD patterns of the CsPbBr₃ perovskite films grown at different surfaces

Fig. 7. Cross-sectional SEM image of an all-inorganic CsPbBr₃ PSC with TMDCs interlayer

Fig. 8. Photovoltaic performance of the PSCs with and without TMDCs modification. (a) J–V curves and (b) steady power output curves of different devices; (c) J-V curves of the pristine device and the device with WS₂ modification under forward and reverse scan directions; (d) Normalized V_oc, J_sc, PCE and FF stability curves of FTO/SnO₂/WS₂/CsPbBr₃/C device under 25 °C and 80% humidity condition

Fig. 9. Mott-Schottky curves of the PSCs with and without TMDCs modification

Fig. 10. (a) TRPL decay curves and (b) PL curves of perovskite films with and without TMDCs modification