[en] Highlights: • CH₃NH₃PbI₃-PCBM Bulk heterojunction hybrid films were grown on c-TiO₂ thin films. • The hybrid films exhibited very large crystalline grains of 2–3 μm. • There was ∼36.9% enhancement in the PCE of bulk-heterojunction solar cells. • Passivation in hysteresis has been also observed in devices with CH₃NH₃PbI₃-PCBM. We report here the impact of CH₃NH₃PbI₃-PCBM bulk heterojunction (BHJ) active layer on the photovoltaic performance of perovskite solar cells. The solar cells were prepared in normal architecture on FTO coated glass substrates with compact TiO₂ (c-TiO₂) layer on FTO as electron transport layer (ETL) and poly(3-hexylthiophene) (P3HT) as hole transport layer (HTL). For comparison, a few solar cells were also prepared in planar heterojunction structure using CH₃NH₃PbI₃ only as the active layer. The bulk heterojunction CH₃NH₃PbI₃-PCBM active layer exhibited very large crystalline grains of 2–3 μm compared to ∼150 nm only in CH₃NH₃PbI₃ active layer. Larger grains in bulk-heterojunction solar cells resulted in enhanced power conversion efficiency (PCE) through enhancement in all the photovoltaic parameters compared to planar heterojunction solar cells. The bulk-heterojunction solar cells exhibited ∼9.25% PCE with short circuit current density (Jsc) of ∼18.649 mA/cm², open circuit voltage (Voc) of 0.894 V and Fill Factor (FF) of 0.554. There was ∼36.9% enhancement in the PCE of bulk-heterojunction solar cells compared to that of planar heterojunction solar cells. The larger grains are formed as a result of incorporation on PCBM in the active layer.