Abstract
The high performance of perovskite solar cells was produced with the help of an electron transport layer (ETL) and hole transport layer. The film ETL (mesoporous (meso)-TiO(2)/carbon dot) boosted the efficiency of the perovskite solar cells. A perovskite cell was fabricated by a coating of carbon dot on a meso-TiO(2) ETL. The fabricated meso-TiO(2)/carbon dot-based device has decreased the pin-holes of the perovskite film layer compared to the meso-TiO(2)-based device, which boosted 3% of the averaged PCE value of the devices. The UV-visible spectroscopy confirmed that the meso-TiO(2)/carbon dot ETL showed better absorbance, that is, absorbed more incident light than meso-TiO(2) ETL to generate higher power conversion efficiency. Coating of carbon dot on meso-TiO(2) reduced carrier recombination, and fadeaway of the perovskite film cracks. The X-ray diffraction spectra displayed the removal of the perovskite component after spin-coating of carbon dot to the meso-TiO(2) ETL, indicating that the suppression of non-radiative recombination improves the device performance compared to meso-TiO(2) ETL. The stability after four weeks on the performance of the device was improved to be 92% by depositing carbon dot on meso-TiO(2) ETL compared to the meso-TiO(2) ETL-based device (82%). Thus, the high-quality perovskite cell was fabricated by coating carbon dot on a meso-TiO(2) ETL, because the electron transport between ETL and perovskite film layer was improved by the injection of electrons from carbon dot.