Room-temperature multiple ligands-tailored SnO2 quantum dots endow in situ dual-interface binding for upscaling efficient perovskite photovoltaics with high VOC

Abstract

The benchmark tin oxide (SnO 2 ) electron transporting layers (ETLs) have enabled remarkable progress in planar perovskite solar cell (PSCs). " "However, the energy loss is still a challenge due to the lack of “hidden interface” control. We report a novel ligand-tailored ultrafine SnO 2 quantum dots (QDs) via a facile rapid room temperature synthesis. " "Importantly, the ligand-tailored SnO 2 QDs ETL with multi-functional terminal groups in situ refines the buried interfaces with both the perovskite and transparent electrode via enhanced interface binding and perovskite passivation. " "These novel ETLs induce synergistic effects of physical and chemical interfacial modulation and preferred perovskite crystallization-directing, delivering reduced interface defects, suppressed non-radiative recombination and elongated charge carrier lifetime. " "Power conversion efficiency (PCE) of 23.02% (0.04 cm 2 ) and 21.6% (0.98 cm 2 , V OC loss: 0.336 V) have been achieved for the blade-coated PSCs (1.54 eV E g ) with our new ETLs, representing a record for SnO 2 based blade-coated PSCs. " "Moreover, a substantially enhanced PCE ( V OC ) from 20.4% (1.15 V) to 22.8% (1.24 V, 90 mV higher V OC , 0.04 cm 2 device) in the blade-coated 1.61 eV PSCs system, via replacing the benchmark commercial colloidal SnO 2 with our new ETLs.