Unconventional Route to Oxygen‐Vacancy‐Enabled Highly Efficient Electron Extraction and Transport in Perovskite Solar Cells

Abstract

The ability to effectively transfer photoexcited electrons and holes is an important endeavor towardachieving high-efficiency solar energy conversion. Now,asimple yet robust acid-treatment strategy is used to judiciously create an amorphous TiO 2 buffer layer intimately situated on the anatase TiO 2 surface as an electron-transport layer (ETL) for efficient electron transport. The facile acid treatment is capable of weakening the bonding of zigzag octahedral chains in anatase TiO 2 ,therebyshortening staggered octahedron chains to form an amorphous buffer layer on the anatase TiO 2 surface.S uch amorphous TiO 2 -coated ETL possesses an increased electron density owingt ot he presence of oxygen vacancies,l eading to efficient electron transfer from perovskite to TiO 2 .C ompared to pristine TiO 2 -based devices,the perovskite solar cells (PSCs) with acid-treated TiO 2 ETL exhibit an enhanced short-circuit current and power conversion efficiency.

Enhanced Performance of Planar Perovskite Solar Cells Induced by Van Der Waals Epitaxial Growth of Mixed Perovskite Films on WS2 Flakes

“…X‐ray photoelectron spectroscopy (XPS) was measured to unravel the interaction between the WS 2 flakes and perovskite layer. [ 45 ] Figure 4e,f shows the XPS of Pb 4f and I 3d of perovskite and WS 2 /perovskite mixture and the binding energies (BEs) of perovskite/WS 2 mixture show an obvious shift compared with that of the plain perovskite. The clear shift of BEs indicates the modified chemical environmental of [PbI 6 ] 4− octahedral and the strong S···I interaction.…”

Interface Modulator of Ultrathin Magnesium Oxide for Low‐Temperature‐Processed Inorganic CsPbIBr2 Perovskite Solar Cells with Efficiency Over 11%

“…[63,64] Nevertheless, the increased oxygen vacancies are www.advancedsciencenews.com www.solar-rrl.com harmless to the performance of solar cells. [65,66] On the other hand, the lower binding-energy peak is attributed to the oxygen atoms (O 2þ ), bonded with Sn 2þ and Mg 2þ to form SnO 2 and MgO. Intriguingly, after MgO modified, the both peaks related to O1s shifted to lower binding energy.…”

High-efficiency perovskite solar cells with poly(vinylpyrrolidone)-doped SnO2as an electron transport layer

“…[5][6][7][8][9][10][11][12][13] A significant amount of research effort has focused on controlling the composition and morphology of perovskites, 14 as well as exploring effective and promising materials for hole and electron transport layers (HTLs and ETLs). [15][16][17][18] Comprehensive improvements in each of these areas have led to the increased PCE records. Despite the excellent performance of PSCs, planar PSCs are normally unstable and have severe hysteresis due to ion migration and interface defects in the device.…”