Perovskite solar cells (PSCs) have been propelled into the limelight over the past decade due to the rapid-growing power conversion efficiency (PCE). However, the internal defects and the interfacial energy level mismatch are detrimental to the device performance and stability. In this study, it is demonstrated that a small amount of indium (In 3+ ) ions in mixed cation and halide perovskites can effectively passivate the defects, improve the energy-level alignment, and reduce the exciton binding energy. Additionally, it is confirmed that In 3+ ions can significantly elevate the initial carrier temperature, slow down the hot-carrier cooling rate, and reduce the heat loss before carrier extraction. The device with 1.5% of incorporated In 3+ achieves a PCE of 22.4% with a negligible hysteresis, which is significantly higher than that of undoped PSCs (20.3%). In addition, the unencapsulated PSCs achieve long-term stability, which retain 85% of the original PCE after 3,000 h of aging in dry air. The obtained results demonstrate and promote the development of practical, highly efficient, and stable hot-carrier-enhanced PSCs.

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To fabricate fine patterns beyond the diffraction limit, a nanostructure photolithography technique is required. In this Letter, we present a method that allows sub-100-nm lines to be patterned photolithographically using ultrahigh-order modes from a symmetrical metal-cladding waveguide (SMCW) in the near field, which are excited by continuous-wave visible light without focusing. The etching depth of the nanopattern reaches more than 200 nm. The localized light intensity distribution can be used to map the photoresist exposure pattern, which agrees well with our theoretical model. This technique opens up the possibility of localizing light fields below the diffraction limit using maskless and lower power visible light.

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