Perovskite solar cells(PSCs) are the most promising commercial photoelectric conversion technology in the future.The planar p–i–n structure cells have advantages in negligible hysteresis, low temperature preparation...Perovskite solar cells(PSCs) are the most promising commercial photoelectric conversion technology in the future.The planar p–i–n structure cells have advantages in negligible hysteresis, low temperature preparation and excellent stability.However, for inverted planar PSCs, the non-radiative recombination at the interface is an important reason that impedes the charge transfer and improvement of power conversion efficiency. Having a homogeneous, compact, and energy-levelmatched charge transport layer is the key to reducing non-radiative recombination. In our study, NiO_(x)/Sr:NiO_(x)bilayer hole transport layer(HTL) improves the holes transmission of NiO_(x)based HTL, reduces the recombination in the interface between perovskite and HTL layer and improves the device performance. The bilayer HTL enhances the hole transfer by forming a driving force of an electric field and further improves J_(sc). As a result, the device has a power conversion efficiency of 18.44%, a short circuit current density of 22.81 m A·cm^(-2) and a fill factor of 0.80. Compared to the pristine PSCs, there are certain improvements of optical parameters. This method provides a new idea for the future design of novel hole transport layers and the development of high-performance solar cells.展开更多
Broadband electroluminescence based on environment-friendly emitters is promising for healthy lighting yet remains an unprecedented challenge to progress.The copper halide-based emitters are competitive candidates for...Broadband electroluminescence based on environment-friendly emitters is promising for healthy lighting yet remains an unprecedented challenge to progress.The copper halide-based emitters are competitive candidates for broadband emission,but their high-performance electroluminescence shows inadequate broad emission bandwidth of less than 90 nm.Here,we demonstrate efficient ultra-broadband electroluminescence from a copper halide(CuI)nanocluster single emitter prepared by a one-step solution synthesis-deposition process,through dedicated design of ligands and subtle selection of solvents.The CuI nanocluster exhibits high rigidity in the excitation state as well as dual-emissive modes of phosphorescence and temperature-activated delayed fluorescence,enabling the uniform cluster-composed film to show excellent stability and high photoluminescent efficiency.In consequence,ultra-broadband light-emitting diodes(LEDs)present nearly identical performance in an inert or air atmosphere without encapsulation and outstanding high-temperature operation performance,reaching an emission full width at half maximum(FWHM)of~120 nm,a peak external quantum efficiency of 13%,a record maximum luminance of~50,000 cd m^(−2),and an operating half-lifetime of 137 h at 100 cd m^(−2).The results highlight the potential of copper halide nanoclusters for next-generation healthy lighting.展开更多
基金supported by the Fundamental Research Funds for the Central Universities, China (Grant No. 2021QN1110)。
文摘Perovskite solar cells(PSCs) are the most promising commercial photoelectric conversion technology in the future.The planar p–i–n structure cells have advantages in negligible hysteresis, low temperature preparation and excellent stability.However, for inverted planar PSCs, the non-radiative recombination at the interface is an important reason that impedes the charge transfer and improvement of power conversion efficiency. Having a homogeneous, compact, and energy-levelmatched charge transport layer is the key to reducing non-radiative recombination. In our study, NiO_(x)/Sr:NiO_(x)bilayer hole transport layer(HTL) improves the holes transmission of NiO_(x)based HTL, reduces the recombination in the interface between perovskite and HTL layer and improves the device performance. The bilayer HTL enhances the hole transfer by forming a driving force of an electric field and further improves J_(sc). As a result, the device has a power conversion efficiency of 18.44%, a short circuit current density of 22.81 m A·cm^(-2) and a fill factor of 0.80. Compared to the pristine PSCs, there are certain improvements of optical parameters. This method provides a new idea for the future design of novel hole transport layers and the development of high-performance solar cells.
文摘Broadband electroluminescence based on environment-friendly emitters is promising for healthy lighting yet remains an unprecedented challenge to progress.The copper halide-based emitters are competitive candidates for broadband emission,but their high-performance electroluminescence shows inadequate broad emission bandwidth of less than 90 nm.Here,we demonstrate efficient ultra-broadband electroluminescence from a copper halide(CuI)nanocluster single emitter prepared by a one-step solution synthesis-deposition process,through dedicated design of ligands and subtle selection of solvents.The CuI nanocluster exhibits high rigidity in the excitation state as well as dual-emissive modes of phosphorescence and temperature-activated delayed fluorescence,enabling the uniform cluster-composed film to show excellent stability and high photoluminescent efficiency.In consequence,ultra-broadband light-emitting diodes(LEDs)present nearly identical performance in an inert or air atmosphere without encapsulation and outstanding high-temperature operation performance,reaching an emission full width at half maximum(FWHM)of~120 nm,a peak external quantum efficiency of 13%,a record maximum luminance of~50,000 cd m^(−2),and an operating half-lifetime of 137 h at 100 cd m^(−2).The results highlight the potential of copper halide nanoclusters for next-generation healthy lighting.
