Van der Waals （vdW） heterojunctions are equipped to avert dangling bonds due to weak, inter-layer vdW force, and ensure strong in-plane covalent bonding for two-dimensional layered structures. We fabricated four het...Van der Waals （vdW） heterojunctions are equipped to avert dangling bonds due to weak, inter-layer vdW force, and ensure strong in-plane covalent bonding for two-dimensional layered structures. We fabricated four heterojunctions devices of different layers based on p-type distorted 1T-MX2 ReSe2 and n-type hexagonal MoS2 nanoflakes, and measured their electronic and optoelectronic properties. The device showed a high rectification coefficient of 500 for the diode, a high ON/OFF ratio and higher electron mobility for the field-effect transistor （FET） compared with the individual components, and a high current responsivity （Rλ） and external quantum efficiency （EQE） of 6.75 A/W and 1,266%, respectively, for the photodetector.展开更多
近年来,全无机铯铅卤素钙钛矿(CsPb X 3,X=Cl,Br,I)量子点由于其色纯度高、具有可调谐的发射波长(410~760 nm)、窄的半峰宽(12~42 nm)和较高的荧光量子产率(最高可达95%以上)以及可全溶液处理等优势而受到人们的高度关注,在显示和照明...近年来,全无机铯铅卤素钙钛矿(CsPb X 3,X=Cl,Br,I)量子点由于其色纯度高、具有可调谐的发射波长(410~760 nm)、窄的半峰宽(12~42 nm)和较高的荧光量子产率(最高可达95%以上)以及可全溶液处理等优势而受到人们的高度关注,在显示和照明领域有着较为广阔的应用前景。本文首先介绍了近年来发展起来的全无机钙钛矿量子点的液相合成方法,如高温热注射法、一步反应法、阴离子交换法和过饱和重结晶法等;其次介绍了全无机钙钛矿量子点的形貌、尺寸和晶型调控及材料组分、反应温度和杂质离子对其发光性能的影响,进而总结了无铅全无机钙钛矿量子点的研究进展;然后介绍了全无机钙钛矿量子点在发光二极管方面的应用进展;最后概述了全无机钙钛矿量子点在未来发展中存在的挑战和机遇。展开更多
低维钙钛矿太阳能电池(Low-Dimensional Perovskite Solar Cells,LD PSCs)是一种稳定性好、疏水性强的新型钙钛矿光伏器件,在新能源领域受到了广泛的关注。本实验以领域内的前沿进展为出发点,提供丁胺(Butylammonium,BA)离子、半胱氨酸...低维钙钛矿太阳能电池(Low-Dimensional Perovskite Solar Cells,LD PSCs)是一种稳定性好、疏水性强的新型钙钛矿光伏器件,在新能源领域受到了广泛的关注。本实验以领域内的前沿进展为出发点,提供丁胺(Butylammonium,BA)离子、半胱氨酸(2-氨基-3-巯基丙酸,Cysteine,Cys)离子作为有机间隔阳离子,合成了低维钙钛矿晶体并制备出以(BA)2(MA)n-1PbnI3n+1或(Cys)2(MA)n-1PbnI3n+1为活性层的钙钛矿太阳能电池,并通过X射线衍射检测、紫外-可见吸收检测等手段对产品进行表征,之后测定了钙钛矿器件的能量转换效率。本实验难度适中,涉及光伏器件的制备与表征,旨在激励本科生对前沿光电研究产生兴趣、培养其科研能力。展开更多
The exploitation of fossil resources to meet humanity’s energy needs is the root cause of the climate warming phenomenon facing the planet. In this context, non-carbon-based energies, such as photovoltaic energy, are...The exploitation of fossil resources to meet humanity’s energy needs is the root cause of the climate warming phenomenon facing the planet. In this context, non-carbon-based energies, such as photovoltaic energy, are identified as crucial solutions. Organic perovskites MAPbI<sub>3</sub> and FAPbI<sub>3</sub>, characterized by their abundance, low cost, and ease of synthesis, are emerging as candidates for study to enhance their competitiveness. It is within this framework that this article presents a comparative analysis of the performances of MAPbI<sub>3</sub> and FAPbI<sub>3</sub> perovskites in the context of photovoltaic devices. The analysis focuses on the optoelectronic characteristics and stability of these high-potential materials. The optical properties of perovskites are rigorously evaluated, including band gaps, photoluminescence, and light absorption, using UV-Vis spectroscopy and photoluminescence techniques. The crystal structure is characterized by X-ray diffraction, while film morphology is examined through scanning electron microscopy. The results reveal significant variations between the two types of perovskites, directly impacting the performance of resulting solar devices. Simultaneously, the stability of perovskites is subjected to a thorough study, exposing the materials to various environmental conditions, highlighting key determinants of their durability. Films of MAPbI<sub>3</sub> and FAPbI<sub>3</sub> demonstrate distinct differences in terms of topography, optical performance, and stability. Research has unveiled that planar perovskite solar cells based on FAPbI<sub>3</sub> offer higher photoelectric conversion efficiency, surpassing their MAPbI<sub>3</sub>-based counterparts in terms of performance. These advancements aim to overcome stability constraints and enhance the long-term durability of perovskites, ultimately aiming for practical application of these materials. This comprehensive comparative analysis provides an enlightened understanding of the optoelectronic performance and展开更多
基金This work was supported by the ＂Hundred Talents Program＂ of Chinese Academy of Sciences （CAS）,the National Natural Science Foundation of China （No. 91233120）, and the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘Van der Waals （vdW） heterojunctions are equipped to avert dangling bonds due to weak, inter-layer vdW force, and ensure strong in-plane covalent bonding for two-dimensional layered structures. We fabricated four heterojunctions devices of different layers based on p-type distorted 1T-MX2 ReSe2 and n-type hexagonal MoS2 nanoflakes, and measured their electronic and optoelectronic properties. The device showed a high rectification coefficient of 500 for the diode, a high ON/OFF ratio and higher electron mobility for the field-effect transistor （FET） compared with the individual components, and a high current responsivity （Rλ） and external quantum efficiency （EQE） of 6.75 A/W and 1,266%, respectively, for the photodetector.
文摘近年来,全无机铯铅卤素钙钛矿(CsPb X 3,X=Cl,Br,I)量子点由于其色纯度高、具有可调谐的发射波长(410~760 nm)、窄的半峰宽(12~42 nm)和较高的荧光量子产率(最高可达95%以上)以及可全溶液处理等优势而受到人们的高度关注,在显示和照明领域有着较为广阔的应用前景。本文首先介绍了近年来发展起来的全无机钙钛矿量子点的液相合成方法,如高温热注射法、一步反应法、阴离子交换法和过饱和重结晶法等;其次介绍了全无机钙钛矿量子点的形貌、尺寸和晶型调控及材料组分、反应温度和杂质离子对其发光性能的影响,进而总结了无铅全无机钙钛矿量子点的研究进展;然后介绍了全无机钙钛矿量子点在发光二极管方面的应用进展;最后概述了全无机钙钛矿量子点在未来发展中存在的挑战和机遇。
文摘低维钙钛矿太阳能电池(Low-Dimensional Perovskite Solar Cells,LD PSCs)是一种稳定性好、疏水性强的新型钙钛矿光伏器件,在新能源领域受到了广泛的关注。本实验以领域内的前沿进展为出发点,提供丁胺(Butylammonium,BA)离子、半胱氨酸(2-氨基-3-巯基丙酸,Cysteine,Cys)离子作为有机间隔阳离子,合成了低维钙钛矿晶体并制备出以(BA)2(MA)n-1PbnI3n+1或(Cys)2(MA)n-1PbnI3n+1为活性层的钙钛矿太阳能电池,并通过X射线衍射检测、紫外-可见吸收检测等手段对产品进行表征,之后测定了钙钛矿器件的能量转换效率。本实验难度适中,涉及光伏器件的制备与表征,旨在激励本科生对前沿光电研究产生兴趣、培养其科研能力。
文摘The exploitation of fossil resources to meet humanity’s energy needs is the root cause of the climate warming phenomenon facing the planet. In this context, non-carbon-based energies, such as photovoltaic energy, are identified as crucial solutions. Organic perovskites MAPbI<sub>3</sub> and FAPbI<sub>3</sub>, characterized by their abundance, low cost, and ease of synthesis, are emerging as candidates for study to enhance their competitiveness. It is within this framework that this article presents a comparative analysis of the performances of MAPbI<sub>3</sub> and FAPbI<sub>3</sub> perovskites in the context of photovoltaic devices. The analysis focuses on the optoelectronic characteristics and stability of these high-potential materials. The optical properties of perovskites are rigorously evaluated, including band gaps, photoluminescence, and light absorption, using UV-Vis spectroscopy and photoluminescence techniques. The crystal structure is characterized by X-ray diffraction, while film morphology is examined through scanning electron microscopy. The results reveal significant variations between the two types of perovskites, directly impacting the performance of resulting solar devices. Simultaneously, the stability of perovskites is subjected to a thorough study, exposing the materials to various environmental conditions, highlighting key determinants of their durability. Films of MAPbI<sub>3</sub> and FAPbI<sub>3</sub> demonstrate distinct differences in terms of topography, optical performance, and stability. Research has unveiled that planar perovskite solar cells based on FAPbI<sub>3</sub> offer higher photoelectric conversion efficiency, surpassing their MAPbI<sub>3</sub>-based counterparts in terms of performance. These advancements aim to overcome stability constraints and enhance the long-term durability of perovskites, ultimately aiming for practical application of these materials. This comprehensive comparative analysis provides an enlightened understanding of the optoelectronic performance and
