- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Tuning Bandgap of Mixed-Halide Perovskite for Improved Photovoltaic Performance Under Monochromatic-Light Illumination
摘要： Organic–inorganic halide perovskites have emerged as promising materials for optoelectronic devices. This paper focuses on a new application field for perovskite materials as monochromatic-light conversion devices. First the optical properties of organic–inorganic perovskite semiconductors with bandgaps varying from near-infrared to visible at room temperature are presented. Two types of hybrid organic–inorganic mixed-halide perovskites, (FAPbI3)x(MAPbBr3)1-x and FA0.85MA0.15Pb(IxBr1-x)3, are adopted for bandgap tuning, an approximate linear variation of bandgaps with the x value is obtained. The relationship between thin film composition and device performance are investigated. Based on the results of the above bandgap tuning, two kinds of devices with bandgap near the wavelength of 683 nm are characterized under monochromatic-light illumination. A conversion efficiency of up to 40% under 60 mW cm?2 monochromatic-light illumination is achieved. The results confirm that the perovskite films exhibit sharp optical absorption edge, enabling highly efficient monochromatic-light conversion device.
关键词： monochromatic-light,hybrid mixed-halide perovskites,bandgap tuning,photovoltaic performance
更新于2025-11-25 10:30:42
-
Bandgap Tuning of C3N monolayer: A First-Principles Study
摘要： The newly found graphene-like material C3N exhibits great potential in a variety of important applications, due to its unique topological and electronic structures. To extend the utilization, a crucial challenge is to make its intrinsic bandgap (1.03 eV) tunable. Here we performed first-principles calculations to investigate the band structure variations of C3N monolayer under various surface modification treatments, including defect engineering, surface decoration and substitutional doping. Results show that those treatments can induce impurity states, orbital rehybridization, and n- or p-type doping simultaneously, and therefore enable effective band structure adjustment. Importantly, some linear relationships between the bandgap and doping concentration are revealed, paving the way for precise control of C3N bandgap.
关键词： Bandgap tuning,substitutional doping,defect engineering,surface decoration,g-C3N
更新于2025-09-23 15:23:52
-
Semitransparent Perovskite Solar Cells for Smart Windows
摘要： Smart windows, whose transparency can be tuned dynamically and even reversibly changed from transparent to opaque, have been the focus of research since the 1970s [1]. For one thing, smart windows can control the transmission of sunlight into the building, achieving energy savings by balancing the cooling load with the energy requirements of lighting and heating. For another, opaque glass walls act like curtains to protect privacy. The existence of smart windows reduces dependence on manual intervention, and motivates people's lives to become intelligent. The electrochromic windows, whose color can be reversibly changed by applying a small external electric field, have been investigated for use on Boeing 787 Dreamliner airplane [2]. The electrochromic windows are undoubtedly effective, but lack of advantages in inconsistent light-shielding, long-term non-durability and high cost. Thermochromic windows, whose color can be switched by the application of local temperature, have been also investigated. However, such technologies have limitations in impractical high-temperature heating conditions and relatively low light-dark contrast. Besides, the above-mentioned smart windows require external source of energy, thereby failing to achieve the purpose of saving energy. If the photoelectric conversion of solar cells and intelligent control of light transmission are tactfully combined in smart windows, the situation will be changed qualitatively [3]. To date, semitransparent photovoltaics have been proven to be used in power generation windows that provide power output, shading and even heat insulation effect [4, 5], but rarely referring to color switch characteristics. Therefore, it is highly desirable to integrate both functions composed of color-adjustment and power-generation to develop semitransparent photovoltaics as smart windows.
关键词： Semitransparent Perovskite Solar Cells,Light Management,Bandgap Tuning,Device Color,Smart Windows
更新于2025-09-19 17:13:59
-
Segregation-free bromine-doped perovskite solar cells for IoT applications
摘要： Perovskite solar cells have attracted much attention as next-generation solar cells because of their high e?ciency and low fabrication costs. Moreover, perovskite solar cells are a promising candidate for indoor energy harvesting. We investigated the e?ect of bandgap tuning on the characteristics of triple cation-based perovskite solar cells under ?uorescent lamp illumination. According to the current density–voltage curves, perovskite solar cells with a wider bandgap than the conventional one exhibited improved open-circuit voltage without sacri?cing short-circuit current density under ?uorescent lamp illumination. Moreover, the wider bandgap perovskite ?lms including a large amount of bromine in the composition did not show phase segregation, which can degrade the photovoltaic performance of perovskite solar cells, after ?uorescent lamp illumination. Our results demonstrate the facile strategy to improve the performance of perovskite solar cells under ambient lighting and great potential of perovskite solar cells for indoor applications such as power sources for the internet of things.
关键词： indoor energy harvesting,perovskite solar cells,IoT applications,bromine-doped,bandgap tuning
更新于2025-09-16 10:30:52
-
Two-dimensional hydrogenated buckled gallium arsenide: An <i>ab-initio</i> study
摘要： First-principles calculations have been carried out to investigate the stability, structural and electronic properties of two?dimensional hydrogenated GaAs with three possible geometries: chair, zigzag?line and boat con?gurations. The e?ect of van der Waals interactions on 2D H?GaAs systems has also been studied. These con?gurations were found to be energetic and dynamic stable, as well as having a semiconducting character. Although two?dimensional GaAs adsorbed with H tends to form a zigzag?line con?guration, the energy di?erences between chair, zigzag?line and boat are very small which implies the metastability of the system. Chair and boat con?gurations display a Γ?Γ direct bandgap nature, while pristine 2D?GaAs and zigzag?line are indirect semiconductors. The bandgap sizes of all con?gurations are also hydrogen dependent, and wider than that of pristine 2D?GaAs with both PBE and HSE functionals. Even though DFT?vdW interactions increase the adsorption energies and reduce the equilibrium distances of H?GaAs systems, it presents, qualitatively, the same physical results on the stability and electronic properties of our studied systems with PBE functional. According to our results, two?dimensional buckled gallium arsenide is a good candidate to be synthesized by hydrogen surface passivation as its group III?V partners two-dimensional buckled gallium nitride and boron nitride. The hydrogenation of 2D-GaAs tunes the bandgap of pristine 2D-GaAs, which makes it a potential candidate for optoelectronic applications in the blue and violet ranges of the visible electromagnetic spectrum.
关键词： two-dimensional gallium arsenide.,hydrogen,bandgap tuning,Density Functional Theory
更新于2025-09-12 10:27:22