- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
A focus on charge carrier recombination and energy conversion efficiency in nanohybrid photovoltaics
摘要： We investigated the effect of multiwall carbon nanotubes grafted with poly(3-dodecylthiophene) (CNT-graft-PDDT) on the performance of poly(3-hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester photovoltaic cells. It is demonstrated that the presence of small amounts of these modified CNTs improves the structural organization of the films as evidenced by the grazing incidence wide-angle X-ray scattering studies. The ultraviolet–visible (UV–Vis) spectroscopy revealed that the incorporation of CNT-graft-PDDT changes the absorption intensity and induces a redshift to characteristic peaks. CNT hybrid features have appeared on the surface morphology as verified by atomic force microscopic images. The concentration of additive was optimized at 0.5 wt% to obtain the highest efficiency. Doping with this concentration of CNT-graft-PDDT led to 380% power conversion efficiency improvement by enhancement of short-circuit current density (Jsc) from 5.12 to 11.98 mA/cm2, open-circuit voltage (Voc) from 0.6 to 0.66 V, and fill factor from 0.41 to 0.62 in comparison with a reference cell. The photophysics of hybrid systems were also studied by means of the electrochemical impedance spectroscopy as well as Voc and Jsc dependent on the light intensity.
关键词： Organic photovoltaic cells,Charge carrier recombination,Energy conversion,CNT-graft-PDDT
更新于2025-09-23 15:21:01
-
[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Optoelectronic Characterization of Emerging Solar Absorber Cu <sub/>3</sub> AsS <sub/>4</sub>
摘要： Enargite Cu3AsS4 is a promising absorber for thin-film solar cells but little is known about its optoelectronic properties. Here, we present photoluminescence (PL) spectroscopy, time-resolved terahertz spectroscopy (TRTS), time-resolved photoluminescence (TRPL) spectroscopy, and cyclic voltammetry (CV) measurements of enargite thin films. The results indicate promising defect characteristics with minority carrier lifetimes on the order of ns, and band alignments suggest that buffer layers besides CdS must be developed to achieve high efficiency Cu3AsS4 solar cells.
关键词： photovoltaic cells,copper compounds,thin film devices,semiconductor materials,nanocrystals
更新于2025-09-23 15:21:01
-
Light trapping for photovoltaic cells used for optical power transmission
摘要： Photovoltaic (PV) cells used for optical power transmission convert laser light incident from limited directions to electricity. This illumination condition is in contrast to that for solar cells. A combination of an angular selective filter consisting of a dielectric multilayer on the front surface and a diffuse reflector on the rear surface significantly traps both the incident laser light into and radiation from the PV cell. This light trapping effect can improve the monochromatic conversion efficiency of a GaAs PV cell by 9% (absolute) compared with that for the ×4n2 trapping, under 872 nm and 1 W cm?2 laser illumination.
关键词： GaAs,light trapping,conversion efficiency,optical power transmission,photovoltaic cells
更新于2025-09-23 15:21:01
-
Role of Morphology of Surfactant-Free Nanoparticles in Organic Photovoltaics
摘要： Nanoparticulate (NP) ?lms and organic photovoltaic devices have been fabricated from poly(3-hexylthiophene):phenyl C61 butyric acid methyl ester (P3HT:PC61BM) NP aqueous dispersions prepared by the precipitation method. The NP inks were stable for more than 4 days, and nanoparticle organic photovoltaic (NP-OPV) devices with ef?ciency (g) of 1% were fabricated. Detailed analysis of the morphology and performance of the precipitated NP-OPV devices indicated that an optimal blend is responsible for the photocurrent and ef?ciency observed. These results were con?rmed by grazing-incidence x-ray diffraction (GIXRD) analysis, which revealed that the precipitated NPs were resistant to thermal phase segregation, allowing thermal conditioning of the NP ?lms. These results show that precipitated NPs provide a pathway to thermally stable NP-OPV devices with higher photocurrents and ef?ciencies, approaching those of optimal bulk heterojunction (BHJ) OPV devices.
关键词： ink stability,Organic photovoltaic cells (OPV),nanoparticle (NP),nanoparticle morphology,precipitation,surfactant-free
更新于2025-09-23 15:21:01
-
Electrochemical Fingerprint of CuS-Hexagonal Chemistry from (Bis(N-1,4-Phenyl-N-(4-Morpholinedithiocarbamato) Copper(II) Complexes) as Photon Absorber in Quantum-Dot/Dye-Sensitised Solar Cells
摘要： The main deficit of quantum dot/dye-sensitised solar cells (QDSSCs) remains the absence of a photosensitiser that can absorb the entire visible spectrum and increase electrocatalytic activity by enhancing the conversion efficiency of QDSSCs. This placed great emphasis on the synthesis route adopted for the preparation of the sensitiser. Herein, we report the fabrication of hexagonal copper monosulfide (CuS) nanocrystals, both hexadecylamine (HDA) capped and uncapped, through thermal decomposition by thermogravimetric analysis (TGA) and a single-source precursor route. Morphological, structural, and electrochemical instruments were used to assert the properties of both materials. The CuS/HDA photosensitiser demonstrated an appropriate lifetime and electron transfer, while the electron back reaction of CuS lowered the electron lifetime in the QDSSCs. The higher electrocatalytic activity and interfacial resistance observed from current density-voltage (I–V) results agreed with electrochemical impedance spectroscopy (EIS) results for CuS/HDA. The successful fabrication of hexagonal CuS nanostructures of interesting conversion output suggested that both HDA capped and uncapped nanocrystals could be adopted in photovoltaic cells.
关键词： photosensitiser,electrocatalystic,photovoltaic cells,single-source precursor,quantum dots
更新于2025-09-23 15:21:01
-
Selected methods of converting solar energy into electricity - comparative analysis
摘要： This article presents selected methods of converting solar energy into electricity: photovoltaic cells (PV), converters which use photon-enhanced thermionic emission (PETE), and near-field enhanced thermionic energy conversion systems (NETEC). PETE and NETEC systems are innovative solutions that use the thermionic emission phenomenon and can replace photovoltaic generation of electricity. We did a comparative analysis of such issues as: structure, principle of operation, - efficiency. working A comparison of these parameters is shown in the graphs and summarized in the table. Based on the analysis, we have drawn conclusions about previous achievements and development perspectives in the field of converting methods.
关键词： solar energy,PETE,NETEC,conversion efficiency,thermionic emission,photovoltaic cells
更新于2025-09-23 15:21:01
-
[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Dopant Diffusion through Selective Surface Regions to Improve Efficiency in Micro/Nano Textured Thin Solar Cells
摘要： We introduce a simple method to improve efficiency in micro/nano textured solar cells by diffusing a dopant through selective surface regions. This method is effective when the texture size is comparable to or smaller than the characteristic diffusion length. In this size regime, strong inhomogeneity in the dopant concentration often develops in the cells. In our case, the texture is an array of nanopyramidal dips on thin crystalline silicon solar cells. Our simulations for the texture show strong inhomogeneity in the dopant concentration along the textured surface. The strong inhomogeneity creates electrically inactive regions in the texture. With our doping method, our simulations show that the inhomogeneity can be significantly reduced to enhance charge collection efficiency. We confirm this prediction by directly measuring photovoltaic efficiencies of solar cells fabricated with and without using our doping method of selective diffusion. Our experiments demonstrate that our selective dopant diffusion enhances the efficiency from 12.5% to 13.3% for free- standing 15-?m-thick silicon solar cells textured with periodic nanopyramidal dips. Our method would be generally applicable for other micro/nano structures, semiconductor materials, and optoelectronic devices.
关键词： photovoltaic systems,solar power generation,generation,Power engineering and energy,energy,photovoltaic cells
更新于2025-09-23 15:19:57
-
Tuning the hybridization of local exciton and chargea??transfer states in highly efficient organic photovoltaic cells
摘要： Decreasing the energy loss is one of the most feasible ways to improve the efficiencies of organic photovoltaic (OPV) cells. Recent studies have suggested that non-radiative energy loss (ΔEnr) is the dominant factor that hinders further improvements in state-of-the-art OPV cells. However, there is no rational molecular design strategy for OPV materials with suppressed ΔEnr. In this work, taking molecular surface electrostatic potential (ESP) as a quantitative parameter, we establish a general relationship between chemical structure and intermolecular interactions. The results reveal that increasing the ESP difference between donor and acceptor will enhance the intermolecular interaction. In the OPV cells, the enhanced intermolecular interaction will increase the charge transfer (CT) state ratio in its hybridization with local exciton to facilitate the charge generation but simultaneously result in a larger ΔEnr. These results suggest that finely tuning the ESP of OPV materials is a feasible method to further improve the efficiencies of OPV cells.
关键词： hybridization,charge transfer state,intermolecular interaction,organic photovoltaic cells,non-radiative energy loss
更新于2025-09-23 15:19:57
-
Spectral filtering of photovoltaic cells using novel bio-filter: Silver coated Hibiscus extract using methanol solution
摘要： Spectra filtering is a fairly new concept to control the damaging contributions of solar IR radiations to photovoltaic (PV) cells or panel. In this research, the bio-filter was synthesized and tested. The bio-filter was proposed as the panacea to filtering the solar IR radiations. The bio-filter performance was adjudged to show little success, as it was 3% lower than the normal performance in the monocrystalline solar PV panel and 50% higher than the normal performance in the polycrystalline solar PV panel. The varying results in the polycrystalline and monocrystalline PV panels may arise as a result of unequal coating of the panel. Hence, the coating technique is recommended to be uniform and precise in further research work.
关键词： bio-filter,Hibiscus extract,photovoltaic cells,methanol solution,spectral filtering
更新于2025-09-23 15:19:57
-
[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Reciprocal relationship between photoluminescence and photocurrent in two-step photon up-conversion solar cell
摘要： Two-step photon up-conversion solar cell (TPU-SC) we have recently proposed is a single-junction solar cell containing a hetero-interface of different semiconductor materials. Although efficient two-step photon up-conversion is achieved in the TPU-SC, the detailed mechanism of intraband photoexcitation occurring at the hetero-interface is still unclear. In this study, we performed simultaneous measurements of photoluminescence and photocurrent as a function of the applying bias voltage in the TPU-SC. We experimentally demonstrate the reciprocity relationship between the radiative recombination and the photocurrent of the TPU-SC.
关键词： photovoltaic cells,gallium arsenide,quantum dots,heterojunctions,radiative recombination,photoluminescence
更新于2025-09-23 15:19:57