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1.
Sisi Liu Chongjian Zhang Shuangyuan Li Yong Xia Kang Wang Kao Xiong Haodong Tang Linyuan Lian Xinxing Liu Ming-Yu Li Manlin Tan Liang Gao Guangda Niu Huan Liu Haisheng Song Daoli Zhang Jianbo Gao Xinzheng Lan Kai Wang Xiao Wei Sun Ye Yang Jiang Tang Jianbing Zhang 《Advanced functional materials》2021,31(9):2006864
Lead chalcogenide quantum dot (QD) infrared (IR) solar cells are promising devices for breaking through the theoretical efficiency limit of single-junction solar cells by harvesting the low-energy IR photons that cannot be utilized by common devices. However, the device performance of QD IR photovoltaic is limited by the restrictive relation between open-circuit voltages (VOC) and short circuit current densities (JSC), caused by the contradiction between surface passivation and electronic coupling of QD solids. Here, a strategy is developed to decouple this restriction via epitaxially coating a thin PbS shell over the PbSe QDs (PbSe/PbS QDs) combined with in situ halide passivation. The strong electronic coupling from the PbSe core gives rise to significant carrier delocalization, which guarantees effective carrier transport. Benefited from the protection of PbS shell and in situ halide passivation, excellent trap-state control of QDs is eventually achieved after the ligand exchange. By a fine control of the PbS shell thickness, outstanding IR JSC of 6.38 mA cm−2 and IR VOC of 0.347 V are simultaneously achieved under the 1100 nm-filtered solar illumination, providing a new route to unfreeze the trade-off between VOC and JSC limited by the photoactive layer with a given bandgap. 相似文献
2.
By using a series of polymers in the polymer/PbSe planar heterojunction hybrid solar cells (HSCs), we found that the open circuit voltage of HSCs showed a great improvement compared to that of PbSe Schottky junction solar cells, which might be attributed to the formation of interface dipole, resulting in decreased interfacial resistance, increased built-in electrical field, as well as reduced exciton recombination at interface. Meanwhile, polymers with higher PL quenching have more favorable hole transfer which lead to better device performance. In addition, the energy levels and surface energy of the polymers might largely affect their interaction with PbSe NCs, leading to different interfacial morphologies and influencing the charge transfer efficiency. Furthermore, the optimized HSCs showed a remarkable PCE of 5.31% which was the highest efficiency reported for polymer/PbSe based HSCs. We believe this HSC efficiency can be further improved by selecting polymers with rationally designed structures. 相似文献
3.
Long Hu Robert J. Patterson Yicong Hu Weijian Chen Zhilong Zhang Lin Yuan Zihan Chen Gavin J. Conibeer Gang Wang Shujuan Huang 《Advanced functional materials》2017,27(46)
CdS thin films are a promising electron transport layer in PbS colloidal quantum dot (CQD) photovoltaic devices. Some traditional deposition techniques, such as chemical bath deposition and RF (radio frequency) magnetron sputtering, have been employed to fabricate CdS films and CdS/PbS CQD heterojunction photovoltaic devices. However, their power conversion efficiencies (PCEs) are moderate compared with ZnO/PbS and TiO2/PbS heterojunction CQD solar cells. Here, efficiencies have been improved substantially by employing solution‐processed CdS thin films from a single‐source precursor. The CdS film is deposited by a straightforward spin‐coating and annealing process, which is a simple, low‐cost, and high‐material‐usage fabrication process compared to chemical bath deposition and RF magnetron sputtering. The best CdS/PbS CQD heterojunction solar cell is fabricated using an optimized deposition and air‐annealing process achieved over 8% PCE, demonstrating the great potential of CdS thin films fabricated by the single‐source precursor for PbS CQDs solar cells. 相似文献
4.
研制了应用于下一代高效多结太阳电池中的定电池的 Al0.13GaInP子电池,其实验室效率为10.04%,开路电压为1457.3mV,短路电流为11.9mA。使用量子效率来验证MOVPE生长过程中涉及高Al组分引起的O缺陷对电池性能的影响。相比GaInP单结电池,Al0.13GaInP电池的短路电流下降地较为厉害,实验中生长了GaInP/Al0.13GaInP异质结电池来分析其原因,因此也提出了以牺牲部分开路电压来提升短路电流的一种有效提升电池性能的方法。 相似文献
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An Al0.13GalnP sub-cell used as the top cell in the next generation of high efficiency multi-junction solar cells is fabricated. An efficiency of 10.04% with 1457.3 mV in Voc and 11.9 mA/cm2 in Isc was obtained. QE comparison was carried out to verify the influence of an O-related defect introduced by the high Al-content materials on the cell performance during MOCVD growth. Hetero-structures are employed to confirm the origin of the decreasing short circuit current density compared to a GalnP single junction solar cell. An effective method to improve the performance of broadband solar cells by increasing Isc with a cost of Voc was proposed. 相似文献
7.
Heterojunction and sandwich architectures are two new-type structures with great potential for solar cells. Specifically, the heterojunction structure possesses the advantages of efficient charge separation but suffers from band offset and large interface recombination; the sandwich configuration is favorable for transferring carriers but requires complex fabrication process. Here, we have designed two thin-film polycrystalline solar cells with novel structures:sandwich CIGS and heterojunction perovskite, referring to the advantages of the architectures of sandwich perovskite (standard) and heterojunction CIGS (standard) solar cells, respectively. A reliable simulation software wxAMPS is used to investigate their inherent characteristics with variation of the thickness and doping density of absorber layer. The results reveal that sandwich CIGS solar cell is able to exhibit an optimized efficiency of 20.7%, which is much higher than the standard heterojunction CIGS structure (18.48%). The heterojunction perovskite solar cell can be more efficient employing thick and doped perovskite films (16.9%) than these typically utilizing thin and weak-doping/intrinsic perovskite films (9.6%). This concept of structure modulation proves to be useful and can be applicable for other solar cells. 相似文献
8.
We demonstrate improved performance of inverted planar heterojunction CH3NH3PbI3-xClx perovskite solar cells with a TiO2/MoO3 core/shell nanoparticles (NPs) doped poly(3,4-ethylene dioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) hole-transporting layer (HTL). TiO2/MoO3 Core/shell NPs with size of approximately 40 nm are successfully prepared with a simple wet solution method and are interspersed into PEDOT: PSS layer to construct the HTL. The optimized device shows a high power conversion efficiency of 13.63%, which is dramatically improved compared with the reference device with a pristine PEDOT:PSS HTL. The improvement is mainly attributed to the increased crystalline of the CH3NH3PbI3-xClx film with large-scale domains and a compact morphology. More interesting, the cells exhibit superior stability in ambient conditions, which is attributed to the inhibited penetration of moisture due to the compact morphology of the CH3NH3PbI3-xClx film and the reduced hygroscopicity of the PEDOT:PSS film. 相似文献
9.
Alireza Kargar Sung Joo Kim Paniz Allameh Chulmin Choi Namseok Park Huisu Jeong Yusin Pak Gun Young Jung Xiaoqing Pan Deli Wang Sungho Jin 《Advanced functional materials》2015,25(17):2609-2615
Silicon is one of the promising materials for solar water splitting and hydrogen production; however, it suffers from two key factors, including the large external potential required to drive water splitting reactions at its surface and its instability in the electrolyte. In this study, a successful fabrication of novel p‐Si/n‐SnO2/n‐Fe2O3 core/shell/shell nanowire (css‐NW) arrays, consisting of vertical Si NW cores coated with a thin SnO2 layer and a dense Fe2O3 nanocrystals (NCs) shell, and their application for significantly enhanced solar water reduction in a neutral medium is reported. The p‐Si/n‐SnO2/n‐Fe2O3 css‐NW structure is characterized in detail using scanning, transmission, and scanning transmission electron microscopes. The p‐Si/n‐SnO2/n‐Fe2O3 css‐NWs show considerably improved photocathodic performances, including higher photocurrent and lower photocathodic turn‐on potential, compared to the bare p‐Si NWs or p‐Si/n‐SnO2 core/shell NWs (cs‐NWs), due to increased optical absorption, enhanced charge separation, and improved gas evolution. As a result, photoactivity at 0 V versus reversible hydrogen electrode and a low onset potential in the neutral solution are achieved. Moreover, p‐Si/n‐SnO2/n‐Fe2O3 css‐NWs exhibit long‐term photoelectrochemical stability due to the Fe2O3 NCs shell well protection. These results reveal promising css‐NW photoelectrodes from cost‐effective materials by facile fabrication with simultaneously improved photocathodic performance and stability. 相似文献
10.
利用射频磁控溅射法,在p-Si衬底上生长了Al掺杂的ZnO(AZO)薄膜,并进而制备了AZO/p-Si异质结。X射线衍射仪、紫外-可见光分光光度计、四探针测试仪和霍尔效应测试仪测量表明,AZO薄膜具有良好的结晶质量、光学和电学特性。暗态下的I-V测试表明,AZO/p-Si异质结具有较好的整流特性,反向饱和电流为1.29×10-6A,±2V处的正向和反向电流之比为229.41,计算得出异质结的理想因子为2.28。在标准光照下AZO/p-Si异质结呈现出明显的光生伏特效应,这种异质结太阳电池具有2.51%的光电转换效率。 相似文献
11.
Bingchao Qin Xuegao Hu Yang Zhang Haijun Wu Stephen. J. Pennycook Li‐Dong Zhao 《Advanced Electronic Materials》2019,5(12)
Solid solution alloying is one of the quite powerful approaches to enhance thermoelectric performance because it can simultaneously optimize electrical and thermal transport properties. Herein, a comprehensive investigation on p‐type PbTe‐PbSe‐PbS alloys is reported, in which the carrier concentration is fixed with 2 mol% Na doping. High thermoelectric performance is achieved via synergistically tuning carrier concentration, manipulating electronic band structure, introducing nanostructures, and separating phases. Thus, a high ZT value ≈1.9 is obtained in (PbTe)1−x(PbSe)x alloys, which show both higher Seebeck coefficients and lower lattice thermal conductivities contributed from enlarging band effective mass and scattering phonons, respectively. The obtained results are well confirmed by microstructure characterizations and theoretical calculations based on the single parabolic band (SPB) model and Callaway model. Besides, ZT values ≈1.8 and 1.2 are achieved in (PbTe)1−x(PbS)x and (PbSe)1−x(PbS)x alloys, respectively. Based on the obtained thermoelectric performance from the selected compositions between two or three end‐members (PbTe, PbSe, and PbS), the thermoelectric performance distribution maps for the PbTe‐PbSe‐PbS alloys are established. This comprehensive investigation can provide the performance prediction on any composition within the performance maps of (PbTe)1−x−y(PbSe)x(PbS)y alloys. 相似文献
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《Organic Electronics》2014,15(2):391-398
We present two novel techniques for improving the efficiency of PbS quantum dot (QD) solar cells. First, plasma was applied to QD film with the aim of removing surface organic ligands, and then the chemical and optical properties of the QDs were investigated. Second, a thin layer of conjugated polymer was then deposited on top of the plasma-treated PbS QD film as a transportation layer for holes. The charge separation and subsequent transfer dynamics were examined, as were the resultant photovoltaic characteristics, according to the kind of polymer used. The developed device, which comprises a bilayer heterojunction of plasma-treated PbS QDs and poly[2,6-(4,4′-bis(2-ethylhexyl)dithieno[3,2-b:2′,3′-d]silole)-alt-4,7(2,1,3-benzothiadiazole)] (PSBTBT), showed not only broad-range absorption of the solar spectrum, but also high charge transfer efficiency prior to recombination. This results in a largely increased power conversion efficiency (PCE) of 1.76%, compared to the 0.7% value of a PbS QD-only device not subjected to plasma treatment. This indicates that the proposed techniques are very useful for improving the efficiency of inorganic QD-based solar cells. 相似文献
13.
Songyang Yuan Yeming Xian Yi Long Andreu Cabot Wenzhe Li Jiandong Fan 《Advanced functional materials》2021,31(51):2106233
Inorganic CsPbIxBr3−x perovskite solar cells (PSCs) have gained enormous interest due to their excellent thermal stabilities. However, their intrinsically poor moisture stability hampers their further development. Herein, a chromium-based metal–organic framework group is intercalated inside the inorganic Pb I framework, resulting in a new multiple-dimensional electronically coupled CsPbI2Br perovskite. In this structurally and electronically coupled perovskite, the π-conjugated terpyridyl can delocalize the excited valence electrons of metal Cr3+ ion, enabling multi-interactive charge-carrier transport channels within CsPbI2Br perovskites. The stability and efficiency of the produced devices are substantially enhanced in comparison to their counterparts with only a pristine CsPbI2Br active layer. The optimized all-inorganic PSC yields a power conversion efficiency (PCE) as high as 17.02%. Remarkably, the stabilized device retains 80% of its PCE after 1000 h in the ambient atmosphere. This study provides a new paradigm toward addressing the stability challenge of the inorganic perovskite while enhancing its carrier transport ability. 相似文献
14.
The device performance of photovoltaics with a polymer:fullerene bulk heterojunction (BHJ) structure, consisting of DT-PDPP2T-TT donor polymer and poly(3-hexylthiophene):[6,6]phenyl-C61-butyric acid methyl ester (PC61BM) acceptor compound, was investigated as a function of co-solvent composition. An enhancement of the photocurrent density and fill factor is observed in diodes made by spin-coating with chloroform mixed with ortho-dichlorobenzene, which allows a significantly higher device efficiency of 5.55% compared to diodes made from neat chloroform (efficiency = 3.61%). To clarify the role of the co-solvent, we investigated the nanoscale morphology with AFM, TEM and 2D-GIWAXS techniques and also the free-charge carrier mobility via space-charge limited current theory. We obtained the result that, under such supersaturated conditions, co-solvents induce increased polymer crystalline aggregation into a 3D phase structure and boost charge-carrier transport characteristics. This provides a rational basis for the development of ideally-controlled BHJ films that yield efficient DT-PDPP2T-TT:PCBM solar cells. Therefore, carefully selecting solvent mixtures provides an approach toward efficient low bandgap polymer solar cells. 相似文献
15.
K. v. Maydell E. Conrad M. Schmidt 《Progress in Photovoltaics: Research and Applications》2006,14(4):289-295
We present the optimization and characterization of heterojunction solar cells consisting of an amorphous silicon emitter, a single crystalline absorber and an amorphous silicon rear side which causes the formation of a back surface field (a‐Si:H/c‐Si/a‐Si:H). The solar cells were processed at temperatures <220°C. An optimum of the gas phase doping concentration of the a‐Si:H layers was found. For high gas phase doping concentrations, recombination via defects located at or nearby the interface leads to a decrease in solar cell efficiency. We achieved efficiencies >17% on p‐type c‐Si absorbers and >17·5% on n‐type absorbers. In contrast to the approach of Sanyo, no additional intrinsic a‐Si:H layers between the substrate and the doped a‐Si:H layers were inserted. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
16.
Seong Hyun Lee Myunhun Shin Sun Jin Yun Jung Wook Lim 《Progress in Photovoltaics: Research and Applications》2015,23(11):1642-1648
We showed that thin n‐type CuOx films can be deposited by radio‐frequency magnetron reactive sputtering and demonstrated the fabrication of n‐CuOx/intrinsic hydrogenated amorphous silicon (i‐a‐Si:H) heterojunction solar cells (HSCs) for the first time. A highly n‐doped hydrogenated microcrystalline Si (n‐µc‐Si:H) layer was introduced as a depletion‐assisting layer to further improve the performance of n‐CuOx/i‐a‐Si:H HSCs. An analysis of the external quantum efficiency and energy‐band diagram showed that the thin depletion‐assisting layer helped establish sufficient depletion and increased the built‐in potential in the n‐CuOx layer. The fabricated HSC exhibited a high open‐circuit voltage of 0.715 V and an efficiency of 4.79%. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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We report here synthesis and photovoltaic properties of three merocyanines dyes (DPPT, DTPT, 1-NPPT) which are functionalized with electron withdrawing thiazolidenemalononitrile and electron rich diarylamine functionalities. It is found that structural feature of the diarylamino groups has a profound effect on the physical properties such as the absorption spectrum, oxidation potential, and HOMO/LUMO energy levels. The compound DTPT containing a better electron-donating ditolyl group, exhibits red-shifted absorption with relatively higher molar extinction coefficient, indicating its better light-harvesting ability. Hole mobility of these compounds is found to be strongly dependent on the various intermolecular interactions. Interestingly, single crystal structures reveal that the crystal packing motifs are rather closely related to the observed hole mobility in a trend of DPPT > DTPT > 1-NPPT. Vacuum-processed small-molecule organic solar cells were fabricated using the title merocyanines as p-type materials (donor) in combination with fullerene (C60 or C70) as n-type material (acceptor) with various device configurations. Among them, the DPPT-based devices outperform the devices based on DTPT and 1-NPPT. The power conversion efficiency (PCE) of DPPT-based device was improved from 1.55% of a BHJ device to 2.63% of a PMHJ device and 3.52% of a PMHJ device without the thin donor layer. 相似文献
19.
An attempt is made to understand, quantify, and reduce the reflectance and photocurrent loss in CdTe solar cells. Model calculations are performed to determine the optimum thicknesses of CdS and SnO2 films and anti-reflection (AR) coating on glass that can minimize the reflectance and enhance the performance of CdTe/CdS/SnO2/glass solar cells. Photocurrent loss due to absorption in CdS films is also calculated as a function of CdS thickness. It was found that the current loss due to reflectance ando absorption is more sensitive to the CdS film when its thickness falls below 1500Å. Model calculations show that reducing the CdS thickness from 1500 to 600Å increases short-circuit current density ( Jsc) by 3 mA/cm2 because of reduced reflectance as well as absorption. Further decrease in CdS thickness below 600Å increases reflectance but results in higher Jsc, because current gain due to reduced absorption in thin CdS offsets the current loss due to higher reflectance. Model calculations also indicate that Jsc is not sensitive to SnO2 thickness above 4000Å. Finally, an optimum thickness for single layer MgF2 AR coating on glass was calculated to be 1100Å, which should provide an additional increase of 0.7 mA/cm2 in Jsc. Some of these results are also experimentally validated in this paper. 相似文献
20.
Shanyue Hou Zhu Ma Yanlin Li Zhuowei Du Yi Chen Junbo Yang Wei You Qiang Yang Tangjie Yu Zhangfeng Huang Guomin Li Haoyu Wang Qianyu Liu Guangyuan Yan Haimin Li Yuelong Huang Wenhua Zhang Mojtaba Abdi-Jalebi Zeping Ou Kuan Sun Rong Su Wei Long 《Advanced functional materials》2024,34(4):2310133
Heterojunction perovskite solar cells combine the stability of 2D perovskites and the high efficiency of 3D perovskites, making them an excellent photovoltaic candidate. While heterojunctions with intermixed or gradient perovskites can reduce surface recombination, the aggregation and phase distribution of 2D perovskite induce transport losses, thereby limiting device fill factors. Accordingly, a bulk in situ reconstruction (BISR) strategy is proposed to induce the reconstruction of 3D perovskites on a minim self-assembled 2D crystal seed, forming heterojunction perovskite that runs through the entire active layer. This facilitates charge extraction, relieves tensile stress, and avoids the decomposition of perovskite on grain boundaries. As a result, the best-performing heterojunction perovskite solar cells show a high-power conversion efficiency (PCE) of 24.06% with 82.9% FF for the small-area device (0.105 cm2) and a superior PCE of 19.2% for the large-area module (5 × 5 cm2). Importantly, the unencapsulated device shows dramatically improved operational stability, maintaining 87% of its initial efficiency after 8000 h of storage under ambient atmosphere at room temperature. This work provides an effective and simple approach to establish heterojunction perovskite to simultaneously boost the efficiency and stability of PSCs. 相似文献