- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Stable Sn/Pb-Based Perovskite Solar Cells with a Coherent 2D/3D Interface
摘要： Low-band-gap metal halide perovskite semiconductor based on mixed Sn/Pb is a key component to realize high-ef?ciency tandem perovskite solar cells. However, the mixed perovskites are unstable in air due to the oxidation of Sn2+. To overcome the stability problem, we introduced N-(3-aminopropyl)-2-pyrrolidinone into the CH3NH3Sn0.5Pb0.5IxCl3-x thin ?lm. The carbonyl group on the molecule interacts with Sn2+/Pb2+ by Lewis acid coordination, forming vertically oriented 2D layered perovskite. The 2D phase is seamlessly connected to the bulk perovskite crystal, with a lattice coherently extending across the two phases. Based on this 2D/3D hybrid structure, we assembled low-band-gap Sn-based perovskite solar cells with power conversion ef?ciency greater than 12%. The best device was among the most stable Sn-based organic-inorganic hybrid perovskite solar cells to date, keeping 90% of its initial performance at ambient condition without encapsulation, and more than 70% under continuous illumination in an N2-?lled glovebox for over 1 month.
关键词： power conversion efficiency,2D/3D interface,stability,Sn/Pb-based,perovskite solar cells
更新于2025-11-21 11:18:25
-
High lying energy of charge-transfer states and small energetic offsets enabled by fluorinated quinoxaline-based alternating polymer and alkyl-thienyl side-chain modified non-fullerene acceptor
摘要： Significant driving forces are the prerequisite to achieve fast and efficient charge separation in fullerene derivatives-based polymer solar cells to achieve high power conversion efficiency (PCE). However, the large driving forces both in photo-induced hole transfer (PHT) and in photo-induced electron transfer (PET) processes lead to significant energy losses, resulting in low open-circuit voltage in the devices. Recent studies indicate the driving forces in non-fullerene acceptors-based devices can be reduced to very low values but still with high PCE and low energy losses. Herein, we report a new donor:acceptor system with high lying energy of charge-transfer excitons (ECT) of 1.50 eV and very small driving forces (PHT of 0.28 eV and PET of 0.11 eV), in which a fluorinated quinoxaline-based alternating polymer (FTQ) and an alkyl-thienyl side-chain modified small molecule (ITIC-Th) are taken as the donor material and non-fullerene acceptor material, respectively. A high power conversion efficiency (PCE) of 8.19% with maximal external quantum efficiency of 71% are achieved successfully in FTQ:ITIC-Th-based device after appropriate thermal annealing treatment, indicating FTQ can be further applied as donor materials with other highly efficient NF-acceptors to achieve enhanced performances and low energy losses.
关键词： Power conversion efficiency,Driving forces,Energy of charge-transfer states,Polymer solar cells
更新于2025-11-14 17:28:48
-
Thinning ferroelectric films for high-efficiency photovoltaics based on the Schottky barrier effect
摘要： Achieving high power conversion efficiencies (PCEs) in ferroelectric photovoltaics (PVs) is a longstanding challenge. Although recently ferroelectric thick films, composite films, and bulk crystals have all been demonstrated to exhibit PCEs >1%, these systems still suffer from severe recombination because of the fundamentally low conductivities of ferroelectrics. Further improvement of PCEs may therefore rely on thickness reduction if the reduced recombination could overcompensate for the loss in light absorption. Here, a PCE of up to 2.49% (under 365-nm ultraviolet illumination) was demonstrated in a 12-nm Pb(Zr0.2Ti0.8)O3 (PZT) ultrathin film. The strategy to realize such a high PCE consists of reducing the film thickness to be comparable with the depletion width, which can simultaneously suppress recombination and lower the series resistance. The basis of our strategy lies in the fact that the PV effect originates from the interfacial Schottky barriers, which is revealed by measuring and modeling the thickness-dependent PV characteristics. In addition, the Schottky barrier parameters (particularly the depletion width) are evaluated by investigating the thickness-dependent ferroelectric, dielectric and conduction properties. Our study therefore provides an effective strategy to obtain high-efficiency ferroelectric PVs and demonstrates the great potential of ferroelectrics for use in ultrathin-film PV devices.
关键词： power conversion efficiency,Schottky barrier effect,ferroelectric photovoltaics,PZT ultrathin film,depletion width
更新于2025-11-14 17:28:48
-
Au@Ag@Ag2S heterogeneous plasmonic nanorods for enhanced dye-sensitized solar cell performance
摘要： Au@Ag@Ag2S heterogeneous nanorods (NRs) with two strong plasmonic absorptive bands were developed for boosting the performance of dye-sensitized solar cells, and the remarkably enhanced plasmonic devices were achieved. By doping different concentrations of the Au@Ag@Ag2S NRs within the TiO2 photoanode layers, various enhanced effects of the plasmonic devices were obtained. With the incorporation of the typical Au@Ag@Ag2S NRs (their aspect ratios: 2.7) into the TiO2 photoanodes, the top efficiency of 6.51% of the fabricated plasmonic photovoltaic devices at their doped concentrations of the 2.31% was observed, exhibiting dramatic 40% enhancement than that of the conventional dye-sensitized solar cells (bare device: 4.65%). Benefiting from effective surface plasmon effects of the Au@Ag@Ag2S NRs, the light-harvesting abilities of photoanodes and dyes in devices are dramatically enhanced, which in return boost the whole performance of photovoltaic devices significantly.
关键词： Dye-sensitized solar cell,Nanorod,Power conversion efficiency,Plasmonic effect
更新于2025-11-14 15:27:09
-
Enabling low voltage losses and high photocurrent in fullerene-free organic photovoltaics
摘要： Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm?2, resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%.
关键词： non-fullerene acceptors,power conversion efficiency,voltage losses,charge separation,organic photovoltaics
更新于2025-11-14 15:18:02
-
Effect of Thionation on the Performance of PNDIT2-Based Polymer Solar Cells
摘要： All-polymer solar cells have gained traction in recent years with solar cell performance of over 11% power conversion efficiency (PCE) recently demonstrated. The n-type polymer PNDIT2, also known as N2200 or P(NDI2OD-T2), has been extensively used for both photovoltaic as well as field-effect transistor applications. When paired with donor materials that have appropriately aligned energy-levels, PNDIT2 has exhibited device efficiencies over 10% PCE, and organic field effect transistors fabricated with PNDIT2 exhibit mobilities over 1 cm2/Vs. Thionation of the NDI moiety, which is the substitution of imide oxygen with sulfur atoms, has been shown to improve the field-effect transistor performance of NDI-based small molecules. Applying this strategy to PNDIT2, we explored the effect that thionation, in a 2S-trans configuration, has on the performance of all-polymer solar cells fabricated with the donor polymer PTB7-Th. Solar cells were fabricated with the original polymer, PNDIT2, as a reference, and an optimized efficiency of 4.85% was achieved. As samples with 100% conversion to 2S-trans configuration could not be produced due to synthetic limitations, batches with increasing ratios of 1S to 2S-trans thionation (15:85, 7:93, and 5:95) were studied. Devices with thionated PNDIT2 exhibited a systematic lowering of photovoltaic parameters with increasing thionation, resulting in device efficiencies of just 0.84%, 0.62%, and 0.42% PCE. The lower performance of the thionated blends is attributed to poor π-π stacking order in the thionated PNDIT2 phase, resulting in lower electron mobilities and finer phase separation. Evidence in support of this conclusion is provided by grazing incidence wide-angle X-ray scattering, transmission electron microscopy, photoluminescence quenching, transient photocurrent analysis, and SCLC measurements.
关键词： π-π stacking,PNDIT2,Thionation,All-polymer solar cells,Power conversion efficiency
更新于2025-10-22 19:40:53
-
Bi-Exciton Dissociation Dynamics in Nano-Hybrid Au-CuInS <sub/>2</sub> Nanocrystals
摘要： Multiexciton harvesting from semiconductor quantum dot has been a new approach for improving the solar cell efficiency in Quantum Dot Sensitized Solar Cells (QDSC). Till date, relation between multiexciton dissociation in metal?semiconductor nanohybrid system and boosting the power conversion efficiency (PCE) of QDSC were never discussed. Herein we report a detailed spectroscopic investigation of biexciton dissociation dynamics in copper indium sulfide (CuInS2, also referred as CIS) and Au-CIS nanohybrid, utilizing both time-resolved PL and ultrafast transient absorption (TA) techniques. Ultrafast transient absorption suggests the formation of bi-exciton in CIS NCs which efficiently dissociates in Au-CIS nanohybrids. Maximum multiexciton dissociation (MED) efficiency is determined to be ~ 80% at higher laser fluency, however it was observed to be 100% at lower laser fluency. Prior to exciton dissociation electrons are captured by Au NP in the nanohybrid from the conduction band of CIS NCs which is energetically higher than Fermi level of Au. Here we demonstrate the proof-of-concept in multi-electron dissociation which may provide a new approach for improving the efficiency in QDSSCs, where we found power conversion efficiency (PCE) of Au-CIS nanohybrids up to 2.49% as compared to ~1.06% ~for pure CIS NCs in similar condition. This finding can be an efficient approach towards the design and development of efficient solar cell and optoelectronic devices using the principles of multiexciton generation and extracting multiexcitons in metal-semiconductor nanohybrid system.
关键词： copper indium sulfide,biexciton dissociation dynamics,Quantum Dot Sensitized Solar Cells,power conversion efficiency,ultrafast transient absorption,Multiexciton harvesting,Au-CIS nanohybrid
更新于2025-09-23 15:21:21
-
Enhancement in the performance of nanostructured CuOa??ZnO solar cells by band alignment
摘要： In this study, we investigated the effect of cobalt doping on band alignment and the performance of nanostructured ZnO/CuO heterojunction solar cells. ZnO nanorods and CuO nanostructures were fabricated by a low-temperature and cost-effective chemical bath deposition technique. The band offsets between Zn1?xCoxO (x = 0, 0.05, 0.10, 0.15, and 0.20) and CuO nanostructures were estimated using X-ray photoelectron spectroscopy and it was observed that the reduction of the conduction band offset with CuO. This also results in an enhancement in the open-circuit voltage. It was demonstrated that an optimal amount of cobalt doping could effectively passivate the ZnO related defects, resulting in a suitable conduction band offset, suppressing interface recombination, and enhancing conductivity and mobility. The capacitance–voltage analysis demonstrated the effectiveness of cobalt doping on enhancing the depletion width and built-in potential. Through impedance spectroscopy analysis, it was shown that recombination resistance increased up to 10% cobalt doping, thus decreased charge recombination at the interface. Further, it was demonstrated that the insertion of a thin layer of molybdenum oxide (MoO3) between the active layer (CuO) and the gold electrode hinders the formation of a Schottky junction and improved charge extraction at the interface. The ZnO/CuO solar cells with 10% cobalt doped ZnO and 20 nm thick MoO3 buffer layer achieved the best power conversion efficiency of 2.11%. Our results demonstrate the crucial role of the band alignment on the performance of the ZnO/CuO heterojunction solar cells and could pave the way for further progress on improving conversion efficiency in oxide-based heterojunction solar cells.
关键词： nanostructured,solar cells,X-ray photoelectron spectroscopy,power conversion efficiency,molybdenum oxide,chemical bath deposition,band alignment,CuO–ZnO,cobalt doping
更新于2025-09-23 15:21:01
-
Development of Combinatorial Pulsed Laser Deposition for Expedited Device Optimization in CdTe/CdS Thin-Film Solar Cells
摘要： A combinatorial pulsed laser deposition system was developed by integrating a computer controlled scanning sample stage in order to rapidly screen processing conditions relevant to CdTe/CdS thin-film solar cells. Using this system, the thickness of the CdTe absorber layer is varied across a single sample from 1.5 ??m to 0.75 ??m. The effects of thickness on CdTe grain morphology, crystal orientation, and cell efficiency were investigated with respect to different postprocessing conditions. It is shown that the thinner CdTe layer of 0.75 ??m obtained the best power conversion efficiency up to 5.3%. The results of this work shows the importance that CdTe grain size/morphology relative to CdTe thickness has on device performance and quantitatively exhibits what those values should be to obtain efficient thin-film CdTe/CdS solar cells fabricated with pulsed laser deposition. Further development of this combinatorial approach could enable high-throughput exploration and optimization of CdTe/CdS solar cells.
关键词： combinatorial pulsed laser deposition,power conversion efficiency,grain morphology,CdTe/CdS thin-film solar cells,device optimization,crystal orientation
更新于2025-09-23 15:21:01
-
Ternary Organic Solar Cells Based on two Non-fullerene Acceptors with Complimentary Absorption and Balanced Crystallinity
摘要： The ternary blend structure has been demonstrated as an effective approach to increase the power conversion efficiency of organic solar cells. An effective approach to enhance the power conversion efficiency of ternary solar cells is based on two non-fullerene acceptors with complimentary absorption range and balanced crystalinity. In this work, by introducing a high crystallinity small-molecule acceptor, named C8IDTT-4Cl with appropriate alkyl side chains into a low crystalline blend of conjugated polymer donor PBDT-TPD and fused-ring electron acceptor ITIC-4F. A ternary device based on the blend PBDT-TPD:ITIC-4F:C8IDTT-4Cl exhibits a best power conversion efficiency of 9.51% with a simultaneous improvement of the short-circuit current density to 18.76 mA cm-2 and the fill factor up to 67.53%. The absorption onset for C8IDTT-4Cl is located at 900 nm, so that the well complementary light absorption is beneficial to the photocurrent. In addition, the existence of high crystallinity C8IDTT-4Cl in the ternary device is found helpful to modulate crystallinity, improve heterojunction morphologies and stacking structure, therefore to realize higher charge mobility and better performance.
关键词： Non-fullerene Acceptors,Ternary Organic Solar Cells,Power Conversion Efficiency,Complimentary Absorption,Balanced Crystallinity
更新于2025-09-23 15:21:01