In this study, P3HT:PCBM organic photovoltaic (OPV) devices, with or without ZnO nanoparticles buffer layer between the photoactive layer (P3HT:PCBM) and the cathode (Al top electrode), were fabricated. The devices were annealed at 145 °C either before or after depositing the top electrode. The objective of this study was to investigate the effects of the ZnO buffer layer and pre-/post-fabrication annealing on the general performance of these devices. The short-circuit current density (JSC), open-circuit voltage (VOC) and the external quantum efficiency (EQE) of the OPV devices were improved by the insertion of the ZnO layer and post-fabrication annealing. The post-fabrication annealed devices, with or without the ZnO layer, exhibited higher values of JSC, VOC and EQE than those of similar devices annealed before depositing the Al metal. This can be attributed to, among other things, improved charge transport across the interface between the photoactive layer and the Al top electrode as a result of post-annealing induced modification of the interface morphology. 相似文献
Poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) films were fabricated using an electrospray deposition (ESD) method. The ESD PEDOT:PSS films exhibited higher PSS content on the surface than spin-coated PEDOT:PSS films, which results in a higher work function. Based on this result, metal-electrode-free inverted organic photovoltaics (OPVs) were fabricated. The ESD PEDOT:PSS was used as the top electrode on the poly(3-hexythiophene-2,5-diyl) (P3HT):[6,6]-phenyl C61 butyric acid methyl ester (PCBM) light-absorbing layer. The power conversion efficiency (PCE) of OPVs was significantly increased with the 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile layer. The improved PCE would be attributed to the suppression of exciton quenching at the P3HT:PCBM and PEDOT:PSS interface. 相似文献
In an effort to develop hybrid organic solar cells with improved power conversion efficiency (PCE), devices based on poly (3-hexylthiophene) (P3HT):phenyl C61-butyric acid methyl ester (PCBM) active layer and poly (3,4-ethylenedioxythiophene) (PEDOT):poly (styrenesulfonate) (PSS) buffer layers were prepared. A systematic replacement of PCBM was achieved by introducing nanostructured TiO2 (∼15 nm particle size), dissolved separately in chlorobenzene (CB) and 1,2 –dichlorobenzene (DCB), to the (P3HT:PCBM) active layer while keeping a fixed amount for P3HT. To understand the effect of fullerene replacement with the inorganic metal oxide nanoparticles on different properties of resulting devices, a variety of techniques such as Current–Voltage (J–V) characteristics, Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), Ultravoilet-Visible (UV–Vis) Spectrophotometry and External Quantum Efficiency (EQE) were employed. The addition of TiO2 nanoparticles in the active layer improved the power conversion efficiency (PCE) of P3HT:PCBM devices. The addition of TiO2 nanoparticles using CB as solvent enhanced the absorption in visible region and also introduced a red shift in the absorption spectra. A significant increase in EQE was observed for devices with TiO2 nanoparticles in the active layer. Mixing TiO2 also increased the surface roughness of the active layer where TiO2 nanoparticles were found to agglomerate as their concentration increased relative to fullerene derivative. A complete agglomeration of TiO2 was observed in the absence of PCBM. 相似文献
In the polymer photovoltaic devices (PVDs), the performance of devices was strongly influenced by region-regularity, number average molecular weight and casting solvents of polymers. In this work, we fabricated p–n bulk-hetero-junction PVDs based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C60-butyric acid methyl ester (PCBM) using various solvents such as chloroform (CF), chlorobenzene (CB), dichlorobenzene (DCB), and mixed solvent (CF/CB, CF/DCB). Thin film of active layer with P3HT/PCBM was prepared by spin coating and thermal annealing at 150 °C with fixed thickness about 110 nm by adjusting solution concentration. The crystalline morphology and layered phase for the active layer were studied by atomic force microscopy and X-ray diffraction, respectively. We investigated the performance of solar cells according to different morphology and crystallinity of active layer by various solvent and mixed solvent. 相似文献
Inverted structure comes out to be a promising alternative for making polymer solar cells (PSC) with high efficiency and long-term stability. Vertically stacked functional layers with planar shapes often suffer contradictions in holding high optical absorption and excellent charge transfer/hindrance capability to construct well performed inverted PSC devices. Here, we give an example of rational control of the thickness of electron transport layer (ETL), hole transport layer (HTL) and organic active layer (OAL) to achieve a synergistic effect on promoting the overall photovoltaic behaviors. With in-depth exploration of the interaction between device performance and layer thickness, we obtain the optimized device ITO/ZnO Ncs (45 nm)/P3HT:PCBM (70 nm)/MoO3 (1 nm)/Ag (70 nm) exhibiting an Voc of 0.63 V, Jsc of 12.52 mA/cm2, FF of 54% and PCE of 4.26%. 相似文献
The interface between the active layer and the electrode is one of the most critical factors that could affect the device performance of polymer solar cells. In this work, based on the typical poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester(P3HT:PCBM) polymer solar cell, we studied the effect of the cathode buffer layer(CBL) between the top metal electrode and the active layer on the device performance. Several inorganic and organic materials commonly used as the electron injection layer in an organic light-emitting diode(OLED) were employed as the CBL in the P3HT:PCBM polymer solar cells. Our results demonstrate that the inorganic and organic materials like Cs_2CO_3, bathophenanthroline(Bphen), and 8-hydroxyquinolatolithium(Liq) can be used as CBL to efficiently improve the device performance of the P3HT:PCBM polymer solar cells. The P3HT:PCBM devices employed various CBLs possess power conversion efficiencies(PCEs) of 3.0%–3.3%, which are ca. 50% improved compared to that of the device without CBL. Furthermore, by using the doped organic materials Bphen:Cs_2CO_3 and Bphen:Liq as the CBL, the PCE of the P3HT:PCBM device will be further improved to 3.5%, which is ca. 70% higher than that of the device without a CBL and ca. 10% increased compared with that of the devices with a neat inorganic or organic CBL. 相似文献
A high‐efficiency bulk heterojunction organic photovoltaic cell (OPV) was achieved by the electrospray deposition method. The surface roughness of the P3HT:PCBM thin film can be reduced using the mixed solvent consisting of o‐dichlorobenzene (o‐DCB) and acetone. The effect of acetone concentration is related to its dielectric constant. Under an optimized concentration of acetone in o‐DCB (20 vol%), the P3HT/PCBM active layer with a smooth surface can be formed, and the power conversion efficiency of the OPV was 1.9%.
Inverted organic solar cells are fabricated using low-temperature-annealed ZnO film as an electron transport layer. Uniform ZnO films were prepared by spin coating a diethylzinc (DEZ) precursor solution in air, followed by annealing at 100 °C. Organic solar cells prepared on these ZnO films with a 1:1 P3HT:PCBM blend as the active layer show a high power conversion efficiency of 4.03 %, which is more than 10 % higher than the PCE of solar cells comprising ZnO prepared via a high-temperature sol–gel route. 相似文献
We present series of strategies to enhance efficiency of ZnO nanorods based organic/inorganic solar cells with spin-coated P3HT:PCBM blend as active layer. The performance of the as-fabricated devices is improved by controlling the size of ZnO nanorods, annealing temperature and time of active layer, surface modification of ZnO with PSBTBT. Optimized device of ITO/ZnO nanorod/P3HT:PCBM/Ag device with PSBTBT surface modification and air exposure reaches an efficiency of 2.02% with a short-circuit current density, open-circuit voltage and fill factor of 13.23 mA cm−2, 0.547 V and 28%, respectively, under AM 1.5 irradiation of 100 mW m−2, the increase in efficiency is 7-fold of the PSBTBT surface modified ITO/ZnO nanorods/P3HT:PCBM/Ag device compared with the unmodified one, which is own to the increased interface contact, expanded light absorption, tailored band alignment attributed to PSBTBT. We found exposure to air and surface modification is crucial to improve the device performance, and we discussed the mechanisms that affect the performance of the devices in detail. 相似文献
An improved power conversion efficiency (PCE) of bulk heterojunction organic photovoltaic cell (OPV) was achieved by inserting an n‐type [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) layer between the active layer and a metal electrode. The controlled substrate temperature was found to be a useful parameter for the multilayer structure (active layer/ PCBM) by the electrospray deposition method. Under optimized substrate temperature during the PCBM deposition, a multilayer structure could be formed, and the PCE was improved up to 1.94%.
In this work, we have presented a freestanding and flexible CNT-based film with sheet resistance of 60 ?/ and transmittance of 82% treated by nitric acid and chloroauric acid in sequence. Based on modified CNT film as a transparent electrode, we have demonstrated an ultrathin, flexible organic solar cell(OSC) fabricated on 2.5-μm PET substrate. The efficiency of OSC, combined with a composite film of poly(3-hexylthiophene)(P3HT) and phenyl-C61 butyric acid methyl ester(PCBM) as an active layer and with a thin layer of methanol soluble biuret inserted between the photoactive layer and the cathode, can be up to 2.74% which is approximate to that of the reference solar cell fabricated with ITO-coated glass(2.93%). Incorporating the as-fabricated ITO-free OSC with pre-stretched elastomer, 50% compressive deformation can apply to the solar cells. The results show that the as-prepared CNT-based hybrid film with outstanding electrical and optical properties could serve as a promising transparent electrode for low cost, flexible and stretchable OSCs, which will broaden the applications of OSC and generate more solar power than it now does. 相似文献
Hybrid organic/inorganic thin-film transistors (TFTs) with bottom-contact configuration were fabricated using the Laser Induced Forward Transfer (LIFT) process. The semiconducting polymer P3HT was laser printed from a donor to a receiver substrate in order to form the active layer of the TFTs. With a single laser pulse, P3HT pixels were successfully printed. The printed material was analyzed morphologically by means of Optical Microscopy and its thickness was measured by profilometry. In addition, structural characterization of P3HT thin films before and after laser printing took place by using UV-Visible absorption spectroscopy and X-Ray Diffraction. It was found that the crystallinity of the investigated films is improved upon annealing. An organic thin-film transistor (OTFT) with laser printed P3HT pixel as a channel layer was then fabricated. The OTFTs indicated a field-effect mobility up to 2.23?10?4 cm2/Vs and an on/off ratio on the order of 10–100. 相似文献
The semi-conductive poly(3-iodothiophene)(P3IT) films were fabricated by gas-phase polymerization through a chemical vapor deposition process. The P3IT nanoscale films have a high crystalline morphologies, and possessed a high Hall mobility up to 10 cm2/Vs. The degree of crystalline and the mobility values measured through Scanning Electron Microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy with structural analysis. These conductive thin films, possessing polycrystalline structures, have a very high mobility and are capable of being applied to organic electronic layers for electrical devices such as the thin film transistors and organic photovoltaic cells. 相似文献