Blend Of P3HT Research Articles

Fluorine substitution for aggregation transformation and exciton dissociation acceleration in non-fused electron acceptors

In order to enable low-cost manufacture of organic solar cells (OSCs), it is very important to develop non-fused electron acceptors to match with one of the cheapest polymer donors, poly(3-hexylthiophene) (P3HT). However, the lower exciton dissociation and charge transfer are still the main factors that limit the improvement of P3HT-based OSCs. Herein, we designed one class of A2-A1-D-A1-A2 type non-fused electron acceptors and synthesized BTA34 and F-BTA34 by introducing benzo[d][1,2,3] triazole as the bridged unit. The dominated H-aggregation in F-BTA34 affords high degree of crystalline and proper phase separation when blended with polymer P3HT, which ensure efficient exciton dissociation and higher charge carrier mobility. Consequently, P3HT:F-BTA34 devices demonstrate a better performance with higher short-circuit current and fill factor. The blend of P3HT:BTA34 exhibits a broader distribution of the mixing domains, resulting in relative longer-lived charge species. This work provides useful strategies to design non-fused electron acceptors to match with P3HT from the perspective of simultaneously improving exciton dissociation and suppressing charge recombination.

Tackling P3HT:Y‐Series Miscibility Through Advanced Processing for Tunable Aggregation

AbstractPolymer and small molecule blend thin films are of strong interest for organic electronics and particularly organic solar cells. The high miscibility in blends of ordinary P3HT and state‐of‐the‐art Y‐series non‐fullerene acceptors (NFAs) suppresses phase separation and aggregation challenging successful charge separation and transport. In a recent work, current‐induced doping (CID) is introduced, a method to precisely control the aggregation of Poly(3‐hexylthiophene) (P3HT) in solution. The highly ordered pre‐aggregation in solution is used here to control the P3HT aggregation in neat films and blends with Y12 (BTP‐4F‐12). This results in a 25‐fold increase in hole mobility in P3HT organic field‐effect transistor (OFET) devices and tunability of the P3HT aggregate quality in the presence of Y12 over large ranges. At the same time, particularly the Y12 long‐range ordering is heavily suppressed by increasing P3HT aggregation. However, solvent vapor annealing (SVA) leads to an extraordinarily high Y12 ordering, changes in the crystal orientation of Y12, and a further improvement of P3HT aggregation. A broad range of different degrees of aggregation of both materials can therefore be obtained in the final thin films solely by changing processing parameters without changing the composition of the material system.

Enhanced Gas Sensing Characteristics of a Polythiophene Gas Sensor Blended with UiO‐66 via Ligand Functionalization

AbstractConjugated polymers exhibit significant potential for use in gas sensors owing to their flexibility and straightforward preparation. However, the performance of organic gas sensors based on such materials is currently suboptimal owing to their poor charge‐transport properties and limited selectivity. To address this limitation, a novel strategy that involves blending a chemically modified metal–organic framework (MOF) material, UiO‐66, with a conjugated polymer is developed. The MOF porous material is chemically modified with polar nitrogen‐containing functional groups (amino and nitro groups) to create gas molecule adsorption sites. To evaluate the impact of these modifications on the sensing performance, experiments that combined the sensing performance with a density functional theory simulation are conducted. The findings reveal that gas sensors fabricated using an amine‐functionalized MOF blended with conjugated polymers exhibit significantly higher sensitivity than home polymer devices, the sensing performance of the UiO‐66‐NH2/P3HT blend film improved by a factor of two with a sensitivity of ≈2%/ppm and an LOD of 0.001 ppt. Additionally, these devices exhibit exclusive NO2‐sensing performance for other gases such as CO2 and SO2.

Thermal and optical properties of P3HT:PC70BM:ZnO nanoparticles composite films

The results of studies on the influence of zinc oxide nanoparticles (ZnO-NPs) on the structural, thermal and optical properties of thin films of mixtures of phenyl-C71-butyric acid methyl ester (PCBM) with poly[3-hexylthiophene] (P3HT) of various molecular weights are described in this article. The structural properties of the layers of: polymers, mixtures of polymers with fullerenes and their composites with ZnO-NPs were investigated using X-ray diffraction. Whereas their glass transition temperature and optical parameters have been determined by temperature-dependent spectroscopic ellipsometry. The presence of ZnO-NPs was also visible in the images of the surface of the composite layers obtained using scanning electron microscopy. These blends and composite films have also been used as the active layer in bulk heterojunction photovoltaic structures. The molecular weight of P3HT (Mw = 65.2; 54.2 and 34.1 kDa) and the addition of nanoparticles affected the power conversion efficiency (PCE) of the obtained solar cells. The determined PCE was the highest for the device prepared from the blend of P3HT:PCBM with the polymer of the lowest molecular weight. However, solar cells with ZnO-NPs present in their active layer had lower efficiency, although the open-circuit voltage and fill factor of almost all devices had the same values whether they contained ZnO-NPs or not. It is worth noting that thermal studies carried out using temperature-dependent ellipsometry showed a significant effect of the presence of ZnO-NPs on the value of the glass transition temperature, which was higher for composite films than for films made of a polymer-fullerene blend alone.

Will it blend? Exploring the viscoelastic characteristics of P3HT-polyborosiloxane blends towards flexible electronic materials.

Blending organic semiconducting polymers with elastomeric materials has been shown to be a successful method for improving the flexibility of wearable electronics. One such elastomer that has not been readily explored in combination with an organic semiconducting polymer is polyborosiloxane (PBS). PBS shows remarkable viscoelastomeric properties, due to the borate ester groups that crosslink the siloxane backbones, demonstrating a dynamic covalent crosslinking mechanism. The detailed study presented here showcases the properties of two different PBS elastomers and the effect of blending a well-known organic semiconducting polymer, poly(3-hexylthiophene) (P3HT). Compatibility studies showed that one elastomer blends more favourably than the other due to differences in the crosslinking density leading to the formation of P3HT crystallites within the blend. The viscoelastic properties of the PBS : P3HT blends are studied through detailed rheological experiments and the relaxation processes are discussed.

EXAMINING THE OPERATION OF AN INVERSELY STRUCTURED ORGANIC PHOTOVOLTAIC SYSTEM USING LAMINATED SILVER ELECTRODES.

The research looked into the performance of an organic photovoltaic (OPV) with an inverse structure and laminated silver electrodes. The goal was to investigate the properties of the PCMB:P3HT blend used in the active layer and how they relate to device performance. The findings from UV-Visible absorption spectroscopy, which examined the optical properties of the PCMB: P3HT blend, were presented in the results. The blend had high absorption between 584.55 and 623.33 nm and low absorption in the red and near-infrared regions of the spectrum. The transmittance spectra revealed low transmittance, especially between 400 and 635 nm. The absorption and extinction coefficients of the blended material were calculated and analysed. The absorption coefficient increased between 400 and 635 nm, while the extinction coefficient peaked at 617.81 nm. The optical energy bandgap of the blend was determined to be 1.94 eV. The photovoltaic characteristics of the solar cell were assessed using I-V and P-V measurements. The key parameters obtained were open-circuit voltage, short-circuit current, voltage at maximum power point, and current at maximum power point. The fill factor and efficiency of the solar cell were calculated to be approximately 0.6462 and 0.6989%, respectively. The research helps to better understand the performance characteristics of inverse structure OPVs with laminated silver electrodes. Further investigation and optimization of the device structure and materials may improve the fill factor and efficiency, thereby improving the performance and adoption of organic photovoltaics in renewable energy applications.

Fotovoltaik Hücrelerin Yüzey Morfolojisi ve Verimliliği Üzerinde Termal Tavlama Etkisi

Photovoltaics convert solar radiation into electrical current. For the present study, blends containing electron donor and acceptor are used instead of materials made with silicon. Carbon-based organic semiconductors are easy to process and have low fabrication costs. There are several fabrication steps playing important role in the photovoltaic device performance such as, substrate preparation, polymer-acceptor ratios in the blend, thermal annealing of the active layer and top electrode deposition. It has been shown that nanoscale morphology of the blend can be altered via thermal annealing treatment. As a result, efficiency is affected by surface roughness. The blend of P3HT: PCBM as donor: acceptor was used to fabricate thin films and photovoltaic cells. The power conversion efficiencies and surface morphologies of the devices annealed at various times were measured. Atomic force microscopy (AFM) images revealed that the surface roughness of the active layer is mainly affected by the annealing time, and the film with the roughest surface results in the most efficient solar cell.

Development of Multilevel Organic Phototransistor Memory using Conjugated/Insulating Polymer Blends with a Vertical Phase Separation

AbstractIn this work, a series of methacrylate‐based polymers bearing benzene (poly(benzyl methacrylate)), naphthalene (poly(2‐naphthyl methacrylate)), anthracene (poly(9‐anthracenyl methyl methacrylate), PAMA), and pyrene (poly(1‐pyrenemethyl methacrylate)) are blended with conjugated polymer of poly(3‐hexylthiophene) (P3HT) to perform vertical phase separation during spin‐coating. The bilayer structure of the conjugated/insulating polymer blend is driven by their mismatch in surface energy, and the blend films are applied in the phototransistor memory device with the bottom layer of methacrylate‐based polymer as a photoactive electret and the top layer of P3HT as a semiconducting channel. It is found that the vertical phase separation morphology, conjugation, and energy levels of the pendant arene groups in the methacrylate‐based polymers are highly related to the photoresponse, memory retention/endurance of the phototransistor memory. Therefore, the device comprising the polymer blend of P3HT and PAMA successfully produces a high current contrast of 105 to 254 nm light and 104 to 450 nm light over 104 s. This study provides a facile approach to the fabrication of high‐performance phototransistor memory devices.

Synthesis, Characterization and Optical Properties of PLA / P3HT Blends Thin Films

In this exploration Poly lactic corrosive (PLA) was orchestrated the ring-opening polymerization Poly lactic corrosive (PLA) blended with poly(3-hexylthiophene) (P3HT) which prepared by solution. Blends thin films Synthesis by spin coating technique and using Tetrahydrofuran (THF) as solvent. PLA powder was 'characterized by' 'X-ray' 'diffraction', '(FT-IR)'. pure Optical properties (PLA), (PLA)/P3HT blends thin films with different percentage of P3HT (0, 1, 2, and 3) wt% were investigated using UV-VS spectroscopy The results showed that the absorption, absorption coefficient, extinction coefficient and conductivity increase with increasing the rate of deformation P3HT, The energy gap decreases with increasing deformation.

Efficient p‐Doping with F6TCNNQ for Improving Performance of Polymer Photodetectors with Photomultiplication

Polymer photodetectors with photomultiplication (PM‐PPDs) are prepared with PC71BM:P3HT (1:100, wt/wt) active layers containing efficient hole‐transport channels and large amount of isolated electron traps. The solid additive F6TCNNQ is incorporated into PC71BM:P3HT blend films with rather low content of 0.02 wt%. The external quantum efficiency (EQE) and response speed of PM‐PPDs with F6TCNNQ additive in the active layer are much larger than those of PM‐PPDs without F6TCNNQ additive under the same bias. The EQE values at 400 and 625 nm can reach 5240% and 3050% for the PM‐PPDs with F6TCNNQ in active layers under −9 V bias, which is among the highest values for PM‐PPDs under the same bias. The performance improvement of PM‐PPDs with F6TCNNQ is primarily ascribed to the enhanced hole mobility in the active layer, leading to the increased response speed with rise time of 27.7 ms and fall time of 85 ms. This work indicates that performance of PM‐PPDs can be markedly enhanced by using p‐doping with strong oxidizing agents, beneficial for an enhancement in hole mobility in F6TCNNQ:PC71BM:P3HT active layers.

Dynamics of the sub-ambient gelation and shearing of solutions of P3HT and P3HT blends towards active layer formation in bulk heterojunction organic solar cells.

Organic solar cells (OSCs) containing an active layer consisting of a nanostructured blend of a conjugated polymer like poly(3-hexylthiophene) (P3HT) and an electron acceptor have the potential of competing against silicon-based photovoltaic panels. However, this potential is largely unfulfilled first due to interrelated production and stability issues of organic solar cells and second due to the unscalable nature of the generally employed spin coating process used for the fabrication of organic solar cells. Furthermore, alternatives to spin coating, especially relying on continuous polymer processing methods like extrusion and coating, cannot be readily applied due to the typically low shear viscosity and elasticity of polymer solutions making up the active layer. Recently, He et al. have reported that the gelation of P3HT with [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) under sub-ambient conditions can provide a new route to the processing of the active layers of bulk heterojunction solar cells. Furthermore, increases in power conversion efficiencies (PCEs) of the P3HT/PC60BM active layer were determined to be possible under certain shearing and thermal histories of the P3HT/PC60BM gels. Here oscillatory and steady torsional flows were used to investigate the gel formation dynamics of P3HT with a recently proposed non-fullerene acceptor o-IDTBR under sub-ambient conditions and compared with the gelation behavior of P3HT/PC60BM blends. The rheological material functions as well as the gel strengths defined on the basis of linear viscoelastic material functions, characterized via small-amplitude oscillatory shearing, were observed to be functions of the P3HT and o-IDTBR concentrations, the solvent used and the shearing conditions. Overall, the P3HT gels which formed upon quenching to sub-zero temperatures were found to be stable during small-amplitude oscillatory shear (linear viscoelastic range) but broke down even at the relatively low shear rates associated with steady torsional flows, suggesting that the shearing conditions used during the processing of gels of P3HT and blends of P3HT with small molecule acceptors can alter the gel structure, possibly leading to changes in the resulting active layer performance.

Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrent nearby the regime of the space charge-limited current

To understand the complex behaviors of photogenerated charge carriers within polymer-based bulk-heterojunction-type solar cells, the charge-carrier photogeneration and extraction dynamics are simultaneously estimated using a transient photocurrent technique under various external-bias voltages, and a wide range of excitation intensities are analyzed. For this purpose, conventional devices with 80 nm thick active layers consisting of a blend of representative P3HT and PTB7 electron-donating polymers and proper electron-accepting fullerene derivatives were used. After the correction for the saturation behavior at a high excitation-intensity range nearby the regime of the space charge-limited current, the incident-photon-density-dependent maximum photocurrent densities at the initial peaks are discussed as the proportional measures of the charge-carrier-photogeneration facility. By comparing the total number of the extracted charge carriers to the total number of the incident photons and the number of the initially photogenerated charge carriers, the external quantum efficiencies as well as the extraction quantum efficiencies of the charge-carrier collection during a laser-pulse-induced transient photocurrent process were obtained. Subsequently, the charge-carrier concentration-dependent mobility values were obtained, and they are discussed in consideration of the additional influences of the charge-carrier losses from the device during the charge-carrier extraction that also affects the photocurrent-trace shape.

Lithium‐Doped CuO Nanosheets: Structural Transformation, Optical, and Electrical Characteristics with Enhanced Photocatalytic and Solar Cell Performance

Energy and environmental stuff are two of the main worries for humanity, and nanoscience plays a key role in providing the solution. Huge nano‐research activities have attracted lot of attention in the current scenario. However, designing the material with enhanced optoelectronic properties remains the foremost challenge. In the present work, the Li doped CuO nanosheets are synthesized by the chemical route and examined in photovoltaics and environmental remediation applications. The crystallographic and optical study reveals that crystallite size and bandgap decrease with an increase in lithium‐doping concentration up to 5 mole % and beyond that a reverse trend is observed. Additionally, impedance study has shown the significant contribution of lithium‐ions to the total capacitance and resistivity. Further, the photoactivity of Cu1−xLixO nanosheets (optimum concentration of Cu1−xLixO NSs (x = 0.05)) is projected to the degradation of methylene blue (MB) and used to fabricate bulk heterojunction solar cell together with P3HT and PCBM blend, respectively. The ITO/PEDOT:PSS/P3HT:PC70BM:Cu1−xLixO (x = 0.05)/LiF/Al solar cell realized higher power‐conversion efficiency η ˜ 3.91 than their corresponding pristine device η ˜ 2.98 with enhanced photocurrent density from 9.026 to 11.56 mA cm−2. The proliferation in photocatalysts and solar cells efficiency of Cu1−xLixO (x = 0.05) is mainly attributed to the higher light absorption and lesser electron‐hole recombination. The approach for the synthesis of Cu1−xLixO NSs as potential donor material and device prototypes fabricated is completely safe and cost‐effective.

Fabrication and characterization of a stemless plastic scintillation detector.

To fabricate a stemless plastic scintillation detector (SPSD) and characterize its linearity and reproducibility, and its dependence on energy and dose per pulse; and to apply it to clinical PDD and output factor measurements. An organic bulk heterojunction photodiode was fabricated by spin coating a blend of P3HT and PCBM onto an ITO-coated glass substrate and depositing aluminum top contacts. Eljen scintillators (~5×5×5mm3 ; EJ-204, EJ-208, and EJ-260) or Saint-Gobain scintillators (~3×3×2mm3 ; BC-400 and BC-412) were placed on the opposite side of the glass using a silicone grease (optical coupling agent) creating the SPSD. Energy dependence was measured by using 100, 180, and 300kVp photon beams from an orthovoltage treatment unit (Xstrahl 300) and 6 and 10MV photons from a Varian TrueBeam linear accelerator. Linearity, dose per pulse dependence, output factors, and PDDs were measured using a 6MV photon beam. PDDs and output factors were compared to ion chamber measurements. A control device was fabricated by substituting polystyrene (PS) for the P3HT/PCBM layer. No photocurrent should be generated in the control device and so any current measured is due to Compton current in the electrodes, wires, and surroundings from the irradiation. Output factors were corrected by subtracting the signal measured using the control device from the photodiode measured signal to yield the photocurrent. Each SPSD had excellent linearity with dose having an r2 of 1 and sensitivities of 1.07 nC/cGy, 1.04 nC/cGy, 1.00 nC/cGy and 0.10 nC/cGy, and 0.10nC/cGy for EJ-204, EJ-208, EJ-260 (5×5×5mm3 volumes), BC-400, and BC-412 (3×3×2mm3 volumes), respectively. No significant dose per pulse dependence was measured. Output factors matched within 1% for the large scintillators for field sizes of 5×5cm2 to 25×25cm2 , but there was a large under-response at field sizes below 3×3cm2 . After correcting the signal of the small scintillators by subtracting the current measured using the PS control, the output factors agreed with the ion chamber measurements within 1% from field sizes 1×1cm2 to 20×20cm2 . The impact of Cerenkov emissions in the scintillator was effectively corrected with a simple reflective coating on the scintillator. In comparison to a 6MV photon beam, the large scintillator SPSDs exhibited 37%, 52%, and 73% of the response at energies 100 kVp, 180 kVp and 300 kVp, respectively. The principle of the SPSD was demonstrated. Devices had excellent linearity, reproducibility, and no significant dose per pulse dependence, and a simple reflective coating was sufficient to correct for Cerenkov emissions from within the scintillator. The devices demonstrated similar energy dependence to other scintillator detectors used in a radiotherapy setting.

Radiation induced photocurrent in the active volume of P3HT/PCBM BHJ photodiodes

Abstract The purpose of this work is to fabricate and characterize the response of a P3HT/PCBM bulk heterojunction organic photodiode to photon beams with respect to dose rate, total dose, and energy. A bulk heterojunction (BHJ) organic photodiode was fabricated by spin coating a blend of P3HT and PCBM onto an ITO-coated glass substrate and then depositing aluminum top contacts. Control devices were made by spin coating polystyrene instead of the P3HT/PCBM layer. The devices were irradiated with a 6 MV photon beam with dose rates of 100–600 cGy/min. Energy dependence was measured for energies of 100, 180, and 300 kVp and 6 and 10 MV. Photocurrent in the BHJ was calculated by subtracting the average current measured using the four PS devices from that measured with each of the four BHJ diodes to correct for current collected by the electrodes and the wires/connectors. The sensitivities of the four BHJ devices were within the range of 3.7–4.3 pC/cGy. The range of values is mostly due to inter-device variation and not due to variation between readings on the ITO and Al electrodes of a single device. The diodes exhibit an energy dependence with more than 4 times the response at 100 kVp than at 6 MV. The direction and magnitudes of the measured currents after correction for the electrode/lead currents were consistent with photocurrent. The photocurrents increased linearly with dose rate indicating they could be suitable in radiation sensing applications.

Enhancing P3HT/PCBM blend stability by thermal crosslinking using poly(3-hexylthiophene)-S,S-dioxide

A statistical copolymer containing thiophene and thiophene-S,S-dioxide rings was utilized as a thermal crosslinker in a blend of P3HT and PCBM, demonstrating an effective strategy for preventing agglomeration of PCBM and enhancing blend stability.

RGO induced structural and microstructural properties of P3HT in the performance and stability of polymer solar cells

With recent technological advancement, interest towards energy efficient flexible devices have grown appreciably. Graphene is one of the most renowned material due to its exclusive physical properties together with ultrahigh specific surface area and high carrier mobility of ∼104 V.s. Filler modified physical properties of reduced graphene oxide (rGO)/Poly[3-hexylthiophene-2,5-diyl] (P3HT) blends with [6,6]-Phenyl C61 butyric acid methyl ester (PCBM) have been reviewed carefully in active layer of the organic solar cells. Physio-chemical properties of rGO modified P3HT blends have been analyzed using peculiar characterization tools such as x-ray diffraction (XRD), scanning electron microscope (SEM), UV–visible (UV–vis), Fourier transform infrared, Raman and photo luminescence (PL) spectroscopic techniques along with cyclic-voltammetry measurements. Open-circuit voltage (Voc) of 0.66 V, current-density (Isc) of ∼10.6 mA cm−2 and efficiency of ∼3.71% have been ascertained for the device with 1.6 wt% of rGO in the active layer. RGO induced additional exciton dissociation sites and efficient carrier transport through the conducting rGO network in the active layer is attributed for the improved performance of the solar cells. The effect of introducing ZnO electron transport layer (ETL) on the device performance as well as the stability of the solar cell is investigated.

The Role of Morphology in Optically Switchable Transistors Based on a Photochromic Molecule/p‐Type Polymer Semiconductor Blend

AbstractThe correlation between morphology and optoelectronic performance in organic thin‐film transistors based on blends of photochromic diarylethenes (DAE) and poly(3‐hexylthiophene) (P3HT) is investigated by varying molecular weight (Mw = 20–100 kDa) and regioregularity of the conjugated polymer as well as the temperature of thermal annealing (rt‐160 °C) in thin films. Semicrystalline architectures of P3HT/DAE blends comprise crystalline domains, ensuring efficient charge transport, and less aggregated regions, where DAEs are located as a result of their spontaneous expulsion from the crystalline domains during the self‐assembly. The best compromise between field‐effect mobility (μ) and switching capabilities is observed in blends containing P3HT with Mw = 50 kDa, exhibiting μ as high as 1 × 10−3 cm2 V−1 s−1 combined with a >50% photoswitching ratio. Higher or lower Mw than 50 kDa are found to be detrimental for field‐effect mobility and to lead to reduced device current switchability. The microstructure of the regioregular P3HT blend is found to be sensitive to the thermal annealing temperature, with an increase in μ and a decrease in current modulation being observed as a response to the light‐stimulus likely due to an increased P3HT‐DAE segregation, partially hindering DAE photoisomerization. The findings demonstrate the paramount importance of fine tuning the structure and morphology of bicomponent films for leveraging the multifunctional nature of optoelectronic devices.

Ellipsometric studies for thin polymer layers of organic photovoltaic cells

In this study, ellipsometry was used to study thin films on organic photovoltaic cells. The investigated cells contained a traditional donor-acceptor structure as the active layer in the form of a bulk heterojunction. The tested photovoltaic cells had the following structure: ITO/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)/poly (3-hexylthiophene-2-diyl) (P3HT) + 1,3-phenyl-6-fluorine-1H-pyrazolo[3,4-b]quinoline (PQ)/Al. The active layer was a blend of P3HT and a compound from the pyrazoloquinoline group with a low molecular weight marked as PQ. The ITO film acted as the electrode collecting the holes. The PEDOT:PSS layer was used to smoothen the ITO film and facilitate the transport of holes. The layers were tested using spectroscopic ellipsometry (SE), and the spectral dispersion of optical constants was determined in a wavelength range of 300–1700 nm. The appropriate theoretical models were then fitted to the SE measurement results. This information was used to determine the thickness of the layers and the dispersion relation of refractive and extinction indices. The temperature dependence of refractive indices of polythiophene layers during the heating and cooling process is also presented for a temperature range of 25–110 °C. Additionally, the authors calculated thermo-optic and thermal expansion coefficients and characterized the conditions of thermal stability of the layers and reversibility issues in thermal processes.

The power conversion efficiency optimization of the solar cells by doping of (Au:Ag) nanoparticles into P3HT:PCBM active layer prepared with chlorobenzene and chloroform solvents

We report to enhance the power conversion efficiency of organic solar cells by embedding of (Au:Ag) nanoparticles (NPs) into P3HT:PCBM active layer of the organic solar cells. Furthermore, the effect of solvents based on chlorobenzene and chloroform on the P3HT:PCBM active layer has been investigated for comparison. As known, the performance of organic solar cells based on the blend of regioregular P3HT:PCBM is strongly influenced by blend composition. For this purpose, ITO/PEDOT:PSS/P3HT:PCBM/(Au:Ag)NPs/LiF/Al quaternary hybrid solar cells were fabricated. Absorption, AFM, SEM and XRD measurements of the quaternary hydride active layers prepared with chlorobenzene (CB) and chloroform (CF) solvents were obtained. The optical energy band gap of the hybrid active layer was calculated. The highest PCE values were obtained for 1.2% Au: 0.3% Ag NPs ratios and the study has been focused on these values. (Au:Ag) NPs in the active layer increased the power conversion efficiency (PCE) of the device from 2.11% to 3.29% and to 2.27% for prepared with CB and CF solvents, respectively. This increase was explained by the scatter of the incident light from the NPs and an enhancement of light absorption in the active layer of the solar cell, increasing the optical path distance.