Incorporation of SiO2 dielectric nanoparticles for performance enhancement in P3HT:PCBM inverted organic solar cells

It is well known that organic solar cells (OSCs) with inverted geometry have not only demonstrated a better stability and longer device life time but also have shown improved power conversion efficiency (PCE). Recent studies exhibit that incorporation of metal and/or semiconducting nanoparticles (NPs) can further increase the PCE for OSCs. In this present work, we have synthesized SiO₂ NPs of various sizes (25, 50, 75 and 100 nm) using the modified Stober method and incorporated them into P3HT:PCBM photoactive layer and ZnO based electron transport layer (ETL) in order to investigate the light trapping effects in an OSC. Absorption studies have shown a considerable increase in photo absorption in both cases. The fabricated devices demonstrated 13% increase in the PCE when SiO₂ NPs are incorporated in P3HT:PCBM photoactive layer, whereas PCE was increased by 20% when SiO₂ NPs are incorporated in ZnO based ETL. Mott–Schottky analysis and impedance spectroscopy measurements have been carried out to determine the depletion width and global mobility for both the devices. The possible reason for PCE enhancement and the role of SiO₂ NPs in active layer and ZnO ETL are explained on the basis of the results obtained from Mott–Schottky analysis and impedance spectroscopy measurements.     

Performance improvement mechanisms of P3HT:PCBM inverted polymer solar cells using extra PCBM and extra P3HT interfacial layers

A novel P3HT:PCBM inverted polymer solar cell (IPSC) was fabricated and investigated. An extra PCBM and an extra P3HT interfacial layers were inserted into the bottom side and the top side of the P3HT:PCBM absorption layer of the IPSCs to respectively enhance electron transport and hole transport to the corresponding electrodes. According to the surface energy, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) measurement results, the extra PCBM interfacial layer could let more P3HT to form on the top side of the P3HT:PCBM blends. It revealed that the non-continuous pathways of P3HT in the P3HT:PCBM absorption layer could be reduced. Consequently, the carrier recombination centers were reduced in the absorption layer of IPSCs. The power conversion efficiency (PCE) of the P3HT:PCBM IPSCs with an extra PCBM interfacial layer greatly increased from 3.39% to 4.50% in comparison to the P3HT:PCBM IPSCs without an extra PCBM interfacial layer. Moreover, the performance of the P3HT:PCBM IPSCs with an extra PCBM interfacial layer could be improved by inserting an extra P3HT interfacial layer between the absorption layer and the MoO₃ layer. The PCE of the resulting IPSCs increased from 4.50% to 4.97%.     

Flexible solar cells based on PCBM/P3HT heterojunction

[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) / poly (3-hexylthiophene) (P3HT) heterojunction has not only the absorption in ultraviolet light for PCBM,but also the absorption in visible light for P3HT, which widens the incident light harvest range, improving the photoelectrical response of hybrid solar cell effectively.Using conducting polymers blend heterojunetion consisting of C60 derivatives PCBM and P3HT as charge carrier transferring medium to replace I3-/I- redox electrolyte and dye, a novel flexible solar cell was fabricated in this study.The influence of PCBM/P3HT mass ratio on the photovoltaic performance of the solar cell was also studied.flexible solar cell achieved a light-to-electric energy conversion efficiency of 1.04%, an open circuit voltage fill factor (FF) of 0.46.     

Effects of PCBM concentration on the electrical properties of the Au/P3HT:PCBM/n-Si (MPS) Schottky barrier diodes

In this study, the gold/poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester/n-type silicon (Au/P3HT:PCBM/n-Si) metal–polymer–semiconductor (MPS) Schottky barrier diodes (SBDs) were investigated in terms of the effects of PCBM concentration on the electrical parameters. The forward and reverse bias current–voltage (I–V) characteristics of the Au/P3HT:PCBM/n-Si MPS SBDs fabricated by using the different P3HT:PCBM mass ratios were studied in the dark, at room temperature. The main electrical parameters, such as ideality factor (n), barrier height (Φ_B0), series resistance (R_s), shunt resistance (R_sh), and density of interface states (N_ss) were determined from I–V characteristics for the different P3HT:PCBM mass ratios (2:1, 6:1 and 10:1) used diodes. The values of n, R_s, Φ_B0, and N_ss were reduced, while the carrier mobility and current were increased, by increasing the PCBM concentration in the P3HT:PCBM organic blend layer. The ideal values of electrical parameters were obtained for 2:1 P3HT:PCBM mass ratio used diode. This shows that the electrical properties of MPS diodes strongly depend on the PCBM concentration of the P3HT:PCBM organic layer. Moreover, increasing the PCBM concentration in P3HT:PCBM organic blend layer improves the quality of the Au/P3HT:PCBM/n-Si (MPS) SBDs which enables the fabrication of high-quality electronic and optoelectronic devices.     

A thermodynamic and kinetic description of PCBM phase segregation and aggregation in P3HT:PCBM blends

The kinetics and thermodynamics of PCBM phase segregation and aggregation in P3HT:PCBM blends has been studied. We develop a thermodynamic model for PCBM phase segregation in P3HT:PCBM blends which explains the formation of nanoscale crystallites which subsequently diffuse and coalesce into larger PCBM aggregates. We show that the formation of nanoscale crystallites during the film making process prevents spinodal decomposition of the P3HT:PCBM blends even at PCBM weight fractions above the spinodal decomposition boundary for the system. Finally, we demonstrate that the observed aggregate morphology can be understood in terms of a kinetic model based on the diffusional flux lines of PCBM crystallite which, in turn, govern the evolution of the macroscopic growth front.     

Effect of fullerene doping on the electrical properties of P3HT/PCBM layers

Poly (3-hexylthiophene-2, 5-diyl) (P3HT) and its blend with Phenyl-C₆₁-Butyric acid-Methyl-Ester (PCBM) and fullerene (C₆₀) thin films were prepared and their electrical properties for memory applications were studied. Due to doping, a sharp decrease in the resistance for a P3HT:PCBM:C₆₀ device was observed at around 70 °C which makes it useful for thermal switching applications. Addition of C₆₀ to P3HT:PCBM blend gave a high value for R_RESET/R_SET in thermal switching. For bias switching, threshold voltage reduces to 1.4 V from 25 V with the addition of C₆₀ to P3HT layer.     

Effect of voltage sweep direction on the performance evaluation of P3HT : PCBM solar cells

Investigations on the effect of direction of voltage sweeps, on the current density–voltage (J–V) characteristics in polymer bulk‐heterojunction solar cells, based on the blend of poly(3‐hexylthiophene) (P3HT) and phenyl [6,6] C₆₁ butyric acid methyl ester (PCBM), are reported with time. On the freshly prepared device, the direction of the voltage sweep did not have any effect; however, as the device started degrading, the change in direction of the voltage sweep resulted into different characteristics. Analysis beyond complete degradation, when all the photovoltaic parameters reduced to zero, revealed some interesting results. The J–V characteristics, measured with voltage sweep from −ve to +ve voltage, both in the dark and under illumination, were observed to pass through the second quadrant. On the other hand, with the change in the direction of voltage sweep, viz. from +ve to −ve voltage, the characteristics both in the dark and under illumination passed through the fourth quadrant. These results have been explained on the basis of polarization of the degraded active layer due to applied external voltage. This is an important effect and is observed to depend on the applied voltages during performance evaluation and becomes more prominent with time. This effect puts a question mark on the correctness of the method for calculation of the parameters of a degraded device. Studies on degradation of P3HT : PCBM solar cells showed that both the short circuit current density (J_sc) and the power conversion efficiency (η) decay exponentially, whereas the open circuit voltage (V_oc) decays almost linearly with time. Copyright © 2012 John Wiley & Sons, Ltd.     

Stabilization of poly(3-hexylthiophene)/PCBM morphology by hydroxyl group end-functionalized P3HT and its application to polymer solar cells

A new concept to stabilize the morphology of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) blend through H-bond formation by using a hydroxyl group end-functionalized P3HT (HOC-P3HT-COH) as a compatibilizer is presented. Domain size of the PCBM crystals in the annealed P3HT/PCBM film is diminished with addition of HOC-P3HT-COH. Surface roughness of the P3HT/PCBM film also becomes smoother with addition of HOC-P3HT-COH. Thermal stability of solar cell device is improved significantly through the H-bond formation between HOC-P3HT-COH and PCBM. A high performance and thermal stable polymer solar cell with 4.06% power conversion efficiency under AM1.5G irradiation is fabricated with 5% HOC-P3HT-COH in P3HT/PCBM layer.     

Effect of incorporation of CdS NPs on performance of PTB7: PCBM organic solar cells

It has been well known that incorporation of nano-heterostructures of various metals, semiconductors and dielectric materials in the active layer of organic solar cells (OSCs) helps in improving power conversion efficiency (PCE). In the present study, we demonstrated microwave synthesis of CdS nanoparticles (NPs) for their application in one of most efficient OSCs consisting of poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl] [3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]thiophenediyl]] (PTB7): [6,6]-phenyl C₇₁-butyric acid methyl ester (PCBM) photoactive blend. This is crucial to fully explore the promising features of low cost and scalability in organic-inorganic hybrid solar cells. Synthesized CdS NPs are slightly elongated and highly crystalline with their absorption lies in the visible region as confirmed by High resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), UV–Vis absorption spectroscopy studies. Our experimental results for the devices in an inverted geometry having a structure ITO/ZnO/PTB7: CdS: PCBM/MoO₃/Ag has shown increase in Jsc and PCE by nearly 10%. However, it was observed that this increase is only when NPs were added in the low concentration in active layer. UV–Vis absorption spectroscopy, Photoluminescence (PL) and atomic force microscopy (AFM) studies were carried out in order understand the device performance.     

Incorporation of silver and gold nanostructures for performance improvement in P3HT: PCBM inverted solar cell with rGO/ZnO nanocomposite as an electron transport layer

Inefficient light absorption and inefficient charge separation are considered as two major impediments for the efficiency improvement in bulk heterojunction organic solar cells (BHJ OSCs). In this work, we report the simultaneous role of modified electron transport layer (ETL) and photoactive layers on the performance of poly (3-hexylthiophene), [6, 6]-phenyl C61-butyric acid methyl ester (P3HT: PCBM) BHJ OSCs. To modify the ETL, composite of reduced graphene oxide (rGO) (0.4 wt %) and ZnO nanoparticles (NPs) was used, which resulted in efficiency enhancement from 3.13 to 3.81%, as compared to a value of 3.13% when only ZnO was used. Thereafter, to improve upon the optical absorption properties, the photoactive layer is modified by embedding nanoparticles and nanorods of Ag and Au into it. The size of Ag and Au nanoparticles were chosen to be 50 nm while the dimensions of Ag and Au nanorods were so controlled to obtain length of approx. 50 nm and width of ∼10 nm. All the devices were fabricated in inverted geometry and 20 wt% nanostructures embedded devices showed the best results. For Ag and Au NPs embedded devices, the maximum power conversion efficiency was found to be 4.21% and 4.44%, respectively. On the other hand, for Ag and Au NRs embedded devices, the maximum efficiency was 4.37% and 4.85%, respectively. For comparison, the control devices where no nanostructures were embedded, which shows efficiency of 3.81%. Therefore, an overall enhancement in efficiency was nearly 1.21 and 1.1, 1.16, 1.14, 1.27 fold after modifying ETL as well as the active layer. The reasons for performance improvement were ascribed to better charge extraction properties of ETL, enhanced light absorption due to localized surface plasmon resonance (LSPR) and efficient light scattering by the nanostructures and improved global mobilities.     

Modular construction of P3HT/PCBM planar-heterojunction solar cells by lamination allows elucidation of processing–structure–function relationships

Contrary to polymer solar cells with bulk-heterojunction active layers, devices with planar-heterojunction active layers allow the decoupling of active layer phase separation from constituent crystallization, and their relative influence on device performance. We fabricated planar-heterojunction devices by first processing the electron donor and electron acceptor in isolation; they were subsequently laminated across the donor–acceptor interface to establish electrical contact. Thermal annealing was intentionally avoided after lamination to maintain the pristine charge transfer interface. Lamination thus obviates the need for solvent orthogonality; more importantly, it provides independent process tuning of individual organic semiconductor layers, ultimately allowing control over constituent structural development. We found the short-circuit current density of planar-heterojunction solar cells comprising poly(3-hexyl thiophene), P3HT, and [6,6]-phenyl-C₆₁-butyric acid methyl ester, PCBM, as the electron donor and acceptor, respectively, to be generally independent of the annealing history of P3HT. On the contrary, thermal annealing PCBM prior to lamination mainly led to a reduction in short-circuit current density. This deterioration is correlated with the development of preferentially oriented PCBM crystals that hinders electron transport in the vertical direction.     

退火方式及PCBM阴极修饰层对聚合物太阳电池的影响

研究了不同退火方式及PCBM阴极修饰层对聚合物太阳电池性能的影响。与前退火相比,后退火的器件性能显著提高,电池的开路电压Voc由0.36V增加到0.60V,能量转换效率η从0.85%提高到1.93%,短路电流密度Jsc和填充因子FF也有不同程度的改善;在电池的活性层与Al电极间沉积一定厚度的PCBM阴极修饰层也能改善电池的性能,当PCBM厚度为3nm时,聚合物太阳电池在100mW.cm-2强度光照下,Voc为0.59V,Jsc为6.43mA.cm-2,FF为55.1%,η为2.09%。     

Electrical and interfacial properties of Au/P3HT:PCBM/n-Si Schottky barrier diodes at room temperature

In this study, a gold/poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester/n-type silicon (Au/P3HT:PCBM/n-Si) metal-polymer-semiconductor (MPS) Schottky barrier diode (SBD) was fabricated. To accomplish this, a spin-coating system and a thermal evaporation were used for preparation of a P3HT/PCBM layer system and for deposition of metal contacts, respectively. The forward- and reverse-bias current–voltage (I–V) characteristics of the MPS SBD at room temperature were studied to investigate its main electrical parameters such as ideality factor (n), barrier height (Φ_B), series resistance (R_s), shunt resistance (R_sh), and density of interface states (N_ss). The I–V characteristics have nonlinear behavior due to the effect of R_s, resulting in an n value (3.09) larger than unity. Additionally, it was found that n, Φ_B, R_s, R_sh, and N_ss have strong correlation with the applied bias. All results suggest that the P3HT/PCBM interfacial organic layer affects the Au/P3HT:PCBM/n-Si MPS SBD, and that R_s and N_ss are the main electrical parameters that affect the Au/P3HT:PCBM/n-Si MPS SBD. Furthermore, a lower N_ss compared with that of other types of MPS SBDs in the literature was achieved by using the P3HT/PCBM layer. This lowering shows that high-quality electronic and optoelectronic devices may be fabricated by using the Au/P3HT:PCBM/n-Si MPS SBD.     

Effects of exciton blocking layer and cathode electrode work function on the performance of polymer solar cells

In this study the effects of some important processing and post-processing treatments on the performance of poly(3-hexylthiophene-2,5-diyl) (P3HT):[6,6]-phenyl-C₆₁-butyric acid methyl ester ([60]PCBM) solar cells were investigated. These parameters included the active layer film formation period, thermal annealing, electrical treatment, cathode work function modification, and exciton blocking layer type and thickness. Polymer bulk heterojunction solar cells having a glass/indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/P3HT:PCBM/(Ca or LiF)/Al structure were fabricated. The morphology of the active layer was investigated using atomic force microscopy. The results showed that the morphology state of the active layer exactly after spin coating process was very important parameter, which could dictate different responses of solar cells to a certain treatment. Using solvent additives to prolong the film formation period and storing in small dish could reach the morphology of the active layer near its best state in which there was no need to apply common post-treatment processes. A thickness at about 20 nm was required for Ca layer to effectively act as exciton blocking layer while LiF with 1 nm thickness worked better.     

Laser-induced crystallization and conformation control of poly(3-hexylthiophene) for improving the performance of organic solar cells

Femto-second laser irradiation on P3HT:PCBM solutions have been demonstrated to have a significant impact on the conformational structures and photovoltaic performance of the resultant thin films. The crystallinity and edge-on/face-on conformations of P3HT and the aggregation of PCBM can be manipulated by controlling the wavelength (400–800 nm) and illumination duration (1–3 h) of the lasers. Grazing incidence wide- and small-angle X-ray scattering (GIWAXS and GISAXS) have been simultaneously utilized to characterize the nanostructures of the P3HT:PCBM blend films spin-cast from pristine and laser-irradiated solutions. The results show that the crystallinity, π-π* stacking and face-on conformations of P3HT can be enhanced as a result of the laser irradiation at 500 nm for 3 h. Furthermore, the diffusion and aggregation of PCBM molecules are suppressed by the photo-induced dimerization, as evidenced by the Raman spectra of the films cast from laser-irradiated PCBM solutions. The time-resolved fluorescence decay profiles show the charge transfer efficiency is improved, which may correlate to the supramolecular ordering of the polythiophene chains and the optimized phase separation in P3HT:PCBM composite. In the P3HT:PCBM active layer of the organic solar cells, more efficient charge transport and fine interpenetrating networks can be achieved due to the improved conformational microstructures. Consequently, the short-circuit current densities and power conversion efficiencies can be enhanced in organic solar cells based on the laser-irradiation processed P3HT:PCBM solutions.     

High efficient ITO free inverted organic solar cells based on ultrathin Ca modified AZO cathode and their light soaking issue

Aluminum doped zinc oxide (AZO) was used to be the cathode instead of indium-tin-oxide (ITO) in the poly (3-hexylthiophene-2,5-diyl):[6,6]-phenyl C₆₁ butyric acid methyl ester (P3HT:PCBM) based bulk heterojunction inverted organic solar cells (IOSCs). For the AZO only IOSC, the device shows a poor power conversion efficiency (PCE) of 1.34% and a light soaking issue related to the energy barrier at the AZO/P3HT:PCBM interface. When a 5 nm Ca modifying layer is inserted between AZO and P3HT:PCBM, the obtained AZO/Ca (5 nm) IOSC shows an increased PCE from 1.74% to 2.69% after 15 min illumination. It is thought that the increased photoconductivity of AZO/Ca (5 nm) film upon illumination and the enhanced electron transport across the AZO/Ca interface may be responsible for the light soaking issue. When an ultrathin Ca modifying layer of 1 nm is employed, a further improved PCE of 3.17% is obtained, and remarkably, no light soaking issue is observed in this case. However, this unexpected issue appears after the un-encapsulated AZO/Ca (1 nm) IOSC has been stored in air for several days, which may be due to the energy loss in the electron transport across the interface between partly oxidized Ca and AZO layers induced by the oxidization of Ca. Furthermore, the AZO/Ca (1 nm) IOSC has a comparable PCE to the referenced ITO/Ca (1 nm) IOSC and presents a better air-stability. It is thus concluded that the AZO cathode is a promising alternative of ITO to fabricate the high efficient and long-lifetime IOSCs.     

High-efficiency inverted polymer solar cells via dual effects of introducing the high boiling point solvent and the high conductive PEDOT:PSS layer

Polymer solar cells (PSCs) are of great interest in the past decade owing to their potentially low-cost in the manufacturing by the solution-based roll to roll method. In this paper, a novel inverted device structure was introduced by inserting a high conductive PEDOT:PSS (hcPEDOT:PSS) layer between the Au nanoparticles (NPs)-embedded hole transport layer (PEDOT:PSS) and the top electrode layer. Power conversion efficiency (PCE) initially reached up to 4.51%, illustrating ∼10% higher compared with the device similarly enhanced by Au NPs plasmonics where only one PEDOT:PSS layer with the embedded Au NPs was used in single bulk heterojunction inverted PSCs based on the poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methylester (P3HT:PCBM). The PCE was further improved from 4.51% to 5.01% by adding the high-boiling point solvent of 1,8-diiodooctane (DD) into the active layer, presenting ∼20% enhancement in PCE through dual effects of introducing the high boiling point solvent and the high conductive PEDOT:PSS layer. Morphologies of the active layers were characterised by SEM and AFM separately in the paper.     

Structure difference of sorbitol derivatives influences the crystallization and performance of P3OT/PCBM organic photovoltaic solar cells

In this work, we compare the effects of sorbitol derivatives (1,3:2,4-dibenzylidene sorbitol (DBS), 1,3:2,4-di(p-methylbenzylidene) sorbitol (MDBS) and 1,3:2,4-di(3,4-dimethylbenzylidene) sorbitol (DMDBS)) on the performances of poly(3-octyl thiophene)/[6,6]-phenyl C₆₁-butyric acid methyl ester (P3OT/PCBM) bulk heterojunction (BHJ) organic photovoltaic (OPV) devices and explore the mechanism. Differential scanning calorimetry (DSC) and atomic force microscopy (AFM) measurements indicate that DBS, MDBS and DMDBS are nucleating agents of P3OT. DMDBS has the strongest molecular polarizability and exhibits the best propensity for self-assembly in 1,2-dichlorobenzene (ODCB). The strong π-π stacking of aromatic benzylidene group and the high density of the fibrillary aggregates supply more nucleation surfaces for P3OT, leading DMDBS has the highest nucleation efficiency (NE). Sorbitol derivatives accelerate the crystallization rate (G) of P3OT with the order as G_P3OT/DMDBS > G_P3OT/MDBS > G_P3OT/DBS > G_P3OT. The acceleration of the crystallization increases the number of tie molecules, causing the improvement of the connectivity between ordered regions, resulting dramatically increasing the carrier transport of P3OT. G_P3OT/DMDBS is highest, the connectivity between ordered regions is best in P3OT with DMDBS. UV–vis measurement indicates that the intra-chain order of P3OT reduces with the addition of sorbitol derivative, and the intra-chain order of P3OT with DMDBS is lowest. The P3OT/PCBM/sorbitol derivative BHJ OPV devices were fabricated and show that the short circuit current J_{SC P3OT/DMDBS} > J_{SC P3OT/MDBS} > J_{SC P3OT/DBS} > J_{SC P3OT}. It hints that the connectivity of tie molecules plays a significant role in defining semiconducting polymer transport characteristics, and is perhaps more important than molecular level interactions (inter- and intra-chain order) for efficient macroscopic charge carrier transport. Finally, it shows that adding sorbitol derivatives can improve the power conversion efficiency (PCE) of P3OT/PCBM BHJ OPV device, the best PCE as 1.77% is obtained in the P3OT/PCBM/DMDBS device.     

Enhancing the short-circuit current,efficiency of inverted organic solar cells using tetra sulfonic copper phthalocyanine (TS-CuPc) as electron transporting layer

Efficient bulk-heterojunction polymer solar cells based on poly(3-hexylthiophene) (P3HT) blended with a fullerene derivative, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) were fabricated in inverted configuration by using copper phthalocyanine-3,4′,4′′,4′′′tetra-sulfonated acid tetrasodium salt (TS-CuPc) as the electron collecting layer and MoO₃ as hole collecting layer. TS-CuPc is observed to be critical for the device performance, significantly enhancing the Jsc and the PCE compared to devices based on TiOx. The optimal thicknesses of MoO₃ and TS-CuPc were 10 nm and 15 nm, respectively. Based on these optimal parameters, the PCE of 3.6% was obtained compared to 3.4% for the reference TiOx/P3HT:PCBM/MoO₃/Ag.     

Annealing-free multi-thermal techniques comprising aging,cycling and seeding to enhance performance of thick P3HT:PCBM photovoltaic cells via developing hairy crystals

Distinct multi-thermal treatments comprising cycling, aging, and seeding were introduced to prepare very thick bulk heterojunction (BHJ) active layers (ca. 800 nm) of poly(3-hexylthiophene) (P3HT):phenyl-C71-butyric acid methyl ester (PC71BM) photovoltaic cells. To this end, various P3HT₄₈₈₀₀-based rod-coil block copolymers having the coily blocks of polystyrene (PS), poly(methyl methacrylate) (PMMA), and poly(ethylene glycol) (PEG) were synthesized. The grazing incidence X-ray scattering, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) analyses proved that the dielectric coily blocks, which were excluded from the P3HT crystalline structure, accumulated on the crystals surface without decreasing the crystal quality and formed hairy crystals. The multi-thermal techniques facilitated stacking of the growth planes in π-π direction for the P3HT crystals, thereby, this dimension was improved from 5 to 27 nm for conventionally prepared BHJs to 53–265 nm for multi-thermally developed ones. The hydrophobic coily blocks were capable of neutralizing the influence of the PCBM molecules presence in the growth environment, which resulted in the larger P3HT crystals in a similar condition. By switching the conventional spin coating approach to the cycling, aging, and seeding methods, the P3HT crystals and the PCBM clusters were gradually coarsened and the respective d-spacings decreased. This trend enhanced the hole mobility (=8.8×10⁻⁵ cm²/Vs), electron mobility (=2.5×10⁻³ cm²/Vs), short circuit current density (J_sc=12.02 mA/cm²), fill factor (FF=69%), and power conversion efficiency (PCE=4.39%) up to the maximum values for seeding approach. Moreover, the higher percentages of face-on orientation were detected in the BHJs with lower d-spacings in the hexyl side chain direction. Hairy P3HT₄₈₈₀₀-b-PS crystals developed by seeding method possessed the highest face-on orientation (~5.5%).