P3HT Nanoparticles Research Articles

Solution-processed organic-inorganic hybrid material based on P3HT and SnS2 nanoparticles layers: Synthesis and properties

Sn-based nanocomposites attract extensive attention as a new generation of photoelectric hybrid materials due to their high photoelectric conversion efficiency. In this work we synthesized SnS2 nanoparticles by a hydrothermal method employing citric acid (capping agent) and performed a capping agent exchange by pyridine to improve their solution processing and final properties. We fabricated layers with pyridine-capped nanoparticles and poly(3-hexylthiophene-2,5-diyl) (P3HT), employing the classical partial film sequence of a solar cell (ITO/PEDOT:PSS/P3HT:Nps). We found a “coupling" between the nanoparticles and the polymer and highly ordered structures within the layers. The addition of nanoparticles improved the UV–vis absorption of P3HT and allowed the exploitation of the photoluminescence emission to promote extra charge carrier generation. Moreover, we found that SnS2_py nanoparticles form a nanoscopic mixture with the P3HT. Our pyridine-capped SnS2 nanoparticles are good candidates for fabricating hybrid materials, employing P3HT as the organic compound for application in polymeric-inorganic solar cells.

Efficient Multilayers Organic Solar Cells with Hybrid Interfacial Layer-based P3HT and CuO Nanoparticles

Organic solar cell (OSC) devices suffer from low power conversion efficiency (PCE) due to deep trap states that absorb photogenerated charges, act as recombination centers, and reduce charge collection. To further improve the PCE, an optimized hole transport layer (HTL) must be engineered for efficient hole transport and reduced deep trap states. A hybrid HTL consisting of organic and inorganic materials was formed using a combination of CuO nanoparticles (NPs) having an average size of 50 nm and poly(3-hexylthiophene) (P3HT). The hybrid HTL was used in the fabrication and characterization of an inverted OSC device structure. In consequence, the incorporation of CuO-NPs into the P3HT resulted in an increase of 8.66% in photocurrent density. Additionally, the PCE increased from 3.77 to 4.22% while the open circuit voltage (Voc) was maintained. The higher hole mobility obtained for the optimum device using the charge extraction by increasing voltage (CELIV) measurement was 8.47 × 10− 4 cm2 V− 1 s− 1. This highlights the potential of designing novel organic solar cells with inorganic nanoparticles, offering enhanced performance and efficiency.

Ultrafast Electron Transfer Dynamics of Organic Polymer Nanoparticles with Graphene Oxide.

We prepared organic polymer poly-3-hexylthiophene (p3ht) nanoparticles (NPs) and graphene oxide (GO)/reduced graphene oxide (RGO) composites p3ht NPs-GO/RGO by using the reprecipitation method. We demonstrated that GO/RGO could improve the ordering and planarity of p3ht chains as well as the formation of p3ht NPs, and confirmed the effects of GO/RGO on the fluorescence and carrier transport dynamics of p3ht NPs by using femtosecond fluorescence upconversion and transient absorption (TA) techniques. Ultrafast electron transfer (∼1 ps) between GO/RGO and p3ht NPs quenched the fluorescence of p3ht NPs, indicating excellent properties of p3ht NPs-GO/RGO as the charge transfer complexes. Efficient electron transfer may promote the applications of p3ht NPs-GO/RGO composites in organic polymer solar cells and photocatalysis. Moreover, RGO had stronger interfacial interactions and more matched conduction band energy levels with p3ht NPs than GO did, which implied that p3ht NPs-RGO might have greater application values than p3ht NPs-GO.

Graphene Nanosheets Stabilized by P3HT Nanoparticles for Printable Metal-Free Electrocatalysts for Oxygen Reduction

The development of metal-free electrocatalysts with efficient catalytic performance and long-term stability is highly desirable for fuel cell applications. In this study, a solution-processable graphene-based electrocatalyst for the oxygen reduction reaction (ORR) is developed using a facile liquid-phase exfoliation process. An aqueous dispersion of poly(3-hexylthiophene-2,5-diyl) (P3HT) nanoparticles is prepared via a simple miniemulsion process and used as a medium for graphite exfoliation, where the interfacial interaction between P3HT nanoparticles and graphene is utilized to simultaneously stabilize the exfoliated graphene flakes and induce efficient intermolecular charge transfer to accelerate the ORR. Neutron scattering with contrast variation was carried out to study the colloidal architecture of the produced dispersions and the interactions at the interface between graphene and P3HT nanoparticles. The nanoparticle-stabilized graphene (G/P3HT) dispersions were employed for printing of flexible conductive circuits (∼180 Ω sq–1) and fabrication of metal-free electrocatalyst layers for the ORR, which reduces O2 molecules to OH– ions via the highly efficient four-electron pathway and exhibits superior stability (∼97% retention after 10,000 cycles). This printable graphene electrocatalyst provides a breakthrough in green chemistry and advanced techniques for the fabrication of low-cost and sustainable fuel cells.

An Innovative Anode Interface Combination for Perovskite Solar Cells with Improved Efficiency, Stability, and Reproducibility

Rational design and engineering of top interface layers with combined properties of effective passivation, high thermal‐ and photo‐stability are effective methods to advance the commercialization of perovskite photovoltaics. Here, an innovative anode interface combination is developed based on alcohol‐dispersed poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) nanoparticles as the hole transport material and chlorobenzene‐dissolved trioctylphosphine oxide (TOPO) as the passivation agent. It is shown that instead of the commonly used 2D passivation ligands, TOPO‐passivated perovskite films exhibit greatly improved thermal stability. Furthermore, the passivation contributes to an enhanced carrier lifetime and reduced surface trap density, yielding an improvement in the quasi‐fermi‐level splitting of 57 meV. To maintain surface passivation during solution processing of further layers, it is necessary to develop a hole transport layer that can be processed from orthogonal solvents. P3HT nanoparticles formulated in alcoholic media fully meet this requirement, clearly benefitting from their high vertical conductivity and extremely low contact resistance with carbon electrodes. Based on this configuration, device efficiency of up to 18.4% is demonstrated for perovskite solar cells with fully solution‐processed carbon electrodes, along with significantly improved device stability and reproducibility.

A photoelectric effect integrated scaffold for the wireless regulation of nerve cellular behavior.

Electrical signals are a key factor to promote nerve cell neurogenesis. However, the traditionally used exogenous electrical stimulus mode requires additional equipment and complicated wiring, which is very inconvenient. To date, it has been challenging to provide electrical signals to nerve cells in a non-invasive and wireless controllable way, accompanied by the construction of a biomimetic cell microenvironment for supporting nerve cell survival and functional expression. Herein, a new concept of a light-powered oriented bioactive scaffold for remote and wireless electrical stimulation has been developed. By combining electrospinning and electrospraying, the highly oriented polycaprolactone (PCL) microfibrous scaffold with co-sprayed bioactive collagen and photoelectric poly-3-hexylthiophene nanoparticles (P3HT NPs) was obtained, named as PCL-P3HT-Col, which exhibits a considerable photoelectric effect and vital characteristics of the native nerve extracellular matrix. The results show that a photocurrent ranging from 20-80 pA was obtained by changing the light density of a 530 nm green light source. Further, the specific photoelectric conversion effect trigged by the P3HT NPs promotes the oriented elongation and up-regulation of neuronal characteristic factors in rat pheochromocytoma cells (PC12 cells), which is controlled by L-type voltage-gated calcium channel (L-VGCC) activity. This study provides new insights to engineer self-powered scaffolds towards the non-invasive and wireless-controlled stimulation mode of a variety of cells and tissues.

Disorder in P3HT Nanoparticles Probed by Optical Spectroscopy on P3HT-b-PEG Micelles.

We employ photoluminescence (PL) spectroscopy on individual nanoscale aggregates of the conjugated polymer poly(3-hexylthiophene), P3HT, at room temperature (RT) and at low temperature (LT) (1.5 K), to unravel different levels of structural and electronic disorder within P3HT nanoparticles. The aggregates are prepared by self-assembly of the block copolymer P3HT-block-poly(ethylene glycol) (P3HT-b-PEG) into micelles, with the P3HT aggregates constituting the micelles’ core. Irrespective of temperature, we find from the intensity ratio between the 0–1 and 0–0 peaks in the PL spectra that the P3HT aggregates are of H-type nature, as expected from π-stacked conjugated thiophene backbones. Moreover, the distributions of the PL peak ratios demonstrate a large variation of disorder between micelles (inter-aggregate disorder) and within individual aggregates (intra-aggregate disorder). Upon cooling from RT to LT, the PL spectra red-shift by 550 cm–1, and the energy of the (effective) carbon-bond stretch mode is reduced by 100 cm–1. These spectral changes indicate that the P3HT backbone in the P3HT-b-PEG copolymer does not fully planarize before aggregation at RT and that upon cooling, partial planarization occurs. This intra-chain torsional disorder is ultimately responsible for the intra- and inter-aggregate disorder. These findings are supported by temperature-dependent absorption spectra on thin P3HT films. The interplay between intra-chain, intra-aggregate, and inter-aggregate disorder is key for the bulk photophysical properties of nanoparticles based on conjugated polymers, for example, in hierarchical (super-) structures. Ultimately, these properties determine the usefulness of such structures in hybrid organic–inorganic materials, for example, in (bio-)sensing and optoelectronics applications.

Limits of Detection Based on the Four-Parameter Logistic Model for E. coli Determined using a Fluorescent-based Sensor


 
 
 
 Because of the huge number of outbreaks, bacterial infection is becoming more common, which is compounded by the rise of antibiotic resistance. These issues have warranted the development of sensitive detection and therapeutic devices. A fluorescence-based detection of the pathogen E. coli is previously developed using a mini-emulsion technique to create fluorescent/electroactive poly(3-hexylthiophene) P3HT nanoparticles (NPs) stabilized with CTAB or cetyltrimethylammonium bromide, a quaternary ammonium salt forming CTAB-P3HT NPs. Limits of detection for the bacterium based on fluorescence spectroscopy is 5 CFU/mL. The curve showed a sigmoidal calibration curve but was not modelled according to any of the sigmoidal models available. The aim of this study is to use the Four-Parameter Logistic Model to determine the LOD value more accurately. The modelling exercise gave values of the parameters a, d, Log EC50 and Hillslope representing the maximum and minimum responses, value that produces a 50% signal response, and a slope-like parameter (Hill coefficient) of -0.01427 (DF/F0), 0.6189 (DF/F0), 3.473 and 0.413, respectively. The LOD value was 30 CFU/mL with the 95% confidence interval from 13 to 64 CFU/mL. The usage of the 4Pl model in this study was successful, since it was able to represent the entire date curve. The correlation coefficient values of 0.986 indicated good fitting of the experimental data to the 4PL model. The 4PL model has been found to be a good model in fitting the calibration curve for the detection of E. coli.
 
 
 

Antimicrobial Activity of Cationic Poly(3-hexylthiophene) Nanoparticles Coupled with Dual Fluorescent and Electrochemical Sensing: Theragnostic Prospect.

Designing therapeutic and sensor materials to diagnose and eliminate bacterial infections remains a significant challenge for active theragnostic nanoprobes. In the present work, fluorescent/electroactive poly(3-hexylthiophene) P3HT nanoparticles (NPs) stabilized with quaternary ammonium salts using cetyltrimethylammonium bromide (CTAB), (CTAB-P3HT NPs) were prepared using a simple mini-emulsion method. The morphology, spectroscopic properties and electronic properties of CTAB-P3HT NPs were characterized by DLS, zeta potential, SEM, TEM, UV-vis spectrophotometry, fluorescence spectroscopy and electrochemical impedance spectroscopy (EIS). In an aqueous solution, CTAB-P3HT NPs were revealed to be uniformly sized, highly fluorescent and present a highly positively charged NP surface with good electroactivity. Dual detection was demonstrated as the binding of the bacteria to NPs could be observed by fluorescence quenching as well as by the changes in EIS. Binding of E. coli to CTAB-P3HT NPs was demonstrated and LODs of 5 CFU/mL and 250 CFU/mL were obtained by relying on the fluorescence spectroscopy and EIS, respectively. The antimicrobial activity of CTAB-P3HT NPs on bacteria and fungi was also studied under dark and nutritive conditions. An MIC and an MBC of 2.5 µg/mL were obtained with E. coli and with S. aureus, and of 0.312 µg/mL with C. albicans. Additionally a good biocompatibility toward normal human cells (WI38) was observed, which opens the way to their possible use as a therapeutic agent.

μSR Study with Light Irradiation of P3HT:ZnO Nanoparticles as Active Material of Hybrid Solar Cells

Recently, hybrid solar cell that consists of a combination of organic and inorganic materials offers promise in increasing efficiency. Combination of conjugated polymer of Poly (3-hexyl thiophene)/P3HT which has the highest hole mobility with inorganic materials which has high electron mobility, good physical and chemical stability of inorganic nanocrystals, shows a better performance of hybrid solar cells. We have conducted a measurement to investigate the charge carrier transport in active material of hybrid solar cells by using muon spin relaxation (μSR) with light irradiation. A bulk sample used in this study is hybrid organic-inorganic material consisting of regio-regular P3HT and ZnO nanoparticles. Longitudinal-field μSR measurements were performed in magnetic field ranging from 0 to 395 mT at temperature of 10 K, 15 K and 25 K. Based on μSR measurement with light irradiation, we found that for those temperatures, longitudinal field dependence of λ1 was proportional with C-H0.5 curve indicating three-dimensional inter-chain diffusion. We assume that light irradiation initiates the production of exciton that increases the number of charge carrier in the sample and transports not only along the chain of polymer (one-dimensional) but also perpendicular to other chain of polymer (three-dimensional). With light irradiation, the crossover temperature from one-dimensional to three-dimensional of regio-regular P3HT and ZnO nanoparticles bulk sample was obtained at lower temperature of 10 K compared to previous result at 25 K without light irradiation.

Elaboration of PCBM Coated P3HT Nanoparticles: Understanding the Shell Formation

Solvent displacement, or nanoprecipitation, is a well-known process to develop colloidal dispersions in water. Using two successive and selective nanoprecipitation steps, we developed a method to generate [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) shell on poly(3-hexylthiophene) (P3HT) core nanoparticles (P3HT@PCBM). We report herein on the understanding of the shell formation during this process. Using several techniques (dynamic light scattering, zeta-potential, photoluminescence), we evidenced that after the first solvent displacement with dimethyl sulfoxide (DMSO), the PCBM molecules still dissolved in the medium are already in close interaction with the P3HT nanoparticles (NP). Such proximity of the P3HT core with PCBM molecules in the DMSO dispersion explains why PCBM aggregates around the nanoparticles during the second solvent displacement with water. A fast electron transfer from P3HT to PCBM was identified by transient absorption spectroscopy, confirming the core-shell morphology even for low PCBM concentration. This study opens the route for the development of well-defined nano-objects dispersed in water for fabrication of organic photovoltaic devices with eco-friendly processes.

Charge carrier transport in blend of P3HT and ZnO nanoparticles at low temperature studied by µSR

Recently, hybrid solar cell, which is a combination of organic and inorganic material, has been developed to produce better performance especially in power conversion efficiency of solar cell. Organic material based on conjugated polymer such as Poly(3-hexylthiophene) (P3HT) attracted much attention because P3HT shows the highest hole mobility among the series of Poly(3-alkylthiophene). On the other hand, it is well known that ZnO nanoparticles are an inorganic material with high electron mobility that can be acted as electron acceptor to dissociate excitons formed in organic material. The existence of ZnO nanoparticles in active layer of solar cell will lead to dissociation of excitons in P3HT via rapid electron transfer to ZnO. To understand the mechanism of charge carrier transport in blend of P3HT and ZnO nanoparticles, we have been conducted an experiment using muon spin relaxation (µSR) at low temperature of 10 K with variation of longitudinal field from 2 to 395 mT. We also investigated the effect of light irradiation to the charge carrier transport in blend of P3HT and ZnO nanoparticles. Without light irradiation, it is clearly observed that depolarization rate (λ) was proportional to linier field of H-0.5, indicating one-dimensional intra-chain transport of charge carrier. With light irradiation, it is found that asymmetry data changed slightly indicating the trace of any changing of charge carrier transport to increase in the amount of exciton in samples causing by light irradiation.

In situ construction of conjugated polymer P3HT coupled hierarchical ZnO composite with Z-scheme enhanced visible-light photocatalytic activity

Conjugated polymer P3HT coupled with hierarchical ZnO (H-ZnO) photocatalysts were fabricated by a two-step solution method with assembling P3HT nanoparticles on the surface of H-ZnO micro-flowers. Optical properties revealed that the fabricated H-ZnO micro-flowers were rich in defects. The as-prepared P3HT@H-ZnO composite exhibited higher photocatalytic activity than H-ZnO for photocatalytic degradation of Rhodamine B (RhB) under visible light irradiation. The enhanced photocatalytic activity was attributed to the strengthened visible light absorption and the closely contacted interface between P3HT and H-ZnO. Based on the reactive species trapping experiments and band gap structure analysis, it can be identified that the effective separation and transfer of the photo-induced electron-hole pairs within the P3HT@H-ZnO composite follow a Z-scheme mechanism rather than type II heterojunction. The present work will provide a new insight to design Z-scheme photocatalysts with enhanced photocatalytic performance via metal-free polymers modification.

Conjugated Polymer Nanoparticle–Graphene Oxide Charge‐Transfer Complexes

AbstractThe game‐changing role of graphene oxide (GO) in tuning the excitonic behavior of conjugated polymer nanoparticles is described for the first time. This is demonstrated by using poly(3‐hexylthiophene) (P3HT) as a benchmark conjugated polymer and employing an in situ reprecipitation approach resulting in P3HT nanoparticles (P3HTNPs) with sizes of 50–100 nm in intimate contact with GO. During the self‐assembly process, GO changes the crystalline packing of P3HT chains in the forming P3HTNPs from H to H/J aggregates exhibiting exciton coupling constants as low as 2 meV, indicating favorable charge separation along the P3HT chains. Concomitantly, π–π interface interactions between the P3HTNPs and GO sheets are established resulting in the creation of P3HTNPs–GO charge‐transfer complexes whose energy bandgaps are lowered by up to 0.5 eV. Moreover, their optoelectronic properties, preestablished in the liquid phase, are retained when processed into thin films from the stable aqueous dispersions, thus eliminating the critical dependency on external processing parameters. These results can be transferred to other types of conjugated polymers. Combined with the possibility of employing water based “green” processing technologies, charge‐transfer complexes of conjugated polymer nanoparticles and GO open new pathways for the fabrication of improved optoelectronic thin film devices.

Morphology, photophysics and optoelectronics of P3HT nanoparticles and TiO2 nanorods composite

Morphology and photophysics of polymers are critical to the performance of organic optoelectronics. In this work, poly(3-thiophene) (P3HT) nanoparticles were successfully fabricated by the miniemulsion and reprecipitation methods. The P3HT nanoparticles demonstrated uniform distribution with the domain size of [Formula: see text][Formula: see text]40 nm. The photophysics of P3HT nanoparticles was investigated by absorption and steady-state and time-resolved PL spectroscopy. P3HT nanoparticles showed more ordered and longer conjugation length than pristine P3HT. At the same time, P3HT nanoparticles showed aggregate species which are favorable for interchain charge transfer. The organic/inorganic hybrid photodetectors based on P3HT and TiO2 nanorods were fabricated. The superior performance of the photodetector based on P3HT nanoparticle and TiO2 nanorods comes from the efficient charge transfer and large donor/acceptor interface.

Simultaneously Induced Self‐Assembly of Poly(3‐hexylthiophene) (P3HT) Nanowires and Thin‐Film Fabrication via Solution‐Floating Method on a Water Substrate

AbstractA single‐step fabrication of thin film of conjugated polymers (CPs) cannot be employed because inducement of self‐assembly of CPs and a thin‐film fabrication process are both required. This study introduces a simple and facile one‐pot strategy for fabricating uniform, large‐area organic semiconducting thin film without complex process. During the solvent evaporation of floated poly(3‐hexylthiophene) (P3HT) solution on water substrate, well‐dissolved P3HT chains are self‐assembled into 1D P3HT nanowires (NWs) with formation of thin film simultaneously. Through systematic transmission electron microscopy (TEM) experiments, this study also reveals for the first time the unique self‐assembly mechanism behind the formation of P3HT NWs from the incorporation of P3HT nanoparticles (NPs). In addition, highly uniform organic–inorganic hybrid thin films consisting of well‐defined P3HT/quantum dots (QDs) hybrid NWs can be created easily via a solution‐floating method by dropping P3HT and QDs dissolved solution. The floated P3HT NWs thin film on the surface of water can be easily transferred onto a Si wafer, bestowing advantages for the fabrication of a high‐performance organic field‐effect transistor device with a carrier mobility of 0.0856 cm2 V−1 s−1.

Poly(3-hexylthiophene) Nanoparticles Containing Thiophene-S,S-dioxide: Tuning of Dimensions, Optical and Redox Properties, and Charge Separation under Illumination.

We describe the preparation of poly(3-hexylthiophene-S,S-dioxide) nanoparticles using Rozen's reagent, HOF·CH3CN, either on poly(3-hexylthiophene) (P3HT) or on preformed P3HT nanoparticles (P3HT-NPs). In the latter case, core-shell nanoparticles (P3HT@PTDO-NPs) are formed, as confirmed by X-ray photoelectron spectroscopy measurements, indicating the presence of oxygen on the outer shell. The different preparation modalities lead to a fine-tuning of the chemical-physical properties of the nanoparticles. We show that absorption and photoluminescence features, electrochemical properties, size, and stability of colloidal solutions can be finely modulated by controlling the amount of oxygen present. Atomic force microscopy measurements on the nanoparticles obtained by a nanoprecipitation method from preoxidized P3HT (PTDO-NPs) display spherical morphology and dimensions down to 5 nm. Finally, Kelvin probe measurements show that the coexistence of p- and n-type charge carriers in all types of oxygenated nanoparticles makes them capable of generating and separating charge under illumination. Furthermore, in core-shell nanoparticles, the nanosegregation of the two materials, in different regions of the nanoparticles, allows a more efficient charge separation.

Addition of P3HT-grafted Silica nanoparticles improves bulk-heterojunction morphology in P3HT-PCBM blends.

We present molecular dynamics simulations of a ternary blend of P3HT, PCBM and P3HT-grafted silica nanoparticles (SiNP) for applications in polymer-based solar cells. Using coarse-grained models, we study the effect of SiNP on the spatial arrangement of PCBM in P3HT. Our results suggest that addition of SiNP not only alters the morphology of PCBM clusters but also improves the crystallinity of P3HT. We exploit the property of grafted SiNP to self-assemble into a variety of anisotropic structures and the tendency of PCBM to preferentially adhere to SiNP surface, due to favorable interactions, to achieve morphologies with desirable characteristics for the active layer, including domain size, crystallinity of P3HT, and elimination of isolated islands of PCBM. As the concentration of SiNP increases, the number of isolated PCBM molecules decreases, which in turn improves the crystallinity of P3HT domains. We also observe that by tuning the grafting parameters of SiNP, it is possible to achieve structures ranging from cylindrical to sheets to highly interconnected network of strings. The changes brought about by addition of SiNP shows a promising potential to improve the performance of these materials when used as active layers in organic photovoltaics.

Efficient photoinduced charge transfer in chemically-linked organic-metal Ag-P3HT nanocomposites

A novel nanocomposite of P3HT and Ag nanoparticles (Ag-P3HT) has been synthesized by laser ablation. The fluorescence wavelength of the nanocomposite can be tuned by varying the ablation duration. The steady-state emission maximum at 580 nm for pristine P3HT shows significant blueshift to wavelengths ranging from 520 to 550 nm for Ag-P3HT. NMR, FTIR and XPS spectroscopy confirm that chemical links are formed between P3HT and silver nanoparticles (NPs) in the nanocomposite. For the sample with an emission maximum at 530 nm, 1H NMR spectra indicate that 66% of the P3HT thiophene ring protons are replaced by Ag NPs. Time-resolved spectroscopy demonstrates that charge transfer efficiency increases for Ag-P3HT and this is attributed to the enhanced intimate interfacial contact between the chemically-bonded metal NPs and polymer chains. The synthetic route outlined provides a one-pot and green strategy for producing metal-organic polymeric materials, with controlled luminescence wavelengths and efficient photoinduced charge transfer that meet the requirement for developing high-performance organic light-emitting and photovoltaic devices.

Molecular Packing in Organic Solar Cell Materials: Insights from the Emission Line Shapes of P3HT/PCBM Polymer Blend Nanoparticles

Semiconducting polymer devices have seen tremendous progress in development of material and device designs, while device efficiencies have made substantial gains. Still, the effect of material morphology on the optoelectronic properties of semiconducting polymers is not completely understood even though these materials make up the active device layer. In this study we use computational methods to simulate different poly(3-hexylthiophene) (P3HT) morphologies, predict their emission spectra, and compare them to experimentally observed emission spectra for P3HT nanoparticles. We use published X-ray diffraction data on P3HT polymorphs to build the molecular models of nanodomains that differ in the side-chain packing. The atomic and electronic structures of both nanodomains are studied with the force field, Hartree–Fock, CIS, and density functional theory methods. The results confirm the coexistence of type I and II nanodomains, where the shift of the backbones in the same stack is determined by the differences in side-chain packing. Upon excitation, the polymer chains in type II domain are free to slide to their optimal arrangement in the stack, whereas in type I domain this sliding is hindered by the steric repulsion of the side chains and the chains are essentially constrained to keep the ground state geometry. These nanodomains, therefore, differ in their emission spectra: type I emission has a single 0–0 vibronic band, while type II demonstrates pronounced vibronic progression. In agreement with Frenkel exciton theory, splitting of the excited state depends on the longitudinal shift of the π-systems. However, we find that due to the constraints arising from P3HT being confined in nanosized particles, the type I nanodomain increasingly appears as an additional emitter that exhibits J-aggregate character. As a result, a pronounced vibronic structure appears as PCBM blending ratios increase, as opposed to the changes in emission profile due to a different degree of disorder present in weakly coupled H-aggregates. These findings are distinct from those made for bulk P3HT materials.