DR3TBDTT Based Ternary Blends Containing Conjugated Polymers： Crystallization Determines Morphology and Performance

How the conjugated polymers affect the crystallization of DR3TBDTT, in addition to the corresponding morphology and performance, is not well understood. In this work, the weakly crystalline polymer PTB7-Th and highly crystalline polymers of PCDTBT and P3HT were incorporated into DR3TBDTT：PC71BM system to investigate the variation of crystallization, morphology and performance. It is demonstrated that PTB7-Th is the most effective additive to improve the PCE value of DR3TBDTT：PC71BM to 5.7%, showing the nucleating agent reducing the crystallization correlation length （CCL） value of DR3TBDTT from 18.7 nm to 17.0 rim, in addition to the optimized morphology. In contrast, the PCDTBT and P3HT could induce the crystallization of DR3TBDTT, leading to much higher CCL value as well as obvious phase separation. Despite of energy level alignment, the crystallization of DR3TBDTT influenced by polymers determines the corresponding morphology of active layers and photovoltaic performance.

Phase behavior and interfacial properties of symmetric polymeric ternary blends A/B/AB

In this paper, the phase behavior and interracial properties of symmetric ternary polymeric blends A/B/AB are studied by dissipative particle dynamics （DPD） simulations. By using the structure factor and nematic order parameter, we carefully characterized the diversified phases and phase transitions, and established the phase diagram of such symmetric ternary blends. It can be generally divided into four regions： disordered phase （DIS） region at high temperature, ordered lameUar phase （LAM） region, bicontinuous microemulsion （BμE） channel and phase-separated phase （2P） region at low temperature with the increase of the total volume fractions of homopolymers φn, which shows good accordance with that in previous experimental and theoretical reports. Furthermore, we calculated the elastic constants of 2P and LAM phase, and discussed the transition mechanisms from 2P and LAM to BμE phase, respectively. The results show a direct relevance between the phase transitions and the change of interfacial properties. Finally, we also demonstrate that the B,uE channel becomes narrower in lower temperature caused by the temperature dependence of interfacial properties of ternary blends.

Manipulating active layer morphology of molecular donor/polymer acceptor based organic solar cells through ternary blends

The development of molecular donor/polymer acceptor blend(MD/PA)-type organic solar cells(OSCs) lags far behind other type OSCs. It is due to the large-size phase separation morphology of MD/PAblend, which results from the high crystallinity of molecular donors. In this article, to suppress the crystallinity of molecular donors, we use ternary blends to develop OSCs based on one polymer acceptor(P-BNBP-f BT) and two molecular donors(DR3 TBDTT and BTR) with similar chemical structures.The ternary OSC exhibits a power conversion efficiency(PCE) of 4.85%, which is higher than those of the binary OSCs(PCE=3.60% or 3.86%). To our best knowledge, it is the first report of ternary MD/PA-type OSCs and this PCE is among the highest for MD/PA-type OSCs reported so far. Compared with the binary blends, the ternary blend exhibits decreased crystalline size and improved face-on orientation of the donors. As a result, the ternary blend exhibits improved and balanced charge mobilities, suppressed charge recombination and increased donor/acceptor interfacial areas, which leads to the higher shortcircuit current density. These results suggest that using ternary blend is an effective strategy to manipulate active layer morphology and enhance photovoltaic performance of MD/PA-type OSCs.

Experimental Investigation on Macro Spray Characteristics of Octanol-Biodiesel-Diesel Ternary Fuel Blend

This study investigates the spray characteristics of ternary blends composed of octanol, biodiesel, and diesel fuel.Experiments are conducted using six materials to examine the variation in spray characteristic and to verify and compare a previously established spray tip penetration model with a modified model. The results show that the addition of OB100(30%of octanol, 70% of biodiesel) improves the spray characteristics of the fuel. Specifically, the addition of 10% or 20% of OB100 leads to a slight increase in the spray tip penetration, average spray cone angle, maximum spray width, and the spray area of the fuel blend;however, further addition of OB100 causes a corresponding decrease in these parameters. Based on previous research, this study uses kinematic viscosity instead of dynamic viscosity and density to modify the prediction model of spray tip penetration. The modified model exhibits a better fit quality and agreement with the experimental data,making it more suitable for predicting the spray tip penetration of fuel blends compared to the Hiroyasu-Arai model.

Ternary blend strategy in benzotriazole-based organic photovoltaics for indoor application

Organic photovoltaics(OPVs)suitable for application in indoor lighting environments can power a wide range of internet of things(Io T)related electronic devices.The ternary structure has huge advantages in improving the photovoltaic performance of OPVs,including broadening the light absorption,improving the charge transport,manipulating the energy loss(E_(loss))and so on.Herein,we use wide-bandgap photo-active materials,including the benzotriazole-based polymer donor(J52-F),chlorinated polymer donor(PM7)and A_(2)-A_1-D-A_1-A_(2)-structured acceptor(BTA3),to construct ternary OPVs for indoor light applications.Benefitting from the introduction of PM7 as the third component in J52-F:BTA3-based blend,a gratifying PCE of 20.04%with a high V_(OC)of 1.00 V can be obtained under the test conditions with an illumination of 300 lx from an LED lighting source with a color temperature of 3000 K.The excellent device performance is inseparable from the matched spectrum,enhanced light absorption and the reduced E_(loss),while the improved charge transport capability and suppression of carrier recombination also play an indelible role.Our work shows a potential material system to meet the requirement of devices applied under indoor light.Moreover,these findings demonstrate that designing multi-component OPVs is indeed a feasible way to further improve the performances of the photovoltaic energy conversion system for indoor applications.

Study of a ternary blend system for bulk heterojunction thin film solar cells

In this research, we report a bulk heterojunction（BHJ） solar cell consisting of a ternary blend system. Poly（3-hexylthiophene） P3 HT is used as a donor and [6,6]-phenyl C61-butyric acid methylester（PCBM） plays the role of acceptor whereas vanadyl 2,9,16,23-tetraphenoxy-29 H, 31H-phthalocyanine（VOPc Ph O） is selected as an ambipolar transport material. The materials are selected and assembled in such a fashion that the generated charge carriers could efficiently be transported rightwards within the blend. The organic BHJ solar cells consist of ITO/PEDOT：PSS/ternary BHJ blend/Al structure. The power conversion efficiencies of the ITO/ PEDOT：PSS/P3HT：PCBM/Al and ITO/PEDOT：PSS/P3HT：PCBM：VOPcPhO/Al solar cells are found to be 2.3% and 3.4%, respectively.

Highly efficient ternary organic solar cells with excellent open-circuit voltage and fill factor via precisely tuning molecular stacking and morphology

The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells(OSCs). To address this issue, a non-fullerene acceptor PhC6-IC-F with alkylbenzene side-chain, possessing optimized molecular stacking, complementary absorption spectra and forming a cascade energy level alignment in the PM6:BTP-eC9 blend, is introduced as guest acceptor to improve efficiency of ternary OSCs. The bulky phenyl in the side-chain can regulate crystallinity and optimizing phase separation between receptors in ternary blend films, resulting in the optimal phase separations in the ternary films. As a result, high efficiencies of 18.33% as photovoltaic layer are obtained for PhC6-IC-F-based ternary devices with excellent fill factor(FF) of 78.92%. Impressively, the ternary system produces a significantly improved open circuit voltage(V_(oc)) of 0.857 V compared with the binary device,contributing to the reduced density of trap states and suppressed non-radiative recombination result in lower energy loss. This work demonstrates an effective approach for adjusting the aggregation, molecular packing and fine phase separation morphology to increase V_(oc) and FF, paving the way toward high-efficiency OSCs.

Chlorinated Thiazole-Based Low-Cost Polymer Donors for High Efficiency Binary and Ternary Organic Solar Cells

In this work,novel D-A alternating polymers(PJ-1,PJ-2,and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual chlorination.These polymers could be obtained readily through a few concise synthesis steps.Among them,PJ-1 displayed desirable properties including energy levels,crystallinity,and charge transport capabilities.The binary and ternary organic solar cells(OSCs)fabricated based on PJ-1 displayed significant power conversion efficiency(PCE)of 15.02%and 19.12%,respectively,placing them among the highest reported for ternary OSCs.Notably,the PJ1-based devices also showcased one of the highest figure-of-merit values,indicating their promising potential for future applications.This study offers valuable insights and supports the development of costeffective and high-performance polymer donors for the generation of OSCs.

Solar cells based on the poly(N-vinylcarbazole):porphyrin:tris(8-hydroxyquinolinato) aluminium blend system

Organic solar cells based on poly（N-vinylcarbazole） （PVK）： porphyrin： tris （8-hydroxyquinolinato） aluminium （Alq3） blend p-n junction systems have been fabricated in this work. The roles of the different components in the blend system and of the amount of porphyrin have been investigated. The 5, 10, 15, 20-tetraphenylporphyrin （TPP） and 5, 10, 15, 20-tetra（o-chloro）phenylporphyrinato-copper （CuTC1PP） are used in the solar cells. The results show that TPP is better than CuTC1PP in enhancing the performance of PVK：Alq3 solar cells. When the weight ratio of PVK：TPP：Alq3 is 1：1.5：1, the best performance of solar cell is obtained. The open circuit voltage （Voc） is 0.87 V, and the short circuit current （Jsc） is 17.5 μA·cm-2. In the ternary bulk hereojunction system, the device may be regarded as a cascade of three devices of PVK：TPP, TPP：Alq3 and PVK：Alq3. PVK, TPP and Alq3 can improve the hole mobility, light absorption intensity and electron mobility of the ternary bulk hereojunction system, respectively.

Side-chain modification of polyethylene glycol on conjugated polymers for ternary blend all-polymer solar cells with efficiency up to 9.27%

With the rapid progress achieved by all-polymer solar cells(all-PSCs), wide-bandgap copolymers have attracted intensive attention for their unique advantage of constructing complementary absorption profiles with conventional narrow-bandgap copolymers. In this work, we designed and synthesized a wide bandgap ternary copolymer PEG-2% which has the benzodithiophene-alt-difluorobenzotriazole as the backbone and the polyethylene glycol(PEG) modified side chain. The PBTA-PEG-2%:N2200 can be processed with a non-chlorinated solvent of 2-methyl-tetrahydrofuran(MeTHF) for the binary all-PSC, which exhibits a moderate photovoltaic performance. In particular, the ternary all-PSCs that consisting an additional narrow bandgap polymer donor PTB7-Th can also be processed with MeTHF, resulting in an unprecedented power conversion efficiency(PCE)of 9.27%, and a high PCE of 8.05% can be achieved with active layer thickness of 240 nm, both of which are the highest values so far reported from all-PSCs. Detailed investigations revealed that the dramatically improved device performances are attributable to the well-extended absorption band in the photoactive layer. Hence,developing novel copolymers with tailored side chains, and introducing additional polymeric components, can broaden the horizon for high-performance all-PSCs.

Microstructure evolution of laser solid forming of Ti-Al-V ternary system alloys from blended elemental powders

Morphology evolution of prior β grains of laser solid forming （LSF） Ti-xAl-yV （x 11,y 20） alloys from blended elemental powders is investigated. The formation mechanism of grain morphology is revealed by incorporating columnar to equiaxed transition （CET） mechanism during solidification. The morphology of prior β grains of LSF Ti-6Al-yV changes from columnar to equiaxed grains with increasing element V content from 4 to 20 wt.-%. This agrees well with CET theoretical prediction. Likewise, the grain morphology of LSF Ti-xAl-2V from blended elemental powders changes from large columnar to small equiaxed with increasing Al content from 2 to 11 wt.-%. The macro-morphologies of LSF Ti-8Al-2V and Ti-11Al-2V from blended elemental powders do not agree with CET predictions. This is caused by the increased disturbance effects of mixing enthalpy with increasing Al content, generated in the alloying process of Ti, Al, and V in the molten pool.

The improved performance in the ternary bulk heterojunction solar cells

The ternary blend films have been fabricated via adding 4,4'-N,N'-dicarbazole-biphenyl(CBP,a hole transport material widely used in organic light emitting diodes) into the poly(3-hexylthiophene):[6,6]-phenyl C 61-butyric acid methyl ester(P3HT:PCBM).Despite the wide bandgap(3.1 eV) of the CBP,the solar cell utilizing the optimized P3HT:PCBM:CBP blend film showed an increase of 16% in power conversion efficiency and 25% in short-circuit current than the compared standard P3HT:PCBM blend film.This is attributed to the fact that the addition of the CBP could enhance the aggregation of the P3HT chains and thereby reduce the hole-electron recombination at the interface of P3HT and PCBM.We provide a simple,effective way to improve the performance of P3HT based bulk heterojunction solar cells.

Improved efficiency of ternary the blend polymer solar cells by doping a narrow band gap polymer material

A series of P3HT：PC71BM polymer solar cells （PSCs） with different PIDTDTQx doping concentrations were fabricated to in- vestigate the effect of the PIDTDTQx as a complementary electron donor on the performance of PSCs. The power conversion efficiency （PCE） of the optimized ternary blend PSCs （with 2 wt% PIDTDTQx） reached 3.87%, which is 28% higher than that of the PSCs based on P3HT：PCvlBM （control cells）. The short-circuit current density （J^c） was increased to 10.20 mA/cm2 compared with the control cells. The PCE improvement could be attributed to more photon harvest and charge carrier transport by appropriate doping PIDTDTQx. The energy transfer from P3HT to PIDTDTQx was demonstrated from the 650 nm emis- sion intensity decrease and the red-shifted emission peaks from 725 nm to 737 nm along with the increase of PIDTDTQx dop- ing concentrations.

Host-Guest Strategy Enabling Nonhalogenated Solvent Processing for High-Performance All-Polymer Hosted Solar Cells

The power conversion efficiencies(PCEs)of all-polymer solar cells(all-PSCs),usually processed from low-boiling-point and toxic sol-vents,have reached high values of 18%.However,poor miscibility and uncontrollable crystallinity in polymer blends lead to a nota-ble drop in the PCEs when using green solvents,limiting the practical development of all-PSCs.Herein,a third component(guest)BTO was employed to optimize the miscibility and enhance the crystallinity of PM6/PY2Se-F host film processed from green solvent toluene(TL),which can effectively suppress the excessive aggregation of PY2Se-F and facilitate a nano-scale interpenetrating net-work morphology for exciton dissociation and charge transport.As a result,TL-processed all-polymer hosted solar cells(all-PHSCs)exhibited an impressive PCE of 17.01%.Moreover,the strong molecular interaction between the host and guest molecules also en-hances the thermal stability of the devices.Our host-guest strategy provides a unique approach to developing high-efficiency and stable all-PHSCs processed from green solvents,paving the way for the industrial development of all-PHSCs.

Improving photovoltaic parameters of all-polymer solar cells through integrating two polymeric donors

The incorporation of an additional component into the bulk-heterojunction light-harvesting layer of polymer solar cells has been considered as an effective strategy to enhance photovoltaic performance.Here we demonstrated that the photovoltaic parameters of all-polymer solar cells could be enhanced upon replacing a certain ratio of electron-donating polymer PTz BI-o F with a widely used wide-bandgap polymer donor PM6.The photoluminescent characterizations confirmed the F?rster resonance energy transfer from incorporated PM6 to PTz BI-o F.Moreover,the combination of Fourier-transform photocurrent spectroscopy and electroluminescence external quantum efficiencies measurements demonstrated reduced non-radiative recombination energy loss upon the incorporation of PM6,resulting in a slightly enhanced open-circuit voltage of 0.88 V of the ternary cell regarding the binary PTz BI-o F:PFA1 device.The optimized ternary blend devices comprising of PTz BI-o F:PM6:PFA1 presented an impressively high power conversion efficiency of 16.3%,and the efficiency remains 15%on a device with an enlarged effective area of 1 cm^(2),demonstrating the great potential of these all-PSCs for potential applications.