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Synergistic optimization of donor-acceptor blend morphologyis a hurdle in the path of realizing efficient non-fullerene small-molecule organic solar cells (NFSM-OSCs) due to the anisotropic conjugated backbones of both donor and acceptor. Therefore, developing a facile molecular design strategy to effectively regulate the crystalline properties of photoactive materials, and thus, enable the optimization of blend morphology is of vital importance. In this study, a new donor molecule B1, comprising phenyl-substituted benzodithiophene (BDT) central unit, exhibits strong interaction with the non-fullerene acceptor BO-4Cl in comparison with its corresponding thiophene-substituted BDT-based material, BTR. As a result, the B1 is affected and induced from an edge-on to a face-on orientation by the acceptor, while the BTR and the acceptor behave individually for the similar molecular orientation in pristine and blend films according to grazing incidence wide angle X-ray scattering results. It means the donor-acceptor blend morphology is synergistically optimized in the B1 system, and the B1:BO-4Cl-based devices achieve an outstanding power conversion efficiency (PCE) of 15.3%, further certified to be 15.1% by the National Institute of Metrology, China. Our results demonstrate a simple and effective strategy to improve the crystalline properties of the donor molecule as well as synergistically optimize the morphology of the all-small-molecule system, leading to the high-performance NFSM-OSCs.

Developing indium-tin-oxide (ITO)-free flexible organic photovoltaics (OPVs) with upscaling capacity is of great significance for practical applications of OPVs. Unfortunately, the efficiencies of the corresponding devices lag far behind those of ITO-based rigid small-area counterparts. To address this issue, an advanced device configuration is designed and fabricated featuring a top-illuminated structure with ultrathin Ag as the transparent electrode. First, a conjugated polyelectrolyte layer, i.e., PCP-Li, is inserted to effectively connect the bottom Ag anode and the hole transport layer, achieving good photon to electron conversion. Second, charge collecting grids are deposited to suppress the increased resistance loss with the upscaling of the device area, realizing almost full retention of device efficiency from 0.06 to 1 cm

With the purpose of improving the backbone planarity and thus the charge transport property of the wide-band-gap ester-modified polymer, the covalent and noncovalent (F···S conformational lock) bac...

Two conjugated polymers (PBTCO-TT and PBTCO-T), differing only in their conjugated backbones with thiophene (T) units in the latter and thieno[3,2-b]thiophene (TT) units in the former, were synthesized and applied in non-fullerene (NF) polymer solar cells (PSCs). The two polymers displayed similar absorption profiles in solutions and films at room temperature, but PBTCO-TT in solution showed a stronger temperature-dependent aggregation than PBTCO-T. Cyclic voltammetry and density functional calculations confirmed similar molecular energy levels for the two polymers (HOMO/LUMO of −5.41/−3.56 eV for PBTCO-TT and −5.43/−3.55 eV for PBTCO-T). After blending each of these polymers with a NF ITIC acceptor, the resulting PBTCO-TT:ITIC film showed a significantly greater surface roughness and stronger aggregation than the resulting PBTCO-T:ITIC film. In NF PSCs, the PBTCO-TT:ITIC-based PSC only gave a PCE of 5.31%, with a VOC of 0.881 V, JSC of 13.01 mA cm−2 and FF of 46.31%, while the PBTCO-T:ITIC-based PSC showed a significantly higher PCE of 10.40% with imultaneous improvement of the VOC to 0.959 V, of the JSC to 16.21 mA cm−2 and of the FF to 66.89%.

The innovation of photoactive layer materials is crucial for improving the power conversion efficiency (PCE) of polymer solar cells (PSCs). Herein, we report two polymer donors (PBTN-o and PBTN-p), which only differ in alkyl chains substituted at sites (6,7- or 5,8-) of the naphtho[2,3-c]thiophene-4,9-dione (NTD) unit. The single crystals of both NTD monomers demonstrate that NTD with alkyl chains at the 6,7-sites has a planar NTD skeleton, and surprisingly, NTD with alkyl chains at the 5,8-sites produces a bent NTD skeleton. The bent NTD-based polymer (PBTN-p) exhibits a more twisted conjugated backbone than PBTN-o. Our comparative studies show that PBTN-p possesses suitable aggregation properties that can optimize the photoactive layer morphology in NF PSCs. In PSCs, the optimal PBTN-o:BO-4Cl-based device shows a PCE of 11.85% with a VOC of 0.84 V, JSC of 22.41 mA cm−2, and FF of 0.63. In contrast, the optimal PBTN-p:BO-4Cl-based device exhibits a better PCE of 14.10% with the same VOC of 0.84 V, and an enhanced JSC of 24.67 mA cm−2 and FF of 0.68. This work provides a new insight into BHJ morphology optimization by side chain induced polymer main chain twisting in PSCs.

Interfacial engineering of electrode modification has proved to be an effective approach for improving the power conversion efficiency (PCE) of organic solar cells (OSCs). However, compared to the advances in active layers, the study of interfacial modification is seriously lagging and the contribution of electrode modification to PCE enhancement is marginalized. Herein, we synthesized a series of polynuclear metal-oxo clusters (PMCs) with gradually varied chemical compositions and photoelectronic properties, by which an efficient and stable hole extraction layer was developed to enhance OSC efficiency. The PCE of the OSC modified by PMC-4 was improved from 15.7% to 16.3% as compared to the PEDOT:PSS device. Moreover, PMC-4 can be fabricated through solution processing without any post-treatment and the corresponding device shows improved long-term stability. As revealed for the first time, the strong oxidizing property of PMC can induce formation of an inorganic–organic electron transfer complex with a barrier-free interface for efficient hole extraction. Furthermore, experimental data and theoretical calculation results reveal that the molecular polarization of mixed-addenda PMCs can enhance the capacitance at the AIL/active layer interfaces. As a result, the mixed-addenda PMCs can be processed via blade-coating to make a large-area OSC of 1 cm2 and a certified PCE of 14.3% was achieved.

Ruddlesden-Popper perovskite films deposited with different methods show very diverse phase segregation and composition. When DMSO is used as solvent, the conventional method based on spin-coating and annealing produces very poor devices, whereas the vacuum-assisted method proposed here allows obtaining devices with efficiency up to 14.14%. The conventional method gives rise to a three-dimensional (3D)-like phase on the top of the film but dominant n = 2 phase with large domains (∼40 μm) at the bottom of the film. These n = 2 domains are oriented with their inorganic slabs parallel to the substrate and inhibit the charge transport in the vertical direction. Consequently, severe monomolecular and bimolecular charge recombination occurs in the solar cells. Conversely, the vacuum-assisted method yields films with a 3D-like phase dominant throughout their entire thickness and only a small amount of n ≤ 2 domains of limited dimensions (∼3 μm) at the bottom, which facilitate charge transport and reduce charge recombination.

In order to meet the requirements for making organic solar cells (OSCs) through solution printing techniques, great efforts have been devoted into developing high performance OSCs with relatively thicker active layers. In this work, a thick-film (300 nm) ternary OSC with a power conversion efficiency of 14.3% is fabricated by introducing phenyl-C61-butyric-acid-methyl ester (PC61BM) into a PBDB-T-2Cl:BTP-4F host blend. The addition of PC61BM is found to be helpful for improving the hole and electron mobilities, and thus facilitates charge transport as well as suppresses charge recombination in the active layers, leading to the improved efficiencies of OSCs with relatively thicker active layers. Our results demonstrate the feasibility of employing fullerene derivative PC61BM to construct a high-efficiency thick-film ternary device, which would promote the development of thick layer ternary OSCs to fulfill the requirements of future roll to roll production.

Manufacturing large-area devices through a low-cost and large batch printing technique is the key to the commercialization of organic solar cells (OSCs). However, the lack of printable anode interlayer (AIL) materials severely impedes the development of high-efficiency printed OSCs. Herein, we synthesize three p-type self-doped conjugated polyelectrolytes (CPEs), namely, PCP-B, PCP-2B, and PCP-3B, as printable AIL materials for fabricating high-performance and large-area OSCs. By increasing the number of benzene units in the polymer backbone, the work function of the CPEs was enhanced from 4.57 to 5.01 eV, and the optical transparency was also improved because of the enlarged polymer band gap. The improved photoelectronic properties as well as a good film-forming capacity make the PCP-3B an ideal AIL material to be processed by the printing technique. By using PCP-3B, a 1 cm2 printed device was fabricated in which all the functional layers, including the AIL, active layer, and cathode interlayer were processed by blade-coating, achieving a power conversion efficiency (PCE) of 9.67%. The PCE belongs to the highest efficiency at present for printable large-area OSCs, showing a promising prospect for the OSC mass production.

Uncertainties exist and affect the actual port production. For example, at the beginning of 2020, the sudden outbreak of COVID-19 seriously affected terminal production and increased the short-term pressure of handling at container terminals. Consequently, a large number of containers were stacked at terminals, and the problem of terminal congestion became more serious. To solve the congestion problem of container terminals and ensure the priority dispatch of emergency materials, this study uses the optimized arrival patterns of external trucks and a priority dispatch strategy for emergency materials to establish a bilevel optimization model for container terminals and proposes a chaotic genetic algorithm based on logistic mapping as a solution. Through numerical experiments, the algorithm proposed in this study was compared with the genetic algorithm and adaptive genetic algorithm. The experimental results show that the model and algorithm proposed in this study can effectively reduce the total cost of containers in a terminal while ensuring the priority dispatch of emergency materials, reducing the overlapping part of the time window, optimizing the arrival mode of external trucks, and reducing the waiting time of external trucks, effectively alleviating the terminal congestion problem. [ABSTRACT FROM AUTHOR] Copyright of Discrete Dynamics in Nature & Society is the property of Hindawi Limited and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of electrode interlayers for hole extraction is a great challenge in the field of organic solar cells (OSCs). At present, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is the only solution-processed anode interlayer (AIL) that can be used to achieve power conversion efficiencies (PCEs) over 15% in OSC devices, even though there are several well-known drawbacks in practical applications of PEDOT:PSS. Herein, we use an inorganic molecular cluster (IMC) as the AIL for making highly efficient and large-area OSCs. The IMC possesses several advantages in serving as the AIL, such as neutral pH, excellent optical transmittance, high work function, good film-forming properties, and low cost. OSCs using the IMC can achieve a high PCE of 13.38%, which is superior to the PCE of the PEDOT:PSS device. This is among the few examples of OSC devices with solution-processed and pH neutral AILs showing higher PCE than PEDOT:PSS devices. Ultraviolet photoelectron spectroscopy and electron spin resonance results indicate the formation of inorganic-organic heterojunction, which is crucial for efficient hole extraction. More importantly, the IMC is compatible with printing processing. Using a blade-coated IMC film, we fabricated a large-area OSC of 1 cm

Recent works demonstrate that polyelectrolytes as a hole transport layer (HTL) offers superior performance in Ruddlesden-Popper perovskite solar cells (RPPSCs) compared to poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The factors contributing to such improvement need to be systematically investigated. To achieve this, we have systematically investigated how the two HTLs affect the morphology, crystallinity, and orientation of the Ruddlesden-Popper perovskite (RPP) films as well as the charge extraction of the RPPSCs. PEDOT:PSS as a HTL leads to RPP films of low crystallinity and with a number of large pinholes. These factors lead to poor charge carrier extraction and significant charge recombination in the RPPSCs. Conversely, a PCP-Na HTL gives rise to highly crystalline and pinhole-free RPPSC films. Moreover, a PCP-Na HTL provides a better energy alignment at the perovskite/HTL interface because of its higher work function compared to PEDOT:PSS. Consequently, devices using PCP-Na as HTLs are more efficient in extracting charge carriers.

Conjugated polymers (P3TE-C8 and P3TE-C12) with two different side chains based on thienyl-substituted benzodithiophene and dicarboxylic ester terthiophene were synthesized and applied in non-fullerene polymer solar cells (PSCs). Detailed studies revealed that the length of side chains in conjugated polymers showed a weak influence on their optical bandgaps and electrochemical properties, but a strong influence on their aggregation behaviors in solution, films, bulk heterojunction morphologies and photovoltaic performances. Among PSC devices, the P3TE-C8:ITIC-based device showed a PCE of 5.49%, a VOC of 0.814 V, JSC of 12.86 mA cm−2 and FF of 52.48%, while the P3TE-C12:ITIC-based device exhibited a higher PCE of 7.64%, with simultaneously improved photovoltaic parameters of VOC of 0.906 V, JSC of 14.20 mA cm−2 and FF of 59.36%. This work demonstrates that the reduction aggregation in conjugated polymers via changing the length of side chains is an effective method to improve PSC performances.

Summary Currently, most cathode interlayer (CIL) materials for organic solar cells (OSCs) cannot be processed by printing techniques, which severely limits their use in practical productions. Herein, we report a naphthalene diimide (NDI)-based small-molecular compound (N,N-dimethylamino)propyl naphthalene diimide (NDI-N) as printable CIL for OSCs. NDI-N exhibits a unique advantage that combines the merits of high crystallinity and good film-forming property in one material, endowing the semiconductor with excellent electron-transport properties and good processability. By using the NDI-N as CIL, a high power-conversion efficiency (PCE) of 13.9% was achieved in a PBDB-T-2F:IT-4F-based OSC device. More importantly, a large-area OSC device of 1 cm2 was fabricated by using the blade-coated NDI-N CIL and an outstanding PCE of 13.2% was achieved, which represents the highest efficiency of large-area OSCs. The results in this work may pave the way for low-cost and mass production of OSCs.

Conjugated polymers (CPs) as interfacial layer materials have played a crucial role in improving the power conversion efficiency (PCE) of organic solar cells (OSCs). Sulfonic acid-functionalized fl...

Revealing the charge generation is a crucial step to understand the organic photovoltaics. Recent development in non-fullerene organic solar cells (OSCs) indicates efficient charge separation even ...

Immersed tunnel is an important part of the Hong Kong–Zhuhai–Macao Bridge (HZMB) project. In immersed tunnel floating, translation which includes straight and transverse movements is the main working mode. To decide the magnitude and direction of the towing force for each tug, a particle swarm-based translation control method is presented for non-power immersed tunnel element. A sort of linear weighted logarithmic function is exploited to avoid weak subgoals. In simulation, the particle swarm-based control method is evaluated and compared with traditional empirical method in the case of the HZMB project. Simulation results show that the presented method delivers performance improvement in terms of the enhanced surplus towing force.

In this work, we demonstrated an effective method to modulate the p-type self-doping effect as well as the molecular energy level of an anionic conjugated polymer, namely PCP-x (x = H, Li, Na, K, Cs) by changing the counterions, and hence developed a series of anode interlayer materials for nonfullerene organic solar cells (NF-OSCs). With the decreasing cation radius, self-doping effect of PCP-x can be enhanced and hence the work function (WF) of the PCP-x-modified anodes can be tuned from 4.78 to 5.11 eV. The photovoltaic performance of NF-OSCs based on J52–2F:IT-4F active layer was significantly affected by the WF of the anodes, and a PCE of 12.8% could be achieved by using the PCP-H-modified ITO anodes. Furthermore, the PCP-x-modified anodes were used to fabricate NF-OSCs with different active layers, including PBDTTT-E-T:IEICO and PBDB-T-2F:IT-4F. It was found that the energetic offsets between WF of the anodes and ionization potential (IP) of the donors should be controlled below 0.1 eV to minimize t...

Fabricating organic solar cells (OSCs) with a tandem structure has been considered an effective method to overcome the limited light absorption spectra of organic photovoltaic materials. Currently, the most efficient tandem OSCs are fabricated by adopting fullerene derivatives as acceptors. In this work, we designed a new non-fullerene acceptor with an optical band gap (Egopt) of 1.68 eV for the front subcells and optimized the phase-separation morphology of a fullerene-free active layer with an Egopt of 1.36 eV to fabricate the rear subcell. The two subcells show a low energy loss and high external quantum efficiency, and their photoresponse spectra are complementary. In addition, an interconnection layer (ICL) composed of ZnO and a pH-neutral self-doped conductive polymer, PCP-Na, with high light transmittance in the near-IR range was developed. From the highly optimized subcells and ICL, solution-processed fullerene-free tandem OSCs with an average power conversion efficiency (PCE) greater than 13% wer...

Container truck congestion is one of the key issues affecting the efficiency of container terminals. To alleviate the congestion of the container truck at the gate, the Truck Appointment System (TAS) has been employed at many container ports. Based on the existing TAS, a truck appointment multi-constrained scheduling model based on Mixed Integer Nonlinear Programming (MINLP) is established, which takes into account the related constraints of the appointment change cost, gate queuing cost, congestion time cost and idle emission cost in the morning and evening peak periods. Aiming at the lowest integrated operation cost of truck and port companies, a two-stage truck reservation scheduling algorithm is used to optimize the solution and obtain the best container truck scheduling scheme. The simulation results of small, medium and large scales show that multi-constrained TAS can better serve container truck and port companies and effectively reduce their comprehensive operating cost, compared with conventional TAS.

In polymer solar cells (PSCs), it is difficult for twisted conjugated polymers to achieve high power-conversion efficiency (PCE) as donors due to their low charge carrier mobilities and poor bulk heterojunction morphologies. In this work, a new twisted conjugated polymer (P3TCO-1) with excellent solubilities (above 30 mg mL-1 ) in common organic solvents at room temperature is reported. UV-visible absorption spectra and cyclic voltammetry indicate that P3TCO-1 has a wide optical bandgap of 1.90 eV and deep HOMO level of -5.39 eV. In binary PSCs, P3TCO-1:ITIC-based device shows a PCE of 10.11%, with JSC of 17.05 mA cm-2 and FF of 62.89%; P3TCO-1:PC71 BM-based device gives a PCE of 6.67% with JSC of 12.31 mA cm-2 and FF of 58.00%. When the two acceptors of ITIC and PC71 BM are combined, the twisted P3TCO-1-based ternary PSCs exhibit a significantly boosted PCE of up to 11.41%, with a simultaneously improved JSC of 18.16 mA cm-2 and FF of 66.78%. These results can guide the improvement of PCE for twisted conjugated polymer-based PSCs.

Manufacturing large-area devices through a low-cost and large batch printing technique is the key to the commercialization of organic solar cells (OSCs). However, the lack of printable anode interlayer (AIL) materials severely impedes the development of high-efficiency printed OSCs. Herein, we synthesize three p-type self-doped conjugated polyelectrolytes (CPEs), namely, PCP-B, PCP-2B, and PCP-3B, as printable AIL materials for fabricating high-performance and large-area OSCs. By increasing the number of benzene units in the polymer backbone, the work function of the CPEs was enhanced from 4.57 to 5.01 eV, and the optical transparency was also improved because of the enlarged polymer band gap. The improved photoelectronic properties as well as a good film-forming capacity make the PCP-3B an ideal AIL material to be processed by the printing technique. By using PCP-3B, a 1 cm

Broadening the optical absorption of organic photovoltaic (OPV) materials by enhancing the intramolecular push-pull effect is a general and effective method to improve the power conversion efficiencies of OPV cells. However, in terms of the electron acceptors, the most common molecular design strategy of halogenation usually results in down-shifted molecular energy levels, thereby leading to decreased open-circuit voltages in the devices. Herein, we report a chlorinated non-fullerene acceptor, which exhibits an extended optical absorption and meanwhile displays a higher voltage than its fluorinated counterpart in the devices. This unexpected phenomenon can be ascribed to the reduced non-radiative energy loss (0.206 eV). Due to the simultaneously improved short-circuit current density and open-circuit voltage, a high efficiency of 16.5% is achieved. This study demonstrates that finely tuning the OPV materials to reduce the bandgap-voltage offset has great potential for boosting the efficiency., Halogenation has proved an effective strategy to improve the power conversion efficiencies of organic solar cells but it usually leads to lower open-circuit voltages. Here, Cui et al. unexpectedly obtain higher open-circuit voltages and achieve a record high PCE of 16.5% by chlorination.

A series of medium and wide band gap polymers with different backbones and side-chains were designed and synthesized as electron donors for fullerene-free polymer solar cells (PSCs). The relationship between the molecular structures of the polymer donors and the photovoltaic properties of the fullerene-free PSC devices was fully investigated. The optical band gaps and the energy levels of the polymers were modulated by the copolymerization of the benzodithiophene (BDT) unit with the various comonomers. Moreover, by incorporating alkylthio substituents, the highest occupied molecular orbital (HOMO) levels of the polymer donors were effectively reduced, and thus the open-circuit voltages (Voc) of the fullerene-free PSC devices were strongly improved. Simultaneously, the extinction coefficients of the polymers were also enhanced by introducing the alkylthio groups, which ensured sufficient light-harvesting capability. The exciton dissociation probability P(E,T) in the blend films of the alkylthio substituted...

Two p-type conjugated polymers with disparate optical and electronic properties, PB3T and PB2T, were developed and applied in fullerene-free polymer solar cells (PSCs). The photovoltaic performance of the PB3T-based PSC device processed by anisole achieved a high power conversion efficiency of 11.9% with a Jsc of 18.8 mA cm−2 and Voc of 1.00 V.

Two twisted terrylene diimides (TDIs), namely TDI2 and BTDI3, have been designed and synthesized. In comparison to monomeric TDI, their molecular geometries and optoelectronic properties have been systematically investigated. BTDI3, with a highly twisted 3D geometry, shows the best light-absorbing capability in the range of 500–700 nm and a suitable LUMO level. Simultaneously, a preliminary exploration of their photovoltaic performances was carried out. The optimized device based on PBDT-TS1/BTDI3 produces a power conversion efficiency (PCE) of 3.64%, demonstrating the potential of terrylene dyes in the photovoltaics field.

A series of conjugated polymers based on PFS derivatives with π-conjugated 5-(9H-fluoren-2-yl)-2,2′-bithiophene (fluorene-alt-bithiophene) backbones, namely PFS-3C, PFS-4C and PFS-6C, were synthesized for their use as the anode interfacial layers (AILs) in the efficient fullerene-free polymer solar cells (PSCs). Alkyl sulfonate pendants with different lengths of alkyl side chains were introduced in the three polymers in order to investigate the effect of the alkyl chain length on the anode modification. The obtained three polymers exhibited similar absorption bands and energy levels, indicating that changing the length of the alkyl side chains did not affect the optoelectronic properties of the conjugated polymers. Based on the PBDB-T:ITIC active layer, we fabricated the fullerene-free PSCs using the three polymers as the AILs. The superior performance of the fullerene-free PSC device was achieved when PFS-4C was used as the AIL, showing a power conversion efficiency (PCE) of 10.54%. The high performance of the PFS-4C-modified device could be ascribed to the high transmittance, suitable work-function (WF) and smooth surface of PFS-4C. To the best of our knowledge, the PCE obtained in the PFS-4C-modified device is among the highest PCE values in the fullerene-free PSCs at present. These results demonstrate that the PFS derivatives are promising candidates in serving as the AIL materials for high-performance fullerene-free PSCs.

Three pH neutral conjugated polymers based on thiophene and benzene derivatives, namely PCP-Na, PCF-Na, and PFS-Na, were designed and synthesized. In the three polymers, PCP-Na exhibited a self-doping effect in aqueous solution, and the thin film of PCP-Na demonstrated a high electrical conductivity of 1.66 × 10–3 S/cm and a deep HOMO level of −5.22 eV; these properties make it an ideal anode interfacial layer (AIL) material in polymer solar cells (PSCs). The single-junction PSC modified with PCP-Na AIL showed a PCE of 9.89%, which is comparable to that of the PEDOT:PSS-modified device (PCE = 9.53%). Notably, PCP-Na AIL exhibited excellent thickness insensitivity in fabricating PSC devices; i.e., the PSC devices with very thick PCP-Na interlayers over 300 nm still demonstrated a high fill factor over 70%, indicating the PCP-Na layer has excellent charge collection and transport properties. Furthermore, the homo-tandem PSC device was fabricated using a new connecting interlayer, which consists of PCP-Na as...

Currently, solution-processed MoO

Alkylthio groups have received much attention in the polymer community for their molecular design applications in polymer solar cells. In this work, alkylthio substitution on the conjugated thiophene side chains in benzodithiophene (BDT) and benzodithiophenedione (BDD)-based photovoltaic polymer was used to improve the extinction coefficient. The introduction of alkylthio groups into the polymer increased its extinction coefficient while the HOMO levels, bandgaps, and absorption bands remained the same. Thus, the short circuit current density (Jsc ) and the efficiency of the device were much better than those of the control device. Thus, introducing the alkylthio functional group in polymer is an effective method to tune the extinction coefficient of photovoltaic polymer. This provides a new path to improve photovoltaic performance without increasing active layer thickness, which will be very helpful to design advanced photovoltaic materials for high photovoltaic performance.

Two wide band gap (WBG) polymers based on thiophene-thiazolothiazole (TTz) units, PBT-TTz and PBT-S-TTz, were synthesized. Both polymers showed absorption onsets at 635 nm in solid films. Although PBT-TTz and PBT-S-TTz are WBG materials with relatively narrow absorption spectra, they have great potential for constructing high-performance polymer solar cells (PSCs). By replacing the alkyl side chain of PBT-TTz with an alkylthiol side chain, the HOMO level of PBT-S-TTz was lowered to −5.45 eV. A PCE of 7.92% was then obtained in a single-junction PSC device based on a PBT-S-TTz:PC71BM active layer. Moreover, high-performance fullerene-free PSCs were fabricated using these polymers and a high PCE of 8.22% was achieved. This work demonstrates that TTz-based polymers PBT-TTz and PBT-S-TTz are promising candidates as efficient WBG polymers for constructing high-performance PSC devices.

The fine alignment of molecular energy levels can efficiently enhance the open-circuit voltage (VOC) and improve the photovoltaic performance of polymer solar cells (PSCs). In this work, a novel polythiophene derivative donor with a low HOMO level of −5.6 eV was synthesized by copolymerizing carboxylate- and fluorine-substituted thiophene alternately. The introduction of fluorine downshifted the HOMO level of the polymer. On the other hand, a methyl-end-capped ITIC derivative, with elevated HOMO and LUMO levels, was selected as the acceptor in the pursuit of a higher VOC. A best power conversion efficiency (PCE) of 6.6% with an extremely high VOC of 1.13 V can be obtained after careful morphology optimization. Besides, an unprecedented energy loss of 0.46 eV is seen in this device, which is comparable to perovskite solar cells and has been rarely achieved before in bulk heterojunction PSCs.

A novel polymer-solar-cell architecture using the conjugated polymer PFS as both the anode and cathode interlayers is constructed, and a high power conversion efficiency of 9.48% is achieved using the corresponding photovoltaic device.

In automated logistics systems, travel time uncertainty can severely affect automated guided vehicle (AGV) conflict and path planning. Insight is required into how travel time uncertainty affects catch-up conflict, the main AGV conflict in one-way road networks. Under normal circumstances, the probability formula for catch-up conflict is deduced based on an analysis of AGV catch-up conflict. The vertex, monotonicity, and symmetry of catch-up conflict probabilities are developed, for symmetrical AGV travel time distribution densities. Adynamic adjustment method based on conflict probability for AGVs is designed. The probability features of catch-up conflicts and the performance of the associated dynamic adjustment are simulated and validated for AGVs at an automated container terminal. The simulation results show that the impact analysis of travel time uncertainty on AGV catch-up conflict is correct, and the dynamic adjustment is effective. info:eu-repo/semantics/publishedVersion

In this contribution, a novel cathode interlayer material (NDIO) based on naphthalene diimide was successfully prepared by a facile two-step reaction from commercially available compounds. NDIO exhibited excellent water solubility, high transparency in the visible light region, and well-matched molecular energy levels. By incorporating this novel water processed cathode interlayer, a high power conversion efficiency of 9.51% was recorded in PBDT-TS1/PC71BM-based polymer photovoltaic cells (PPCs), and the value is nearly 2-fold the device efficiency of PPCs without the cathode interlayer. More importantly, the insertion of the NDIO interlayer promotes the device efficiency of polymer/polymer photovoltaic cells based on PBDTTT-EFT/N2200 from 3.23% up to 5.77%. The successful applications in both polymer/PCBM and polymer/polymer blend-based inverted PPCs make NDIO a promising cathode interlayer for realizing aqueous processed polymer photovoltaic cells with high performance.

Nonlinear optical (NLO) crystal K 3 B 6 O 10 Br with the size of 27×29 ×14 mm 3 was successfully grown by top seeded solution growth (TSSG) technique. Its second harmonic generation (SHG) coefficients were determined by Maker fringe method as: d 22 =1.23±0.01 pm/V and d 33 =0.43±0.01 pm/V. Its linear electro-optical (EO) coefficient γ 22 =0.81±0.06 pm/V, which is usually employed in transverse modulation, was measured with polarimetric method.

With the rapid advance of organic photovoltaic materials, the energy level structure, active layer morphology, and fabrication procedure of organic solar cells (OSCs) are changed significantly. Thus, the photoelectronic properties of many traditional electrode interlayers have become unsuitable for modifying new active layers; this limits the further enhancement in OSC efficiencies. Herein, a new design strategy of tailoring the end-capping unit, ITIC, to develop a cathode interlayer (CIL) material for achieving high power conversion efficiency (PCE) in OSCs is demonstrated. The excellent electron accepting capacity, suitable energy level, and good film-forming ability endow the S-3 molecule with an outstanding electron extraction property. A device with S-3 shows a PCE of 16.6%, which is among the top values in the field of OSCs. More importantly, it is demonstrated that the electrostatic potential difference between the CIL molecule and the polymer donor plays a crucial role in promoting exciton dissociation at the CIL/active layer interface, contributing to additional charge generation; this is crucial for enhancement of the current density. The results of this work not only develop a new design strategy for high-performance CIL, but also demonstrate a reliable approach of density functional theory (DFT) calculation to predict the effect of the CIL chemical structure on exciton dissociation in OSCs.

Soybean Knowledge Base (SoyKB) is a comprehensive all-inclusive web resource for bridging the gap between soybean translational genomics and molecular breeding. It provides information for six entities including genes/proteins, microRNAs (miRNAs)/small interfering RNAs (sRNA), metabolites, single nucleotide polymorphisms (SNPs), and plant introduction lines and traits. It has a user-friendly web interface publicly available at http://soykb.org , which integrates and presents data in an intuitive manner to the soybean researchers, breeders, and consumers. It incorporates several informatics and analytical tools for integrating and merging various multi-omics datasets.

Soybean Knowledge Base (SoyKB) is a comprehensive all-inclusive web resource for bridging the gap between soybean translational genomics and molecular breeding. It provides information for six entities including genes/proteins, microRNAs (miRNAs)/small interfering RNAs (sRNA), metabolites, single nucleotide polymorphisms (SNPs), and plant introduction lines and traits. It has a user-friendly web interface publicly available at http://soykb.org , which integrates and presents data in an intuitive manner to the soybean researchers, breeders, and consumers. It incorporates several informatics and analytical tools for integrating and merging various multi-omics datasets.

Postgrowth rapid thermal annealing (RTA) was used to modify the optical properties of self-assembled InAs quantum dots (QDs) embedded in a photonic crystal nanocavity. Compared with the reference QDs in the unpatterned regions, it was found that the effect of RTA on the luminescence blueshift of QDs embedded in the nanocavities is similar to that from the unpatterned regions. However, InAs QDs in nanocavities exhibit an anomalous variation of luminescent linewidth during the course of RTA. This could be attributed to the deterioration of InAs QDs at the edge of photonic crystal air holes at high annealing temperatures. The stable position of cavity modes during the RTA temperatures shows the RTA technique could be applied to tune the spectral coupling of QDs/cavities when the QD spectra are on the red side of a cavity mode.

Water-soluble, meta- and para-linked poly(arylene ethynylene)s containing L-aspartic acid-functionalized fluorene units (P1 and P2) and their model compounds (M1 and M2) have been synthesized, and their photophysical properties and fluorescent sensing properties were investigated in aqueous solution. P1 and M1 with the meta-linkage show blue-shifted absorption and emission spectra, and decreased photoluminescence quantum yields compared with those of P2 and M2 with para-linkage. Their absorption and fluorescence spectra are pH dependent perhaps due to the aggregation of the polymer chains at low pH values. In buffer solutions, both polymers and their model compounds exhibit the excellent selectivity and sensitivity to Hg2+ over other common metal ions. Furthermore, the quenching constant and detection limit of P1 are determined to be 1.04 x 10(7) M-1 and 10 nM, and show the higher sensitivity compared to P2. Further comparison of their model compounds reveal that the sensitivity and quenching efficiency of M1 is also higher than that of M2, indicating that the meta-linkage pattern plays a key role in improving their Hg2+ ion sensing properties. In addition, both meta- and para-linked polymers exhibit the higher quenching efficiency than their model compounds due to the amplified fluorescence response of conjugated polymer. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

A novel conjugated cationic polyfluorene containing aminated tetraphenylethene (ATPE) unit is developed as a sensitive and selective fluorescence probe for heparin detection based on the combination of aggregation-induced emissive property of the ATPE units and the FRET process from the blue-emissive polyfluorene segments to the yellow-emissive ATPE units. The addition of anionic heparin will lead to the formation of heparin/polymer complexes, and turn on the aggregation-induced yellow emission of the ATPE units. A good linear relationship is found between the yellow emission intensity of the ATPE units and the heparin concentrations with a limit of detection of 30 nM in aqueous buffer.