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Poly(epsilon-caprolactone)/polylactide blend (PCL/PLA) is an interesting biomaterial because PCL and PLA present good complementarity in their physical properties and biodegradability. However, the thermodynamic incompatibility between two component polymers restricts further applications of their blend. In this work, we used functionalized multiwalled carbon nanotube (MWCNT) to control the morphology of immiscible PCL/PLA blend. The ternary PCL/PLA/MWCNTs composites were hence prepared by melt mixing for the morphology and the properties investigation. It is interesting to find that the functionalized MWCNTs are selectively dispersed in the matrix PCL phase and on the interface between two polymer phases, leading to simultaneous occurrence of thermodynamically and kinetically driven compatibility. Those interface-localized MWCNTs prevent coalescence of the discrete domains and enhance the phase interfacial adhesion as well. As a result, the phase morphology of the ternary composites is improved remarkably in contrast to that of the blank PCL/PLA blend. Owing to that unique selective interface-localization and improved phase morphology, the ternary composites present far lower rheological and conductive percolation thresholds than those of the binary composites, and also present extraordinary mechanical properties even at very low loading levels of the MWCNTs. Therefore, the amphiphilic MWCNTs are believed to act as the reinforcements as well as the compatibilizer in the immiscible PCL/PLA blend.

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resulting in inefficient charge separation and collection. [7][8][9] However, recent progresses show quite steep climbing of power conversion efficiency (PCE) for all-PSCs, reaching a value over 10%, [10][11][12] under systematic optimization, leaving a large gap to be filled in understanding the mechanism of morphology evolution. Polymer blends that reach nanoscaled phase separation in organic photovoltaic (OPV) application have distinctive advantages. They are more suitable for printing fabrication because of their good filmforming ability and mechanical flexibility, prominent device stability, and readily tunable ink viscosity. [13][14][15][16][17] Such benefits make all-PSC unique in scalable OPV fabrication, which also leads to boosted interest in understanding and manipulating the morphology. Initiative efforts on all-PSC printing have been surveyed, showing PCEs way below device made by spin-coating. [16,18] The mystery lies in morphology control, of which BHJ thin film is typical nonequilibrium nature that film-drying kinetics dictates the final nanostructure composed of crystalline networks and mixed and phase-separated domains. [19][20][21] It has been shown that solar cells using polymer:non-fullerene acceptor blends processed by slot die printing have exceed 11% in PCE, [22][23][24][25][26][27][28] from which we think that fine-tuning of morphology in all-PSCs could reach a similar level once a All-polymer solar cells (all-PSCs) exhibit excellent stability and readily tunable ink viscosity, and are therefore especially suitable for printing preparation of large-scale devices. At present, the efficiency of state-of-the-art all-PSCs fabricated by the spin-coating method has exceeded 11%, laying the foundation for the preparation and practical utilization of printed devices.A high power conversion efficiency (PCE) of 11.76% is achieved based on PTzBI-Si:N2200 all-PSCs processing with 2-methyltetrahydrofuran (MTHF, an environmentally friendly solvent) and preparation of active layers by slot die printing, which is the top efficient for all-PSCs. Conversely, the PCE of devices processed by high-boiling point chlorobenzene is less than 2%. Through the study of film formation kinetics, volatile solvents can freeze the morphology in a short time, and a more rigid conformation with strong intermolecular interaction combined with the solubility limit of PTzBI-Si and N2200 in MTHF results in the formation of a fibril network in the bulk heterojunction. The multilength scaled morphology ensures fast transfer of carriers and facilitates exciton separation, which boosts carrier mobility and current density, thus improving the device performance. These results are of great significance for large-scale printing fabrication of high-efficiency all-PSCs in the future. Polymer Solar Cells

mobility. [18] However, P-OSCs have a drawback in batch-to-batch reproducibility of donor polymers, which potentially limits the mass deployment of OSCs. [19] Compared to P-OSCs, small-molecule based OSCs (SM-OSCs) are more attractive in commercialization because of well-defined molecular structures, [20][21][22] simpler synthesis and purification, [23][24][25] and low batch-to-batch variations. [26][27][28][29] With the SM donors developed, the state-of-the-art SM-OSCs show similar PCEs as those obtained for P-OSCs (over 11%) using fullerene derivative, PCBM, as the electron acceptor. [19,[30][31][32][33] However, when the NFSM acceptors were used in nonfullerene-based small molecule organic solar cells (NFSM-OSCs) their PCE can only reach slightly over 10% [34][35][36][37] which is much lower than those obtained for nonfullerene polymer solar cells (NFP-OSCs) with usually PCE over 13%. [38,39] The progress of NFSM-OSCs is strongly lagged behind their polymer counterparts.The PCE of an OSC is determined by three parameters, opencircuit voltage (V oc ), short-circuit current density (J sc ), and fill factor (FF). The main reason for the low PCE in NFSM-OSCs is due to their relative low J sc and FF. [40,41] As shown in Table S1 (Supporting Information), all of the efficient NFP-OSCs with PCE over 14% show high J sc (>20 mA cm −2 ) and high FF In this paper, two near-infrared absorbing molecules are successfully incorporated into nonfullerene-based small-molecule organic solar cells (NFSM-OSCs) to achieve a very high power conversion efficiency (PCE) of 12.08%. This is achieved by tuning the sequentially evolved crystalline morphology through combined solvent additive and solvent vapor annealing, which mainly work on ZnP-TBO and 6TIC, respectively. It not only helps improve the crystallinity of the ZnP-TBO and 6TIC blend, but also forms multilength scale morphology to enhance charge mobility and charge extraction. Moreover, it simultaneously reduces the nongeminate recombination by effective charge delocalization. The resultant device performance shows remarkably enhanced fill factor and J sc . These result in a very respectable PCE, which is the highest among all NFSM-OSCs and all small-molecule binary solar cells reported so far.

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Abstract-For this study, we compared the effectiveness of different design insoles for redistributing pressure during walking for diabetic patients and for normal control subjects. Comparisons of dynamic plantar foot pressure patterns were made with different support, including shoe-only, flat insole, and three contoured insoles. We custom-molded the three contoured insoles by casting the plantar surface of the foot under the conditions of non-weight-bearing, semi-weight-bearing, and fullweight-bearing. With the F-Scan in-shoe system, the interfacial pressure distribution during walking with different plantar supports was measured at 50 Hz for 10 s. The use of insoles could significantly reduce local peak pressure and pressure-time integral and increase the contact area. Contoured insoles were significantly better than flat insoles with regard to the insole functions in reducing local peak pressures. The insole with the semi-weight-bearing foot shape can offer the greatest peak pressure reduction compared to other insole designs, especially for patients with peak pressure located at the second to third metatarsal heads.