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Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of â¼9 ps, while that from acceptor excitations shows a rise time of â¼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.
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Many organic reactions rely on CO2 sources to generate important structural units and valuable chemicals. In this study, we compared the effects of cannabidiol (CBD) and cannabidiolic acid (CBDA) on the supercritical CO2 (scCO2)-induced de/carboxylation reaction. The results showed that CBD was directly carboxylated in the ortho-position to form CBDA with up to 62% conversion. Meanwhile, CBDA decarboxylation occurred on hemp plant material via varying composition. Mechanistic studies revealed that CBD carboxylation was influenced not only by the physical properties of scCO2, but also by the vegetable matrix.
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Canabidiol , Canabinoides , Cannabis , Dióxido de Carbono , Canabidiol/química , Cannabis/química , Canabinoides/química , Dióxido de Carbono/química , Estrutura Molecular , DescarboxilaçãoRESUMO
Giant molecular acceptors (GMAs) are typically designed through the conjugated linking of individual small molecule acceptors (SMAs). This design imparts an extended molecular size, elevating the glass transition temperature (Tg) relative to their SMA counterparts. Consequently, it effectively suppresses the thermodynamic relaxation of the acceptor component when blended with polymer donors to construct stable polymer solar cells (PSCs). Despite their merits, the optimization of their chemical structure for further enhancing of device performance remains challenge. Different from previous reports utilizing p-type linkers, here, we explore an n-type linker, specifically the benzothiadiazole unit, to dimerize the SMA units via a click-like Knoevenagel condensation, affording BT-DL. In comparison with B-DL with a benzene linkage, BT-DL exhibits significantly stronger intramolecular super-exchange coupling, a desirable property for the acceptor component. Furthermore, BT-DL demonstrates a higher film absorption coefficient, redshifted absorption, larger crystalline coherence, and higher electron mobility. These inherent advantages of BT-DL translate into a higher power conversion efficiency of 18.49 % in PSCs, a substantial improvement over the 9.17 % efficiency observed in corresponding devices with B-DL as the acceptor. Notably, the BT-DL based device exhibits exceptional stability, retaining over 90 % of its initial efficiency even after enduring 1000â hours of thermal stress at 90 °C. This work provides a cost-effective approach to the synthesis of n-type linker-dimerized GMAs, and highlight their potential advantage in enhancing intramolecular coupling for more efficient and durable photovoltaic technologies.
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Polymer solar cells (PSCs) rely on a blend of small molecular acceptors (SMAs) with polymer donors, where thermodynamic relaxation of SMAs poses critical concerns on operational stability. To tackle this issue, tethered SMAs, wherein multiple SMA-subunits are connected to the aromatic-core via flexible chains, are proposed. This design aims to an elevated glass transition temperature (Tg) for a dynamical control. However, attaining an elevated Tg value with additional SMA subunits introduces complexity to the molecular packing, posing a significant challenge in realizing both high stability and power conversion efficiency (PCE). In this study, we initiate isomer engineering on the benzene-carboxylate core and find that meta-positioned dimeric BDY-ß exhibits more favorable molecular packing compared to its para-positioned counterpart, BDY-α. With this encouraging result, we expand our approach by introducing an additional SMA unit onto the aromatic core of BDY-ß, maintaining a meta-position relative to each SMA unit location in the tethered acceptor. This systematic aromatic-core engineering results in a star-shaped C3h-positioned molecular geometry. The supramolecular interactions of SMA units in the trimer contribute to enhancements in Tg value, crystallinity, and a red-shifted absorption compared to dimers. These characteristics result in a noteworthy increase in PCE to 18.24 %, coupled with a remarkable short-circuit current density of 27.06â mA cm-2. More significantly, the trimer-based devices delivered an excellent thermal stability with over 95 % of their initial efficiency after 1200â h thermal degradation. Our findings underscore the promise and feasibility of tethered trimeric structures in achieving highly ordered aggregation behavior and increased Tg value in PSCs, simultaneously improving in device efficiency and thermal stability.
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The operational stability of polymer solar cells is a critical concern with respect to the thermodynamic relaxation of acceptor-donor-acceptor (A-D-A) or A-DA'D-A structured small-molecule acceptors (SMAs) within their blends with polymer donors. Giant molecule acceptors (GMAs) bearing SMAs as subunits offer a solution to this issue, while their classical synthesis via the Stille coupling suffers from low reaction efficiency and difficulty in obtaining mono-brominated SMA, rendering the approach impractical for their large-scale and low-cost preparation. In this study, we present a simple and cost-effective solution to this challenge through Lewis acid-catalyzed Knoevenagel condensation with boron trifluoride etherate (BF3 â OEt2 ) as catalyst. We demonstrated that the coupling of the monoaldehyde-terminated A-D-CHO unit and the methylene-based A-link-A (or its silyl enol ether counterpart) substrates can be quantitatively achieved within 30â minutes in the presence of acetic anhydride, affording a variety of GMAs connected via the flexible and conjugated linkers. The photophysical properties was fully studied, yielding a high device efficiency of over 18 %. Our findings offer a promising alternative for the modular synthesis of GMAs with high yields, easier work up, and the widespread application of such methodology will undoubtedly accelerate the progress of stable polymer solar cells.
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Imide-functionalized arenes have been one of the most promising acceptor (A) units in organic solar cells (OSCs). However, dithienophthalimide (DPI), a hybrid of thieno-[3,4-c]pyrrole-4,6-dione (TPD) and bithiophene imide (BTI) units, has not been revisited since its first synthesis, likely owing to the high synthetic cost of the reported method. In this work, we simplified the synthetic procedure of the DPI skeleton with a significant reduction of the synthetic cost by using chromium-mediated cyclization as the key chemistry. Using this method, two DPI-based nonhalogenated D-A copolymers are synthesized. The binary OSCs based on pBDTT-DPI-Me : Y6 achieves a power conversion efficiency as high as 16.55 %, highlighting DPI as an attractive A-unit for further exploration in OSCs.
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New preparation methods of vectors are the key to developing the next generation of biomacromolecule delivery systems. In this study, a controllable disulfide exchange polymerization was established to obtain low-toxicity and efficient bioreducible polyguanidines (mPEG225 -b-PSSn , n=13, 26, 39, 75, 105) by regulating the concentration of activated nucleophiles and reaction time under mild reaction conditions. The relationship between the degrees of polymerization and biocompatibility was studied to identify the optimal polyguanidine mPEG225 -b-PSS26 . Such polyguanidine exhibited good in vitro performance in delivering different functional nucleic acids. The impressive therapeutic effects of mPEG225 -b-PSS26 were further verified in the 4T1 tumor-bearing mice as well as the mice with full-thickness skin defects. Controllable disulfide exchange polymerization provides an attractive strategy for the construction of new biomacromolecule delivery systems.
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Neoplasias , Ácidos Nucleicos , Animais , Dissulfetos , Camundongos , Polimerização , Compostos de SulfidrilaRESUMO
In organic photovoltaic (OPV) blends, photogenerated excitons dissociate into charge-separated electrons and holes at donor/acceptor interfaces. The bimolecular recombination of spin-uncorrelated electrons and holes may cause nonradiative loss by forming the low-lying triplet excited states (T1) via the intermediate charge-transfer triplet states. Here, we show that such a spin-related loss channel can be suppressed in the OPV blends with fluorinated nonfullerene acceptors (NFAs). By combining ultrafast optical spectroscopy and triplet sensitization measurements, the T1 states at the acceptors have been observed to generate from the charge-separated electrons and holes in the OPV blends with a same polymer donor and two sets of NFAs with and without fluorination. The triplet formation is largely suppressed and the lifetime of charge carrier is markedly prolonged in the blends with fluorinated NFAs. The fluorination effect on the charge dynamics can be ascribed to the modified energy alignment between the triplet excited states of charge-transfer and locally excited characters as supported by quantum chemical computation. Our findings explain the mechanism responsible for the improved photocurrent generation in the OPV blends with fluorinated NFAs, suggesting that manipulating the energy landscape of triplet excited states is a promising strategy for further optimizing OPV devices.
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All-polymer solar cells (all-PSCs) have drawn tremendous research interest in recent years, due to their inherent advantages of good film formation, stable morphology, and mechanical flexibility. The most representative and most widely used n-CP acceptor was the naphthalene diimide based D-A copolymer N2200 before 2017, and the power conversion efficiency (PCE) of the all-PSCs based on N2200 reached over 8% in 2016. However, the low absorption coefficient of N2200 in the near-infrared (NIR) region limits the further increase of its PCE. In 2017, we proposed a strategy of polymerizing small-molecule acceptors (SMAs) to construct new-generation polymer acceptors. The polymerized SMAs (PSMAs) possess low band gap and strong absorption in the NIR region, which attracted great attention and drove the PCE of the all-PSCs to over 15% recently. In this Minireview we explain the design strategies of the molecular structure of PSMAs and describe recent research progress. Finally, current challenges and future prospects of the PSMAs are analyzed and discussed.
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Naphthalocyanine derivatives (SiNcTI-N and SiNcTI-Br) were firstly used as excellent cathode interlayer materials (CIMs) in organic solar cells, via introducing four electron-withdrawing imide groups and two hydrophilic alkyls. Both of them showed deep LUMO energy levels (below -3.90â eV), good thermal stability (Td >210 °C), and strong self-doping property. The SiNcTI-Br CIM displayed high conductivity (4.5×10-5 â S cm-1 ) and electron mobility (7.81×10-5 â cm2 V-1 s-1 ), which could boost the efficiencies of the PM6:Y6-based OSCs over a wide range of CIM layer thicknesses (4-25â nm), with maximum efficiency of 16.71 %.
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OBJECTIVE: To discuss the outcomes of ICSI in infertile patients with globozoospermia (GS), acephalic spermatozoa syndrome (ASS) or teratozoospermia with miniacrosome and irregular-headed sperm defect (TMRHS). METHODS: This retrospective study included 3 cases of GS, 3 cases of ASS and 2 cases of TMRHS undergoing ICSI. We analyzed the rates of fertilization, cleavage, blastocyst formation, implantation, clinical pregnancy and live birth in the three groups of patients. RESULTS: The patients of the GS and ASS groups all achieved clinical pregnancies and healthy births, but those of the TMRHS group showed a lower fertilization rate than the other two groups and achieved no clinical pregnancy. CONCLUSIONS: ICSI could achieve successful clinical pregnancy in infertile patients with globozoospermia or acephalic spermatozoa syndrome, but no satisfactory clinical outcome in those with miniacrosome and irregular-headed sperm defect, though it has to be further proved by more studies with larger-sized samples.
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Injeções de Esperma Intracitoplásmicas , Teratozoospermia/terapia , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Espermatozoides/patologia , Resultado do TratamentoRESUMO
Prostate cancer (PCa) is one of the major cancers affecting males with high mortality around the world. Recent studies have found that some long noncoding RNAs play a critical part in the cellular processes of PCa. In our study, aberrant expressed lymphoid enhancer-binding factor-1 antisense RNA 1 (LEF1-AS1), microRNA-330-5p (miR-330-5p), and lymphoid enhancer-binding factor-1 (LEF1) were screened out from a microarray database, the role of the novel noncoding RNA regulatory circuitry in the initiation and development of PCa was investigated. LEF1-AS1 and LEF1 were highly expressed while miR-330-5p was poorly expressed in PCa. Following that, the PCa PC-3 cell line was adopted for subsequently experiments, in which the expression of LEF1-AS1 and miR-330-5p was subsequently altered by means of exogenous transfection. After that, the effects of up- or downregulation of LEF1-AS1 and miR-330-5p on epithelial-mesenchymal transition (EMT) and the cell ability for proliferation, invasion, migration in vitro, and tumorigenesis and lymph node metastasis (LNM) in vivo were evaluated. RNA crosstalk revealed that LEF1-AS1 bound to miR-330-5p and LEF1 was the target gene of miR-330-5p. Silenced LEF1-AS1 or elevated miR-330-5p exhibited inhibited EMT processes, reduced ability of proliferation, invasion and migration, coupling with decreased tumorigenesis and LNM in nude mice. The key findings of this study collectively propose downregulation of LEF1-AS1 competing with miR-330-5p to inhibit EMT, invasion and migration of PCa by LEF1 repression.
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Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/prevenção & controle , Interferência de RNA , RNA Longo não Codificante , Idoso , Idoso de 80 Anos ou mais , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Neoplasias ExperimentaisRESUMO
BACKGROUND/AIMS: Obstructive sleep apnea is associated with diabetes and insulin resistance, but the underlying mechanisms remain unclear. The purpose of the current study was to determine the molecular effects of intermittent hypoxia (IH) on hepatic insulin signaling and glucose homeostasis, and whether c-Jun NH2-terminal-kinase (JNK) contributed to metabolic responses to IH in liver cells. METHODS: The human HepG2 cells and rat FAO cells were exposed to 10, 30, 120, 240 or 360 cycles of IH (1% O2 for 60 s followed by 21% O2 for 60s, 7.5 cycles per hour) or normoxia as a control. In a subgroup, we exposed cells to 360 cycles of IH with the JNK inhibitor SP600125. After IH exposure, cell glycogen content and glucose output were measured using colorimetric assay kits. Canonical insulin signaling and gluconeogenic genes were measured by western blot and quantitative polymerase chain reaction. RESULTS: IH decreased insulin-stimulated protein kinase B (AKT)/glycogen synthase kinase-3ß (GSK-3ß) phosphorylation in a time-dependent manner, while inhibiting forkhead box protein O1 (FOXO1) expression and phosphoenolpyruvate carboxykinase (PEPCK) transcription independent of insulin signaling. JNK inhibitor SP600125 partially restored AKT/ GSK-3ß phosphorylation and glycogen synthesis, but did not affect other IH-induced glucose metabolic changes. CONCLUSION: IH in vitro impaired insulin signal transduction in liver cells as assessed by inhibited AKT/GSK-3ß phosphorylation via JNK activation. IH inhibited FOXO1 and gluconeogenesis in an insulin-independent manner.
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Glucose/metabolismo , Homeostase , Insulina/metabolismo , Fígado/metabolismo , Transdução de Sinais , Hipóxia Celular , Proteína Forkhead Box O1/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Hep G2 , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the world. Although considerable progress has been made in the diagnosis, treatment and prognosis of CVD, there is still a critical need for novel diagnostic biomarkers and new therapeutic interventions to decrease the incidence of this disease. Recently, there is increasing evidence that circulating miRNAs (miRNAs), i.e. endogenous, stable, single-stranded, short, non-coding RNAs, can be used as diagnostic biomarkers for CVD. Furthermore, miRNAs represent potential novel therapeutic targets for several cardiovascular disorders. In this review we provides an overview of the effects of several CVD; including heart failure, acute myocardial infarction, arrhythmias and pulmonary hypertension; on levels of circulating miRNAs. In addition, the use of miRNA as therapeutic targets is also discussed, as well as challenges and recommendations in their use in the diagnosis of CVD.
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Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , MicroRNAs/análise , Biomarcadores/análise , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
OBJECTIVE: To identify potential serum biomarkers for distinguishing between latent tuberculosis infection (LTBI) and active tuberculosis (TB). METHODS: A proteome microarray containing 4,262 antigens was used for screening serum biomarkers of 40 serum samples from patients with LTBI and active TB at the systems level. The interaction network and functional classification of differentially expressed antigens were analyzed using STRING 10.0 and the TB database, respectively. Enzyme-linked immunosorbent assays (ELISA) were used to validate candidate antigens further using 279 samples. The diagnostic performances of candidate antigens were evaluated by receiver operating characteristic curve (ROC) analysis. Both antigen combination and logistic regression analysis were used to improve diagnostic ability. RESULTS: Microarray results showed that levels of 152 Mycobacterium tuberculosis (Mtb)-antigen- specific IgG were significantly higher in active TB patients than in LTBI patients (P < 0.05), and these differentially expressed antigens showed stronger associations with each other and were involved in various biological processes. Eleven candidate antigens were further validated using ELISA and showed consistent results in microarray analysis. ROC analysis showed that antigens Rv2031c, Rv1408, and Rv2421c had higher areas under the curve (AUCs) of 0.8520, 0.8152, and 0.7970, respectively. In addition, both antigen combination and logistic regression analysis improved the diagnostic ability. CONCLUSION: Several antigens have the potential to serve as serum biomarkers for discrimination between LTBI and active TB.
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Tuberculose Latente/diagnóstico , Análise Serial de Proteínas/métodos , Proteômica/métodos , Adolescente , Adulto , Idoso , Anticorpos Antibacterianos , Especificidade de Anticorpos , Antígenos de Bactérias , Biomarcadores/sangue , Feminino , Humanos , Tuberculose Latente/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Proteoma/genética , Curva ROC , Adulto JovemRESUMO
OBJECTIVE: To gain a deeper insight into the local anatomic structures of the seminal vesicle and ejaculatory duct and provide some anatomic guidance in seminal vesiculoscopy. METHODS: We analyzed the clinical data on 48 cases of seminal vesiculoscopy and recorded the surgical approaches to the seminal vesicle and clinical effects after operation. At the same time, we made an anatomic study of the seminal vesicle, ejaculatory duct and prostatic utricle and simulated the surgical approaches in 12 adult pelvis specimens. RESULTS: The anatomical results accorded well with the surgical findings. The ejaculatory ducts failed to be revealed for 52.1%ï¼25/48ï¼, but 93.8%(45/48) of the operations were completed through different approaches into the seminal vesicle. CONCLUSIONS: Transurethral seminal vesiculoscopy can be applied in the treatment of seminal tract and seminal vesicle diseases, but has its obvious limitations and has to be used with other strategies to achieve better results.
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At present, the disjointing situation is generally present between "systemic"and "local", "macro" and "micro", "in vivo process" and "activity evaluation" in the study of traditional Chinese medicine (TCM). An urgent task for the modernization of TCM is to establish new strategies and methods which can reflect the overall characteristics of TCM. The introduction of integrative pharmacology provided a feasible approach to solve the problem of the fragmentation of TCM. Internet-based computation platform method was adopted in this study to explore the active molecular mechanism of Mylabris in the treatment of colorectal cancer. Based on the analysis of the functional integration of internet-based computation platform V1.0 version software, the "core components-key target- main pathway" multidimensional network of Mylabris in treatment of colorectal cancer disease was constructed to explore the potential molecular mechanism of Mylabris in treatment of colorectal cancer from multiple perspectives. The results showed that Mylabris can treat the colorectal cancer and the mechanism might be associated with amino acid metabolism, NF-κB signaling pathway, immune system, endocrine system, nervous system, and chemokine signal transduction pathway, epithelial cell signaling in helicobacter pylori infection, T cell receptor signaling pathway, B cell receptor signaling pathway and so on.
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Besouros , Neoplasias Colorretais/tratamento farmacológico , Materia Medica/uso terapêutico , Transdução de Sinais , Animais , Humanos , Medicina Tradicional Chinesa , SoftwareRESUMO
Chinese medicine prescription is the main form and means to treat diseases in traditional Chinese medicine (TCM). However, the disjointing situation is generally present between "systemic" and "local", "macro" and "micro", "in vivo process" and "activity evaluation" in the study of TCM at present. An urgent task for the modernization of TCM is to establish new strategies and methods which can reflect the overall characteristics of TCM. The introduction of integrative pharmacology provided a feasible approach to solve the problem of the fragmentation of TCM. Internet-based computation platform method was adopted in this study to explore the active molecular mechanism of Yinchenhao decoction in the treatment of cirrhosis. Based on the analysis of the functional integration of Internet-based Computation Platform V1.0 version software, the "core components-key target- main pathway" multidimensional network of Yinchenhao decoction in treatment of cirrhosis disease was constructed to explore the potential molecular mechanism of Yinchenhao decoction in treatment of cirrhosis from multiple perspectives. The molecular mechanism analysis of Yinchenhao decoction showed that Yinchenhao decoction can achieve the therapeutic effect on cirrhosis and the mechanism might be associated with oxidative phosphorylation, energy metabolism, circulatory system, glycerophospholipid metabolis, lipid metabolism and other pathways. Yinchenhao decoction in treatment of cirrhosis may be associated with energy metabolism and lipid metabolism.
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Medicamentos de Ervas Chinesas/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Medicina Tradicional Chinesa , Metabolismo Energético , Humanos , Metabolismo dos LipídeosRESUMO
All-polymer solar cells (all-PSCs) can offer unique advantages for applications in flexible devices, and naphthalene diimide (NDI)-based polymer acceptors are the widely used polymer acceptors. However, their power conversion efficiency (PCE) still lags behind that of state-of-the-art polymer solar cells, due to low light absorption, suboptimal energy levels and the strong aggregation of the NDI-based polymer acceptor. Herein, a rhodanine-based dye molecule was introduced into the NDI-based polymer acceptor by simple random copolymerization and showed an improved light absorption coefficient, an up-shifted lowest unoccupied molecular orbital level and reduced crystallization. Consequently, additive-free all-PSCs demonstrated a high PCE of 8.13 %, which is one of the highest performance characteristics reported for all-PSCs to date. These results indicate that incorporating a dye into the n-type polymer gives insight into the precise design of high-performance polymer acceptors for all-PSCs.
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Considering the potential applications of all-polymer solar cells (all-PSCs) as wearable power generators, there is an urgent need to develop photoactive layers that possess intrinsic mechanical endurance, while maintaining a high power-conversion efficiency (PCE).Herein a strategy is demonstrated to simultaneously control the intercalation behavior and nanocrystallite size in the polymer-polymer blend by using a newly developed, high-viscosity polymeric additive, poly(dimethylsiloxane-co-methyl phenethylsiloxane) (PDPS), into the TQ-F:N2200 all-PSC matrix. A mechanically robust 10wt% PDPS blend film with a great toughness was obtained. Our results provide a feasible route for producing high-performance ductile all-PSCs, which can potentially be used to realize stretchable all-PSCs as a linchpin of next-generation electronics.