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Three small molecules named DR3TBDTT, DR3TBDTT-HD, and DR3TBD2T with a benzo[1,2-b:4,5-b']dithiophene (BDT) unit as the central building block have been designed and synthesized for solution-processed bulk-heterojunction solar cells. Power conversion efficiencies (PCEs) of 8.12% (certified 7.61%) and 8.02% under AM 1.5G irradiation (100 mW cm(-2)) have been achieved for DR3TBDTT- and DR3TBDT2T-based organic photovoltaic devices (OPVs) with PC71BM as the acceptor, respectively. The better PCEs were achieved by improving the short-circuit current density without sacrificing the high open-circuit voltage and fill factor through the strategy of incorporating the advantages of both conventional small molecules and polymers for OPVs.

A series of acceptor-donor-acceptor simple oligomer-like small molecules based on oligothiophenes, namely, DRCN4T-DRCN9T, were designed and synthesized. Their optical, electrical, and thermal properties and photovoltaic performances were systematically investigated. Except for DRCN4T, excellent performances were obtained for DRCN5T-DRCN9T. The devices based on DRCN5T, DRCN7T, and DRCN9T with axisymmetric chemical structures exhibit much higher short-circuit current densities than those based on DRCN6T and DRCN8T with centrosymmetric chemical structures, which is attributed to their well-developed fibrillar network with a feature size less than 20 nm. The devices based on DRCN5T/PC71BM showed a notable certified power conversion efficiency (PCE) of 10.10% under AM 1.5G irradiation (100 mW cm(-2)) using a simple solution spin-coating fabrication process. This is the highest PCE for single-junction small-molecule-based organic photovoltaics (OPVs) reported to date. DRCN5T is a rather simpler molecule compared with all of the other high-performance molecules in OPVs to date, and this might highlight its advantage in the future possible commercialization of OPVs. These results demonstrate that a fine and balanced modification/design of chemical structure can make significant performance differences and that the performance of solution-processed small-molecule-based solar cells can be comparable to or even surpass that of their polymer counterparts.

Displays are basic building blocks of modern electronics 1,2. Integrating displays into textiles 17 offers exciting opportunities for smart electronic textiles-the ultimate form of wearables 18 poised to change the way we interact with electronic devices 3-6. Display textiles serve to bridge human-machine interactions 7-9 , offering for instance, a real-time communication tool for individuals with voice or speech disorders. Electronic textiles capable of communicating 10 , sensing 11,12 and supplying electricity 13,14 have been reported previously. However, textiles 22 with functional, large-area displays have not been achieved so far because obtaining small illuminating units that are both durable and easy to assemble over a wide area is challenging. Here, we report a 6 m (L) × 25 cm (W) display textile containing 5×10 5 electroluminescent (EL) units narrowly spaced to ~800 μm. Weaving conductive weft and luminescent warp fibres forms micron-scale EL units at the weft-warp contact points. Brightness between EL units deviates by < 6.3% and remains stable even when the textile is bent, stretched or pressed. We attribute this uniform and stable lighting to the smooth luminescent coating around the 2 warp fibres and homogenous electric field distribution at the contact points. Our display textile is flexible and breathable and withstands repeatable machine-washing, making them suitable for practical applications. We show an integrated textile system consisting of display, 32 keyboard and power supply can serve as a communication tool, which could potentially drive 33 the Internet of Things in various areas including healthcare. Our approach unifies the 34 fabrication and function of electronic devices with textiles, and we expect weaving fibre 35 materials to shape the next-generation electronics.

Small molecules, namely, DCAO(3)TBDT and DR(3)TBDT, with 2-ethylhexoxy substituted BDT as the central building block and octyl cyanoacetate and 3-ethylrhodanine as different terminal units with the same linkage of dioctyltertthiophene, have been designed and synthesized. The photovoltaic properties of these two molecules as donors and fullerene derivatives as the acceptors in bulk heterojunction solar cells are studied. Among them, DR(3)TBDT shows excellent photovoltaic performance, and power conversion efficiency as high as 7.38% (certified 7.10%) under AM 1.5G irradiation (100 mW cm(-2)) has been achieved using the simple solution spin-coating fabrication process, which is the highest efficiency reported to date for any small-molecule-based solar cells. The results demonstrate that structure fine turning could cause significant performance difference and with that the performance of solution-processed small-molecule solar cells can indeed be comparable with or even surpass their polymer counterparts.

In the past few years, great progress has been made in organic photovoltaic (OPV) cells for an alternate of silicon semiconductorbased solar cells. OPV has the advantages of clean, low-cost, flexibility, and the possibility of roll-to-roll production. [1][2][3][4] Currently, most of the works have been focused on polymer donor molecules using bulk heterojunction (BHJ) architecture and [6,6]-phenyl-C61-butyric acid methyl ester (PC 61 BM) as the acceptor. [5,6] Indeed, in addition to the currently better OPV performance than small molecules, polymers have the advantages for such as better film forming quality and so on. [7] However, it cannot be denied that there are disadvantages for polymer-based OPV, such as batch to batch reproducibility, difficulty of purification, and so on. In contrast, small molecules intrinsically do not have such flaws; [8] additionally, their band structures could be tuned easily with much more choices of chemical modification. Furthermore, small molecules generally have higher charge mobility and open voltages. [9,10] However, even with these advantages, small-molecule-based OPV cells have not been investigated as intensively as that of their polymer counterparts because one of the major problems for small molecules is their generally poor film quality when using the simple solution spinning process. [11] This has been hampering their performance, and indeed their power conversion efficiencies (PCEs) (4%-5%) [12][13][14][15][16][17][18] are still significantly lower compared with that (>7%) [19][20][21][22][23][24][25] from polymers. It is thus expected that better PCE could be achieved when their intrinsic bad film quality and morphology in BHJ architecture could be improved combining with their other advantages. But to achieve this, careful molecule design has to be carried out to address many factors collectively, including their molar absorption, morphology compatibility with the acceptors for a better film quality, and so on.Previously, we have reported a small molecule (DCAO7T, Scheme 1), which gives rather high quality of solution spincoated film and a high 5.08% PCE. [12] But this molecule comes with an end unit of cyanoacetate group, which could not contribute too much for the overall solar absorption. So, we thought that the current density J sc might be able to be enhanced if structures with stronger molar absorption is used to replace such an end unit, in the conditions that overall molecular backbone and morphology will not be affected too much. Considering the generally high absorption coefficients and good OPV performance of many dye molecules, such as triarylamines, [16,26] acenaphthoquinoxaline, [27] diketopyrrolopyrroles (DPP), [17] squaraines, [18,28,29] merocyanine, [30,31] isoindigo, [32] pthalocyanine, [33] and dipyrromethene boron difluoride (BODIPY), [34][35][36] we thus introduce a new dye unit, 3-ethylrhodanine, into the targeted OPV molecule named as DERHD7T (Scheme 1) with a conjugated thiophene backbone. With such a design, DERHD7T is expected to have a str...

There are currently two distinct models proposed to explain why both MDM2 and MDMX are required in p53 control, with a key difference centered on whether these two p53 inhibitors work together or independently. To test these two competing models, we generated knockin mice expressing a point mutation MDMX mutant (C462A) that is defective in MDM2 binding. This approach allowed a targeted disassociation of the MDM2/MDMX heterocomplex without affecting the ability of MDMX to bind to p53, and while leaving the MDM2 protein itself completely untouched. Significantly, Mdmx C462A/C462A homozygous mice died at approximately day 9.5 of embryonic development, as the result of a combination of apoptosis and decreased cell proliferation, as shown by TUNEL and BrdU incorporation assays, respectively. Interestingly, even though the MDMX mutant protein abundance was found slightly elevated in the Mdmx C462A/C462A homozygous embryos, both the abundance and activity of p53 were markedly increased. A p53-dependent death was demonstrated by the finding that concomitant deletion of p53 completely rescued the embryonic lethality in Mdmx C462A/C462A homozygous mice. Our data demonstrate that MDM2 and MDMX function as an integral complex in p53 control, providing insights into the nonredundant nature of the function of MDM2 and MDMX.knockin mouse model | p53 regulation U nder normal physiological conditions, wild-type p53 protein levels must be kept low owing to its growth-inhibitory activities, and this control is mainly modulated via regulation of p53 protein stability. Although a number of different regulators have been reported to be involved in this protein regulation, MDM2 has been shown to be the principal player in control of p53 turnover (1). MDM2 primarily functions as an E3 ubiquitin ligase targeting p53 for ubiquitination and subsequent degradation. At the same time, p53 induces the expression of the Mdm2 gene, forming a negative feedback loop (1). The importance of MDM2 in p53 control is highlighted by the finding that Mdm2 knockout results in p53-dependent embryonic lethality in mice (2, 3).MDMX (also known as MDM4), which was originally isolated as a novel p53-interacting protein, shares substantial structural homology with MDM2 (4, 5). The highest sequence similarity between MDM2 and MDMX lies at the N terminus and contains a p53-binding domain, and the two also share high sequence homology in a RING-finger domain, a region that mediates the association between MDMX and MDM2 (6,7). Genetic studies have demonstrated that like MDM2, MDMX is another essential negative regulator of p53 (8-10). Although it remains unclear why both MDM2 and MDMX are required for p53 control, a model has been proposed that these two proteins function independently. On the basis of the fact that unlike MDM2, MDMX lacks an intrinsic ubiquitin E3 ligase activity, it has been proposed that MDMX inhibits p53 chiefly by binding to the p53 transactivation domain and antagonizing p53 transcription activity, whereas MDM2 inactivates p53 primarily by wo...

An electron-withdrawing terminal small molecule with dithienosilole core shows high photovoltaic performance. The DCAO3TSi:PC61BM based solar cell exhibits a power conversion efficiency of 5.84%, with an open circuit voltage (V oc) of 0.80 V, a short-circuit current density (J sc) of 11.51 mA·cm−2, and a high fill factor (FF) of 0.64the best so far for a solution-processed small molecule based solar cell.