Since the first demonstration, the electrolyte-gated organic field-effect transistors (EGOFETs) have immediately gained much attention for the development of cutting-edge technology and they are expected to have a strong impact in the field of (bio-)sensors. However EGOFETs directly expose their active material towards the aqueous media, hence a limited library of organic semiconductors is actually suitable. By using two mostly unexplored strategies in EGOFETs such as blended materials together with a printing technique, we have successfully widened this library. Our benchmarks were 6,13-bis(triisopropylsilylethynyl)pentacene and 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES-ADT), which have been firstly blended with polystyrene and secondly deposited by means of the bar-assisted meniscus shearing (BAMS) technique. Our approach yielded thin films (i.e. no thicker than 30 nm) suitable for organic electronics and stable in liquid environment. Up to date, these EGOFETs show unprecedented performances. Furthermore, an extremely harsh environment, like NaCl 1M, has been used in order to test the limit of operability of these electronic devices. Albeit an electrical worsening is observed, our devices can operate under different electrical stresses within the time frame of hours up to a week. In conclusion, our approach turns out to be a powerful tool for the EGOFET manufacturing.

Herein graphene quantum dot (GQD), a graphene material with lateral dimension less than 100 nm, is explored to dope PPy on F-doped tin oxide glass as an efficient counter electrode for high-performance dye-sensitized solar cells (DSSCs). The GQDs-doped PPy film has a porous structure in comparison to the densely structured plain PPy, and displays higher catalytic current density and lower charge transfer resistance than the latter toward I3(-)/I(-) redox reaction. The highest power conversion efficiency (5.27%) for DSSCs is achieved with PPy doped with10% GQDs, which is comparable to that of Pt counter electrode-based DSSCs. This work provides an inexpensive alternative to replace platinum for DSSCs.

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This communication presents a novel electrolyte gated field-effect transistor based on a blend of dibenzo-tetrathiafulvalene and polystyrene deposited through bar-assisted meniscus shearing. This technique allows the fabrication of high performing electronic devices suitable for (bio)sensing applications and might capture industrial interest due to its scalability. The reported devices can operate in aqueous solution with comparable complexity to real samples.

Dark septate endophytes (DSE) protect host plants against a variety of environmental stresses, however our knowledge about the roles of DSE in improving drought tolerance of crops is poor. In this study, sorghum (Sorghum bicolor L. Moench) was inoculated with a DSE strain (Exophiala pisciphila GM25) under two different soil water conditions (well-watered (WW), -0.11 MPa; drought-stressed (DS), -0.69 MPa) for one month. At the end of this experiment, sorghum roots were obviously colonized by DSE with 50.5%-62.5% colonization rate. When compared with non-inoculated seedlings under both WW and DS conditions, E. pisciphila-inoculated sorghum had greater plant height, collar diameter, shoot dry weight, net photosynthetic rate (Pn), stomatal conductance (g s ), transpiration rate (E), maximal photochemical efficiency of PSII photochemistry (Fv/Fm) and actual quantum yield (PSII), and lower intercellular CO 2 concentration (Ci). In addition, in comparison to noninoculation under DS conditions, E. pisciphila inoculation also improved the root dry weight, non-photochemical quenching values (NPQ), photochemical quenching values (qP), increased the content of related secondary metabolites including anthocyanin, polyphenol and flavonoid and enhanced the enzymatic activities related to secondary metabolism, such as cinnamyl alcohol dehydrogenase (CAD), phenylalanine ammonia-lyase (PAL), guaiacol peroxidase (G-POD) in sorghum seedlings. Our results demonstrated that the drought resistance of sorghum seedlings were positively improved by E. pisciphila inoculation with better plant growth, gas exchange, photosynthesis, chlorophyll fluorescence, secondary metabolites and enzyme activities related to secondary metabolism. Inoculation with E. pisciphila is an efficient strategy to survive for sorghum in drought environment.

wileyonlinelibrary.com COMMUNICATIONis the PP lifetime and τ SL is the spin-lattice relaxation time. [ 20 ] In general, F substantially reduce the MEL value if τ / τ SL > 1. This may be the reason that MEL| max has been limited so far to ≈10%-20% in conventional (exciton-based) OLEDs. [ 21 ] One method for enhancing MEL| max in OLEDs is increasing τ SL , so that even weak spin-mixing interactions may still be effective in changing ρ with B . [ 20 ] Another way to increase MEL| max is by involving other spin-mixing channels that may not have an obvious upper bound for changing ρ . One such spin-mixing process is the so called reverse intersystem crossing (RISC) which is recently proposed by Adachi et al. in exciplex-based OLEDs. [ 22,23 ] Usually the RISC in exciplexOLEDs is thermally activated. [22][23][24] In the thermally activated RISC process, a large number of triplet exciplexes can convert into singlets assisted with thermal energy due to the small energy different (<50 meV) between the singlet and triplet exciplexes. [ 23,24 ] In this case, RISC process would provide an alternative spin-mixing channel to manipulate the ρ of singlet/triplet exciplexes, which is expected to induce large magnetic fi eld responses. Based on this concept, Basel et al. have reported large magneto-photoluminescence (≈5%) and MEL (≈35%) in electron donor-acceptor (D-A) blend exciplex-based OLEDs. [ 19 ] However, it should be emphasized that these values are still far away from the requirement for any sensor and/or display applications. In the meanwhile, Ling et al. have reported a much larger MEL (up to ≈110%) in another D-A combination exciplex-based OLEDs. [ 25 ] Unfortunately, the origin of such large MEL is quite obscure. Worsely, from the fundamental mechanism perspective, the critical factors that determine the magnitude of MEL| max in such D-A exciplex-based OLEDs are still missing. Therefore, it is desirable to get a more general understanding of MEL in such exciplex-based OLEDs and fi nd the way to achieve really high magnetic fi eld responses for some useful applications.In this communication, systematic studies on MEL in exciplex-OLEDs based on a series of D-A composites were reported as well as ultralarge MEL (up to ≈160%) and MC (as high as ≈115%) at room temperature. As will be demonstrated in detail in the following text that the crucial parameter that determines the MEL| max is activation energy ( E a ), which in turn is determined by the energy different between the singlet and triplet exciplexes (Δ E 1,3 DOI: 10.1002/adom.201600015The spin degree of freedom plays an important role in photophysical processes of organic light-emitting diodes (OLEDs) based on π-conjugated polymers and small molecules. [1][2][3] Therefore, application of an external magnetic fi eld, B , enables manipulation of the device current, dubbed magneto-conductivity (MC), as well as its electroluminescence (EL) emission intensity and dubbed magneto-electroluminescence (MEL). [4][5][6][7][8][9] When considering the MEL mechanism we note tha...

In this work, we report on large magneto-conductance (MC) over 60% and magneto-electroluminescence (MEL) as high as 112% at room temperature in an exciplex-based organic light-emitting diode (OLED) with efficient reverse intersystem crossing (ISC). The large MC and MEL are individually confirmed by the current density-voltage characteristics and the electroluminescence spectra under various magnetic fields. We proposed that this type of magnetic field effect (MFE) is governed by the field-modulated reverse ISC between the singlet and triplet exciplex. The temperature-dependent MFEs reveal that the small activation energy of reverse ISC accounts for the large MFEs in the present exciplex-based OLEDs.

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