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Stretchable conducting films are a prime necessity for future stretchable and wearable electronics. In this work, highly conducting poly(3,4 ethylenedioxythiophene):Tosylate (PEDOT:Tos) films are deposited on extremely stretchable styrene‐ethylene‐butylene‐styrene (SEBS) substrates via vapor phase polymerization (VPP) and their inherent properties are systematically studied. The charge transport and electrical properties of VPP PEDOT:Tos stretchable films are measured from room temperature down to the low temperature of 5 K. Interestingly, the mechanical properties of the stretchable substrate lead to buckling of the PEDOT:Tos that affect the electrical conductivity but not the charge carrier mobility, optical, and structural properties. The VPP PEDOT:Tos on the stretchable SEBS substrate show a semiconducting behavior as electrical resistance is enhanced upon cooling from room temperature to 5 K. Such kind of stretchable conducting films can be used for stretchable transistors, wearable sensing, energy storage, and electrochromic applications. [ABSTRACT FROM AUTHOR]

It is well established that plants need a range of soil nutrients to grow. In farming, these nutrients are generally added to the soil in the form of fertilizers. However, depending on the soil conditions (such as temperature, water content, pH, and soil type), nutrients may not be in the right form for plant uptake. Determining the availability of nutrients in the soil for plant growth is therefore critical for the yield and productivity of modern farming. A considerable amount of research and knowledge has been developed that shows the importance of the soil pH on the availability (or not) of nutrients. Furthermore, pH plays a crucial role in controlling the availability of potential toxic elements, such as aluminum and manganese. This review article discusses recent research aimed at real‐time and continuous soil pH measurement in‐situ. More specifically, it focuses on the development of polymer materials that will ultimately enable pH measurements for the specific application of in‐ground pH sensing. Given the breadth of the polymeric sensor research field, this review has a narrowed focus on optical and electrochemical transduction methods. [ABSTRACT FROM AUTHOR]

Conducting polymers such as poly-(3,4-ethylenedioxythiophene) (PEDOT) are widely researched for application in electronic devices. Researcher's look to exploit the ability of these polymers to conduct electrical charge. To induce conductivity, the polymers are doped with counterions; for PEDOT, this is typically done with poly-(styrenesulfonate) or tosylate (Tos). The Tos anions inserted within the PEDOT nanostructure stabilize positive defects (holes) on the polymer's conjugated backbone, which, in turn, facilitates electrical conduction. In this study, we use X-ray photoelectron spectroscopy to investigate the Tos doping of PEDOT within the outermost region (<15 nm) of electrochemically oxidized or reduced PEDOT:Tos nanoscale films. Computation of the predicted density of states from density functional theory studies is also conducted to aid in interpreting the ultraviolet photoelectron spectroscopy spectra. We observe that the doping of PEDOT:Tos is more complex than first thought, likely involving the nonionic triblock copolymer used during PEDOT's oxidative polymerization. This hypothesis is corroborated by time-of-flight secondary-ion mass spectrometry measurements on the outer 2 nm of the oxidized and reduced PEDOT:Tos. The observation of complex and heightened doping near the surface opens opportunities for the deliberate surface engineering of PEDOT:Tos nanofilms in polymer electronic applications such as electrochemical transistors and electrical connections. [ABSTRACT FROM AUTHOR]

Metallic thin films have been evaluated as adhesive layers for first surface mirrors. Thin films (0.5–4 nm thick) of Cr, Cu, Ge, Sn, and Ni, capped with an over layer of 100 nm of Ag have been deposited by means of ion assisted electron beam evaporation onto glass substrates. The specular reflectance, conductivity, morphology, adhesion, and abrasion resistance of the mirrors have been assessed and compared. This work demonstrates the superior Ni and Ge adhesion and abrasion resistance to Ag thin films, while Cr and again Ni are the best candidates in terms of reflectance enhancement. In particular, 4 nm of Ni increases the Ag reflectance from 95.7% to 96.7%, exhibits the strongest adhesion as determined by the cross hatch tape test and the lowest loss of material after the different abrasion tests is just 50% in comparison to 100% for Ag‐coated glass substrates. [ABSTRACT FROM AUTHOR]

ABSTRACT A study using three different pairs of electrochromic polymers (ECPs) synthesized onto plaques by means of a modified vapor phase polymerization (VPP) technique is presented. Restriction of the respective polymerization times, allowed both faster and slower polymerizing monomers to be controlled, and produced blended plaques with visually diffuse interfaces. The ECPs within the blended plaques retain their individual electrochromic behavior and when encapsulated into an electrochromic device, show outstanding optical switching performance with little degradation evident over 10,000 cycles, coupled with a switching time of the order of 1 second. Blends also allow multiple diffuse color changes within an electrochromic device, due to the difference in oxidation potentials of the individual ECPs, making them candidates for adaptive camouflage use. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42158. [ABSTRACT FROM AUTHOR]

Highlights • PEDOT doped with tosylate was fabricated using vapour phase polymerisation. • Electrochemical reduction was used to remove most, but not all tosylate from the PEDOT. • Reduced PEDOT was exposed to different concentrations of NO 3 in solution. • PEDOT-tosylate of different structure and morphology interacted differently with NO 3. Abstract The ability to sense and monitor aspects of a process or environment is becoming of utmost importance as digital technology integrates into our daily lives. This is true for agriculture where knowledge of real time levels of fertiliser in soil is empowering farmers. Such sensing and monitoring requires understanding of the structure-property-performance relationships of specific materials. In this study this relationship for the conducting polymer poly(3,4-ethylenedioxythiophene), PEDOT, and its passive doping with nitrate (NO 3) is explored. The highly ordered structure of vapour deposited PEDOT doped with tosylate (Tos) is commensurate with high doping levels. In turn this correlates with the nitrate doping level in PEDOT-Tos/NO 3 being sensitive to NO 3 concentration in the surrounding solution. Such an understanding has impact for potentially designing other conducting polymers for ion sensing applications. [ABSTRACT FROM AUTHOR]