The influence of solvent on the electrochemical property and conductivity of PEDOT has been investigated by electrochemical and physical characterizations. The PEDOT treated with different solvents reveals a different reversibility of ionic transport and cycling stability, which is associated with the conformational rearrangement from aggregated to linear polymer chains, as evidenced from atomic force microscopy (AFM). The conductivity of the PEDOT thin film can also be enhanced while the degree of linear polymer chains is higher. The application of highly conductive PEDOT thin film as a buffer layer in the polymer photovoltaic devices was realized. A PCE of 4.27% for photovoltaic devices based on P3HT-PCBM under simulated sun light is achieved by using a PEDOT thin film treated with DMSO.

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We report a comprehensive study on influence of oxygen partial pressure on NiO thin films grown on glass substrates in a combined argon and oxygen ambience by reactive dc magnetron sputtering. In this present article, we have discussed the dependence of oxygen pressure on structural, chemical, morphological, optical and electrical properties of the sputtered NiO films. Glancing angle x-ray diffraction reveals that the deposited films were polycrystalline in nature with FCC phase. The preferred orientation changes from (200) to (111) in a higher O 2 flow rate environment and an average particle size was estimated using Scherrer relation. The surface morphology of films was studied by using atomic force microscopy. The x-ray photoelectron spectroscopy analysis demonstrates the core level Ni 2p spectra over a range of 850 eV to 885 eV of binding energy and observed Ni 2p 3/2 , Ni 2p 1/2 domains along with their satellite peaks. It infers the presence of both Ni +2 and Ni +3 oxidation states in the sputtered films. Additionally, Raman spectroscopy was carried out to confirm the structural defects level and crystalline nature of the films. The optical results show that deposited films were semi-transparent and the evaluated optical band gap of the material lies in the range 3.36 eV to 3.52 eV. The extracted electrical properties infer either n-type or p-type conductivity depending on the processing conditions of the films.

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C60‐based thin‐film transistors are fabricated through solution processing. On rigid indium tin oxide glass, the transistors display electron mobilities as high as 0.21 cm2 V−1 s−1 and a threshold voltage of 0.7 V, only slightly lower than those of organic thin‐film transistors prepared through vacuum deposition. On ITO‐coated PET substrates, the mobilities in the flexible devices (see image) are approximately one order of magnitude lower than those of devices prepared on rigid glass substrates.