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The discovery of conducting polymers 40 years ago paved the way for organic electronics promising exciting new applications. Already a considerable range of electronic devices containing (semi) conducting polymers has been developed like light emitting diodes, non-linear optical devices, artificial muscles, thin film transistors and large area photovoltaic devices. Incorporating organic compounds extracted from plants (so called 'green' materials) in these devices may improve stability, sustainability and manufacturing costs. Green materials are processed under ambient atmosphere using simple deposition techniques like spin and dip coating or drop casting. Even well known organic semiconductors behave differently under these conditions. As a model system and reference for green materials, we reinvestigated the injection of holes into the regioregular semiconducting polymer poly(3-hexylthiophene-2,5-diyl) (P3HT). P3HT is known to be sensitive to ambient dopants, like moisture, oxygen or reminiscent solvents. In the present work, special emphasis is given to understanding the electrical signature of degrading processes, which affect both the bulk and the interfaces of the organic semiconductor. To this extend the charge injection into P3HT was monitored after various drying scenarios, heat treatment (annealing) and aging. Especially fruitful proved the comparison of charge injection across a metal-semiconductor interface and an organic heterojunction in the same sample to distinguish bulk and interface effects. Unintentional doping, the presence of charged impurities, degradation by deep hole traps and non-uniform interfacial layers could be all identified by carefully analysing current-voltage characteristics, partially with the help of numerical simulations solving the coupled nonlinear Poisson and drift-diffusion differential equations. Moreover, charge injection into selected green materials like plasticised films based on Buriti and Annatto oil revealed striking differences compared to the reference material P3HT, most likely related to interface modifications. The given example proves the usefulness of establishing charge injection into casted P3HT film as control when developing green materials for electronic applications.

The present study reports the results obtained from Sewage Sludge SS for the obtainment of bio-oil through the pyrolysis process. The research aimed to evaluate the thermal and kinetic behavior of the bio-solid. In this work studies were made on physicochemical, elemental analysis (CHNO). Thermogravimetry (TG) with heating rate of 10o C min-1 over two atmospheres (synthetic air and N2), Thermodynamics (ΔH, ΔS e ΔG), kinetic and spectroscopic. The thermalgravimetric study stated a thermal stability at 30°C. The kinetic calculations were made aiming to observe parameters such as: Activation energy (Ae), frequency factor (s-1), standard deviation (sd) and linear coefficient (r), which were calculated by Thermogravimetry by the methods of Coats-Redfern (CR); Madhusudanan (MD); Van Krevelen (VK); Horowitz-Metzger (HM). In the spectrometry in the infrared (IR) region it was observed bands referring to the presence of water, organic material and silicon oxides in the SS samples analyzed.

The development of technologies that use clean energy and integrated waste management of the residues domestic and industrial aimed a sustainable engineering in the socio-business concepts is an urgent necessity. This present paper has as objective the production of cement composites trace 1:1,2:0,8 (cement : dust stone: gravel) replacing the sand and dust stone for PET waste in the levels of 3, 6, 9, 12 and 15 %, to evaluate the aging time. The materials were characterized using thermal analysis, FTIR and the composites by particle size analysis, unconfined compression strength, among others. The particle size analysis allowed the calculation of fineness modulus, which was 2.59, 1.66, and 3.99 for the dust stone, gravel and PET, respectively. There was a decreasing trend of resistance with the PET increasing in the composition.