Cover Picture: Phys. Status Solidi C 12/2015

Sustainability became a concern when developing new low cost electronic products able to establish new markets or complement the existing ones. When thinking on low cost and sustainable electronic systems, a bio‐polymer such as cellulose can be considered as an interesting option to be used not only as substrate but also as a component of such systems. Taking this into consideration, giving cellulose based materials proper electronic functionalities is nowadays a hot topic. In their work, D. Gaspar and co‐authors (pp. 1421–1426) have tailored paper samples in order to be used simultaneously as substrate and gate dielectric material in oxide based field effect transistors (FETs). It was observed that the gate leakage current and environmental stability in these devices depend directly on fibril's dimension, morphology and arrangement, where the best results were obtained for micro/nano fibrillated cellulose paper samples. Moreover, extra ionic charge added to the cellulose during paper samples preparation results in the improvement of FETs' electrical characteristics, with saturation mobility reaching 16 cm 2 V –1 s –1 and on/off current ratio close to 10 5 .