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Today there is a strong interest in the scientific and industrial community concerning the use of biopolymers for
electronic applications, mainly driven by low-cost and disposable applications. Adding to this interest, we must
recognize the importance of the wireless auto sustained and low energy consumption electronics dream. This dream can
be fulfilled by cellulose paper, the lightest and the cheapest known substrate material, as well as the Earth's major
biopolymer and of tremendous global economic importance. The recent developments of oxide thin film transistors and
in particular the production of paper transistors at room temperature had contributed, as a first step, for the development
of disposable, low cost and flexible electronic devices. To fulfil the wireless demand, it is necessary to prove the concept
of self powered devices. In the case of paper electronics, this implies demonstrating the idea of self regenerated thin film
paper batteries and its integration with other electronic components. Here we demonstrate this possibility by actuating
the gate of paper transistors by paper batteries. We found that when a sheet of cellulose paper is covered in both faces
with thin layers of opposite electrochemical potential materials, a voltage appears between both electrodes -paper
battery, which is also self-regenerated. The value of the potential depends upon the materials used for anode and
cathode. An open circuit voltage of 0.5V and a short-circuit current density of 1μA/cm2 were obtained in the simplest
structure produced (Cu/paper/Al). For actuating the gate of the paper transistor, seven paper batteries were integrated in
the same substrate in series, supplying a voltage of 3.4V. This allows proper ON/OFF control of the paper transistor.
Apart from that transparent conductive oxides can be also used as cathode/anode materials allowing so the production of
thin film batteries with transparent electrodes compatible with flexible, invisible, self powered and wireless electronics.
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