Nanogenerators and self-powered nanosensors have shown the potential to power
low-consumption electronics and human-machine interfaces, but their practical
implementation requires reliable, environmentally friendly and scalable,
processes for manufacturing and processing. This article presents a plasma
synthesis approach for the fabrication of piezoelectric nanogenerators (PENGs)
and self-powered sensors on paper substrates. Polycrystalline ZnO nanocolumnar
thin films are deposited by plasma-enhanced chemical vapour deposition on
common paper supports using a microwave electron cyclotron resonance reactor
working at room temperature yielding high growth rates and low structural and
interfacial stresses. Applying Kinetic Monte Carlo simulation, we elucidate the
basic shadowing mechanism behind the characteristic microstructure and porosity
of the ZnO thin films, relating them to an enhanced piezoelectric response to
periodic and random inputs. The piezoelectric devices are assembled by
embedding the ZnO films in PMMA and using Au electrodes in two different
configurations: laterally and vertically contacted devices. We present the
response of the laterally connected devices as a force sensor for low-frequency
events with different answers to the applied force depending on the impedance
circuit, i.e. load values range, a behaviour that is theoretically analyzed.
The vertical devices reach power densities as high as 80 nW/cm2 with a mean
power output of 20 nW/cm2. We analyze their actual-scenario performance by
activation with a fan and handwriting. Overall, this work demonstrates the
advantages of implementing plasma deposition for piezoelectric films to develop
robust, flexible, stretchable, and enhanced-performance nanogenerators and
self-powered piezoelectric sensors compatible with inexpensive and recyclable
supportsComment: 30 pages, 8 figures in main tex