A high-performance magneto-mechano-triboelectric nanogenerator (MMTEG) was demonstrated by introducing accelerated water-soluble nano-bullet modified nanostructures to convert a gentle magnetic field into electric energy for powering an indoor wireless positioning system. NaCl salt nanoparticles were accelerated by an aerosol deposition (AD) process to collide on a perfluoroalkoxy (PFA) film with a high kinetic energy for the formation of a complicated nanomorphology on the triboelectric active surface. Under an alternating current (AC) magnetic field of 7 Oe, the MMTEG generated an open-circuit peak-to-peak voltage (Vpp) and a short-circuit current of 708 V and 277 μA, respectively. The harvesting device also presented a maximum peak power of 21.8 mW as well as a continuous AC output power of 4.8 mW (4.8 mJ per second). A self-powered indoor IoT positioning system was constructed by integrating the MMTEG, a power managing circuit, a storage element, and an IoT Bluetooth beacon. The electric energy from the MMTEG device enabled continuous operation of a beacon device, and we successfully confirmed the accurate location of the installed wireless positioning system, subsequently resulting in transmission of our indoor position to the main monitoring computer. Lastly, the MMTEG generated an open-circuit Vpp and a short-circuit current of 330 V and 23 μA, respectively, near a 60 Hz power cable connected to home appliances, which were large enough to turn on 108 blue light emitting diodes (LEDs).
By tailoring the truncated shape of a cantilever structured magneto-mechano-electric (MME) generator that is composed of a piezoelectric single crystal fiber composite and a magnetostrictive Ni plate, a superior output harvesting power density of over 680% was obtained as compared to a typical rectangular shaped generator. The effect of the MME generator's shape on the strain distribution induced by magnetostriction and vibration characteristics and harvesting properties were simulated by finite element analysis modeling and confirmed experimentally, respectively. The truncated shape was effective for not only utilizing a more uniform in-plane strain distribution in the active piezoelectric area but also magnifying the flexural vibration amplitude, which in turn can make the generator more powerful under tiny magnetic oscillations.
Numerical results for the energy spectra of electrons on a spherical surface are used as input data to determine the quasiparticle energies and the pairwise "Fermi liquid" interactions of composite fermion (CF) excitations in fractional quantum Hall systems. The quasiparticle energies and their interactions are then used to determine the energy spectra, vs total angular momentum , of states containing more than two quasiparticles. The qualitative agreement with the numerical results gives a remarkable new confirmation of the CF picture.
In this paper, we demonstrated a multiscale micro- and nano-structured magneto-mechano-triboelectric nanogenerator (MMTENG) enabled by a salt particle imprinting process to power an internet of thing (IoT) sensor. The fine salt particles were utilized to form a multiscale structure on a triboelectric polymer film by mechanical pressure via an eco-friendly, low-cost, and simple process, thereby reinforcing the contact triboelectrification and electrostatic induction. The surface modified MMTENG can generate an open-circuit peak-to-peak voltage of 851 V, a short-circuit current of 155 μA, and a maximum peak power of 10.3 mW under an AC magnetic field of 8 Oe. The energy device also presented output stability over 124 million operating cycles. Finally, the electricity of the surface enhanced MMTENG device was directly utilized to power an IoT temperature sensor with integration of an energy harvester, energy conversion circuit, and storage capacitor.
4 December 2015 in The Journal of Physical Chemistry C