5 research outputs found
Design of In Situ Poled Ce<sup>3+</sup>-Doped Electrospun PVDF/Graphene Composite Nanofibers for Fabrication of Nanopressure Sensor and Ultrasensitive Acoustic Nanogenerator
We
report an efficient, low-cost in situ poled fabrication strategy to
construct a large area, highly sensitive, flexible pressure sensor
by electrospun Ce<sup>3+</sup> doped PVDF/graphene composite nanofibers.
The entire device fabrication process is scalable and enabling to
large-area integration. It can able to detect imparting pressure as
low as 2 Pa with high level of sensitivity. Furthermore, Ce<sup>3+</sup>-doped PVDF/graphene nanofiber based ultrasensitive pressure sensors
can also be used as an effective nanogenerator as it generating an
output voltage of 11 V with a current density ∼6 nA/cm<sup>2</sup> upon repetitive application of mechanical stress that could
lit up 10 blue light emitting diodes (LEDs) instantaneously. Furthermore,
to use it in environmental random vibrations (such as wind flow, water
fall, transportation of vehicles, etc.), nanogenerator is integrated
with musical vibration that exhibits to power up three blue LEDs instantly
that promises as an ultrasensitive acoustic nanogenerator (ANG). The
superior sensing properties in conjunction with mechanical flexibility,
integrability, and robustness of nanofibers enabled real-time monitoring
of sound waves as well as detection of different type of musical vibrations.
Thus, ANG promises to use as an ultrasensitive pressure sensor, mechanical
energy harvester, and effective power source for portable electronic
and wearable devices
An Effective Electrical Throughput from PANI Supplement ZnS Nanorods and PDMS-Based Flexible Piezoelectric Nanogenerator for Power up Portable Electronic Devices: An Alternative of MWCNT Filler
We demonstrate the requirement of
electrical poling can be avoided in flexible piezoelectric nanogenerators
(FPNGs) made of low-temperature hydrothermally grown wurtzite zinc
sulfide nanorods (ZnS-NRs) blended with polydimethylsiloxane (PDMS).
It has been found that conductive fillers, such as polyaniline (PANI)
and multiwall carbon nanotubes (MWCNTs), can subsequently improve
the overall performance of FPNG. A large electrical throughput (open
circuit voltage ∼35 V with power density ∼2.43 μW/cm<sup>3</sup>) from PANI supplement added nanogenerator (PZP-FPNG) indicates
that it is an effective means to replace the MWCNTs filler. The time
constant (Ï„) estimated from the transient response of the capacitor
charging curves signifying that the FPNGs are very much capable to
charge the capacitors in very short time span (e.g., 3 V is accomplished
in 50 s) and thus expected to be perfectly suitable in portable, wearable
and flexible electronics devices. We demonstrate that FPNG can instantly
lit up several commercial Light Emitting Diodes (LEDs) (15 red, 25
green, and 55 blue, individually) and power up several portable electronic
gadgets, for example, wrist watch, calculator, and LCD screen. Thus,
a realization of potential use of PANI in low-temperature-synthesized
ZnS-NRs comprising piezoelectric based nanogenerator fabrication is
experimentally verified so as to acquire a potential impact in sustainable
energy applications. Beside this, wireless piezoelectric signal detection
possibility is also worked out where a concept of self-powered smart
sensor is introduced
Cerium(III) Complex Modified Gold Electrode: An Efficient Electrocatalyst for the Oxygen Evolution Reaction
Exploring efficient
and inexpensive electrocatalysts for the oxidation of water is of
great importance for various electrochemical energy storage and conversion
technologies. In the present study, a new water-soluble [Ce<sup>III</sup>(DMF) (HSO<sub>4</sub>)<sub>3</sub>] complex was synthesized and
characterized by UV–vis, photoluminescence, and high-resolution
X-ray photoelectron spectroscopy techniques. Owing to classic 5d →
4f transitions, an intense photoluminescence in the UV region was
observed from the water-soluble [Ce<sup>III</sup>(DMF) (HSO<sub>4</sub>)<sub>3</sub>] complex. A stacking electrode was designed where self-assembled l-cysteine monolayer modified gold was immobilized with the
synthesized cerium complex and was characterized by scanning electron
microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry.
The resulting electrode, i.e., [Ce<sup>III</sup>(DMF) (HSO<sub>4</sub>)<sub>3</sub>]–l-cysteine-Au stacks shows high electrocatalytic
water oxidation behavior at an overpotential of η ≈ 0.34
V under neutral pH conditions. We also demonstrated a way where the
overpotential is possible to decrease upon irradiation of UV light
DNA-Assisted β‑phase Nucleation and Alignment of Molecular Dipoles in PVDF Film: A Realization of Self-Poled Bioinspired Flexible Polymer Nanogenerator for Portable Electronic Devices
A flexible nanogenerator (NG) is
fabricated with a polyÂ(vinylidene fluoride) (PVDF) film, where deoxyribonucleic
acid (DNA) is the agent for the electroactive β-phase nucleation.
Denatured DNA is co-operating to align the molecular −CH<sub>2</sub>/–CF<sub>2</sub> dipoles of PVDF causing piezoelectricity
without electrical poling. The NG is capable of harvesting energy
from a variety of easily accessible mechanical stress such as human
touch, machine vibration, football juggling, and walking. The NG exhibits
high piezoelectric energy conversion efficiency facilitating the instant
turn-on of several green or blue light-emitting diodes. The generated
energy can be used to charge capacitors providing a wide scope for
the design of self-powered portable devices
Self-Poled Transparent and Flexible UV Light-Emitting Cerium Complex–PVDF Composite: A High-Performance Nanogenerator
CeriumÂ(III)-<i>N</i>,<i>N</i>-dimethylformamide-bisulfate
[CeÂ(DMF)Â(HSO<sub>4</sub>)<sub>3</sub>] complex is doped into polyÂ(vinylidene
fluoride) (PVDF) to induce a higher yield (99%) of the electroactive
phases (β- and γ-phases) of PVDF. A remarkable enhancement
of the output voltage (∼32 V) of a nanogenerator (NG) based
on a nonelectrically poled ceriumÂ(III) complex containing PVDF composite
film is achieved by simple repeated human finger imparting, whereas
neat PVDF does not show this kind of behavior. This high electrical
output resembles the generation of self-poled electroactive β-phase
in PVDF due to the electrostatic interactions between the fluoride
of PVDF and the surface-active positive charge cloud of the cerium
complex via H-bonding and/or bipolar interaction among the opposite
poles of cerium complex and PVDF, respectively. The capacitor charging
capability of the flexible NG promises its applicability as piezoelectric-based
energy harvester. The ceriumÂ(III) complex doped PVDF composite film
exhibit an intense photoluminescence in the UV region, which might
be due to a participation of electron cloud from negative pole of
bipolarized PVDF. This fact may open a new area for prospective development
of high-performance energy-saving flexible solid-state UV light emitters