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International Journal of Bioprinting High-performance electrospun PVDF/AgNP/Mxene fiber

Figure 7. Applications of PVDF/MXene/AgNP composite as a self-powered sensor for the detection of human motion. Voltage outputs of the sensor de-
tecting the (A) clapping of hands, (B) moving of arms, (C) moving of fingers, and (D) walking.
The gloves were first attached with fabricated nanofiber thereby improving the piezoelectric characteristics
mats, and the voltage output was then monitored when of the whole fiber. The output voltages when clapping
clapping hands, thereby converting hand pressure into hands, moving arms, moving a finger, and walking were
electricity (Figure 7A). The voltage output was measured 15, 7.5, 4, and 11 V, respectively. When the hands were
when clapping hands at different frequencies. Figure 8 moved, as displayed in Figure 8C and D, voltage peaks of
reveals that the consecutive clapping of hands resulted in up to 14–15 V were recorded, as a result of the pressure
voltage responses that were recoverable and steady. More imparted to the sensor site while being touched. In
notably, when a person clapped his or her hands, first slowly, view of the irregularity of the forces applied, there were
and then quickly, the output voltage frequency reacted in variations in the sizes of the voltage peaks. The PVDF/
a manner consistent with the movement, indicating good AgNP/MXene fibers exhibited exceptional stability and
synchronization. Subsequently, sensors were connected excellent output performance, enabling their use for
to the underarm of clothing and to the medial elbow energy harvesting and powering LEDs. Figure 9 reveals
(Figure 7B). The sensors detected the movement of the arms the ability of the sensor to power an LED through the
and converted the arm pressure into electricity, resulting in touch of a finger.
a series of voltage signals. When we attached the sensor In order to evaluate the sensing ability of the optimized
to a finger, it detected finger movements, converting finger PVDF/AgNP/MXene composite piezoelectric sensor,
pressure into electricity (Figure 7C). In addition, walking we coupled it with a circuit integrated with an Arduino
was detected by a sensor attached to the ground, converting microcontroller (Mega 2560). Arduino is a hardware
leg pressure into electricity (Figure 7D). The output voltages platform used for the development of applications based
provided repeatable, steady, and synchronous signals.
on Atmel microcontrollers. The Mega 2560 model,
The presence of AgNP/MXene composite in PVDF which we applied in this study, is a standard commercial
also enhanced the electrical conductivity of the material, board entrusted to acquiring and recording inputs. The

Volume 9 Issue 1 (2023)olume 9 Issue 1 (2023) 346 https://doi.org/10.18063/ijb.v9i1.647
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