Self-Powered Wearable Piezoelectric Sensors Based on Polymer Nanofiber–Metal–Organic Framework Nanoparticle Composites for Arterial Pulse Monitoring

Abstract

High-performance wearable electronic devices with the capability of converting mechanical force into electrical energy have been gaining increasing attention for biomedical monitoring applications. We present a novel wearable piezoelectric sensor based on a poly­(vinylidene fluoride) (PVDF) nanofibrous membrane containing microporous zirconium-based metal–organic frameworks (MOFs) for arterial pulse monitoring. It is shown that the incorporation of 5 wt % of MOF greatly enhances the piezoelectric constant of the polymer fibrous mat by 3.4-fold without significant loss in its flexibility. The nanofibrous composite exhibits a peak-to-peak voltage of 600 mV under an applied force of 5 N, which is superior to many flexible pressure sensors. It is demonstrated that the enhanced piezoelectric performance of the nanofibrous composite is not only attributed to the increased degree of crystallinity and polar β phase content (75%) but also to the surface chemistry and topography of the nanofibers. Evaluations of the piezoelectric output of the sensor attached to the radial artery at normal body conditions reveal significantly better output voltage (568 ± 76 mV) and sensitivity (0.118 V/N) than nanofibrous PVDF devices for wrist pulse monitoring. The results of this work pave a new way to develop flexible piezoelectric nanofibrous sensors based on MOFs for environmentally sustainable energy generation and wearable healthcare monitoring systems.

Highly efficient fluorescent chemosensor for nitro antibiotic detection based on luminescent coordination polymers with 2,6-di(4-carboxyphenyl)pyrazine

“…The emergence of porous coordination polymers (PCPs) with unprecedented diversity in structures and functions has become a significant materials chemistry achievement over the past two decades. Crystalline materials' porosity and tailored functionality have attracted extensive attention in application areas of gas storage, [1][2][3] separation, [4][5][6] luminescence, [7][8][9] piezoelectricity, [10][11][12] catalysis, [13][14][15] magnetism, [16][17][18] biomedicine, [19][20][21] sensors, [22][23][24] and so on. Considering their large specific surface area, adjustable pore size, and surface chemical sites, compared to all the applications, exploring the potential use of PCPs as chemical sensors has broad application prospects and extraordinary significance.…”

An Insight into Tunable Innate Piezoelectricity of Silk for Green Bioelectronics

“…Biocompatible and highly stable zirconium-based MOF (UiO66) was used to functionalize the PVDF nanofibers to increase the β crystalline phase by increasing the loading of nanoparticles while developing highly flexible membranes. [45] The MOF modified PVDF membrane yielded a maximum output voltage of 568 mV at 5 wt.% of MOF on using the device for arterial pulse monitoring. The high piezoelectric response was due to nano-porous structure of the membranes with a high β crystalline content of 64 %.…”

Metal-organic frameworks as functional materials for implantable flexible biochemical sensors

“…9(a) and 9(b)). Simchi and coworkers presented a novel flexible piezoelectric sensor based on a poly(vinylidenefluoride) (PVDF) nanofibrous/UiO-66 composite for arterial pulse monitoring [348]. The UiO-66based sensor was obtained by electrospinning PVDF/ UiO-66 suspension onto an aluminum collecting drum, followed by sandwiching the collected composite between two Cu-sputtered aluminum foils.…”