Smart polydimethylsiloxane sponges with high piezoelectric responses

Abstract

In recent years, soft and stretchable electrets have drawn considerable attention for their wide applications in energy harvesters, sensors, and actuators. However, existing electrets struggle to attain both longevity and stretchability (softness), which means charge retention capability and stretchability (softness) of electrets conflict. In this article, one novel soft and stretchable electret (PPSE) with great electromechanical performance is demonstrated. The PPSE is composed of a polydimethylsiloxane (PDMS) sponge and polytetrafluoroethylene (PTFE) particles. The uniformly distributed pores obtained by the sugar leaching method inside the PPSE can not only accumulate macroscopic dipoles but also provide great stretchability, flexibility, and softness for the material. The resulting PPSE has a large d33italiceff value up to 477 pC/N and great charge stability. Moreover, by the virtue of stretchability and softness, it can output electric signals from twisting, bending, and other mechanical interactions without breaking apart. With these great performances, PPSE will potentially enable applications for actuation, sensing, and energy harvesting.

A Stretchable Expanded Polytetrafluorethylene-Silicone Elastomer Composite Electret for Wearable Sensor

“…The combination of Ecoflex matrix and ePTFE gives rise to the improved comprehensive mechanical properties of the composite electret because of the excellent stretchability, low elastic modulus, and low hysteresis of Ecoflex elastomer ( Figure S5b,e ). In comparison with the recently reported research [ 5 , 6 , 9 , 17 , 20 , 22 , 26 ], the ePTFE/Ecoflex composite electret exhibits superior performance in terms of stretchability and longevity. Therefore, a composite electret with longevity, high charge density, and robust comprehensive mechanical properties is achieved, which can be potentially applicable to constructing self-powered flexible electronic devices.…”

“…Although both stretchability and longevity were achieved in this electret film, the strain and stretch direction also restrict its applications. A straightforward approach has been proposed to improve the longevity of elastomer electrets, which is to introduce the inorganic nanoparticles or hard plastic nanoparticles, e.g., silica nanoparticles [ 9 ] and PTFE nanoparticles [ 22 ], into the elastomer matrix. Suo et al [ 9 ] reported a stretchable electret based on silica nanoparticles filled polydimethylsiloxane, which provided a charge density of 4 × 10 −5 C m −2 and a lifetime beyond 60 days.…”

High removal of chlorinated solvents by reusable polydimethylsiloxane based absorbents

“…[14,15] Sugar, crystal salts, and oxides have been used as templates. [16][17][18][19][20] The use of ZnO nanoparticles as templates appears as an interesting possibility since it has been reported as template for triboelectric nanogenerators [16] and, but its application as generators of pores for sponges has not been fully explored.…”