Influence of pore morphologies on the mechanical and tribo-electrical performance of polydimethylsiloxane sponge fabricated via commercial seasoning templates

Abstract

This work demonstrated the influence of pore morphologies on the mechanical behavior and tribo-electrical performance of fabricated polydimethylsiloxane (PDMS) sponge. Commercial seasonings with different 3D geometric shapes were used as a sacrificial template to control the pore structure of the PDMS sponge. The result indicated that the softest PDMS sponge was molded by using a sodium chloride (NaCl) crystal template, as indicated by the lowest compressive modulus value. Then, P(VDF–HFP) was incorporated into PDMS prepolymer in order to enhance the charge generation characteristic of PDMS. Besides, the composite 3D structure was revealed using synchrotron radiation X-ray tomographic microscopy (SRXTM). Interpretation from the SRXTM result confirmed that the porous structure had different pore shapes, i.e., an octahedral-like shape and a circular-like shape in a particular sponge. By pairing the composite PDMS sponge with an aluminum (Al) plate for the triboelectric nanogenerator (TENG), the maximum electrical outputs of ~29.9 V and ~0.56 μA for voltage and current, respectively, were detected with loading 50 wt% of P(VDF – HFP). The presented TENG was applied successfully for sensing basic human activities practically, which demonstrated potential applications in wearable electronics.