Microstructuring of conductivity tuned piezoelectric polydimethylsiloxane/(Ba _0.85 Ca _0.15 )(Ti _0.90 Hf _0.10 )O ₃ composite for hybrid mechanical energy harvesting

Abstract Tuning of dipolar polarization, piezoelectricity, and conductivity of polydimethylsiloxane (PDMS) along with thin‐film microstructuring has been simultaneously utilized here to improve its piezo‐tribo hybrid mechanical energy harvesting performance. With this intention, a morphotropic phase boundary based highly piezoelectric (Ba 0.85 Ca 0.15 )(Ti 0.90 Hf 0.10 )O 3 (BCHT) filler has been incorporated into PDMS to develop flexible piezoelectric composite films. The conductivity of PDMS/BCHT composites has further been tuned by the addition of varied amounts of multi‐walled carbon nanotubes (MWCNTs). Piezoelectric nanogenerators (PENGs) and piezo‐tribo hybrid nanogenerators (HNGs) have then been developed based on these ternary composites. With the increase in conductivity of PDMS/BCHT films (via enhanced MWCNT addition), both the piezoelectric and hybrid energy harvesting performances of the corresponding nanogenerators improved significantly. Microstructuring of the optimized composite has then been done via optical lithography, which enhanced the output power density of the corresponding HNG from ~200 μW/cm 2 to almost ~500 μW/cm 2 . Highlights Polydimethylsiloxane (PDMS)/(Ba 0.85 Ca 0.15 )(Ti 0.90 Hf 0.10 )O 3 (BCHT) films were developed. Space charge polarization tuned via multi‐walled carbon nanotubes (MWCNTs) addition. Piezoelectric and hybrid nanogenerators (PENGs and HNGs) developed by the films. Tuning of charge defects improved the performance of developed devices. Microstructuring of the film further augmented the output performance of the HNG.