Mechanically induced built-in electric field in BCTZ nanostructures for piezocatalysis: Experiments and modeling

Ba(Ti_0.80Zr_0.20)O₃–0.5(Ba_0.7Ca_0.3)TiO₃ (BCTZ) piezoelectric nanofibers (NFs) and nanoparticles (NPs) were fabricated using electrospinning and sol-gel methods, respectively. The impact of BCTZ nanostructure on piezocatalysis was investigated, revealing that both poled NFs and NPs exhibit a piezocatalytic degradation rate of 2.8 × 10^–2 min^-1, which is significantly higher than their unpoled counterparts at 2.3 × 10^–2 min^-1 and 1.9 × 10^–2 min^-1, respectively. The enhanced piezocatalytic degradation rates of the poled BCTZ nanostructures are attributed to their superior piezoelectricity, resulting in larger built-in electric fields under external strain. Moreover, BCTZ NFs provide numerous active piezocatalytic reaction sites confined to the one-dimensional (1D) fibrous boundaries. Simulation results indicate that BCTZ NFs exhibit greater displacement and higher piezoresponse compared to nanoparticles, due to the electromechanical coupling effect facilitated by the 1D nanostructure. This study provides an efficient pathway to understanding the coupling mechanism between the poled built-in electric field and piezotronics.