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• SnO 2 and SnO 2 -Sb can considerably enhance the piezocatalytic efficiency. • SnO 2 acts as a DSA-like catalyst in the piezoelectric field of SnO 2 / t -BaTiO 3. • SnO 2 and SnO 2 -Sb can promote the generation of OH in the piezocatalysis. • Piezo-potential can also activate the free charges of the loaded SnO 2. Piezocatalysis is an emerging green advanced-oxidation technology for the degradation of toxic pollutants; however, piezomaterials are not generally excellent electrocatalysts. Herein, two complex piezocatalysts (SnO 2 / t -BaTiO 3 and SnO 2 -Sb/ t -BaTiO 3) consisting of an electrocatalyst and piezomaterial, respectively, are designed to investigate the coupled effect of piezocatalytic and electrocatalytic processes on the degradation of pollutants. SnO 2 , especially SnO 2 -Sb, can considerably enhance the piezocatalytic degradation of the antibiotic metronidazole (MNZ). The piezocatalytic rate constants of SnO 2 / t -BaTiO 3 and SnO 2 -Sb/ t -BaTiO 3 are 2.3 and 3.0 times that of t -BaTiO 3 , respectively. In the degradation process, SnO 2 and SnO 2 -Sb are confirmed to act as dimensionally stable anode-like (DSA-like) catalysts because they can increase the response of the piezoelectrochemical anodic current and the generation of OH radicals as well as reduce the formation of 1O 2. Significantly, the piezoelectric field can drive not only the free charges of t -BaTiO 3 and its remnant piezoelectric field but also those of the loaded electrocatalyst SnO 2 to participate in the degradation of MNZ. These results indicate that the coupling of an excellent electrocatalyst and piezomaterial is an effective method to promote piezocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Bis (2-hydroxyethyl) terephthalate (BHET) is one of the main compounds produced by enzymatic hydrolysis or chemical depolymerization of polyethylene terephthalate (PET). However, the lack of understanding on BHET microbial metabolism is a main factor limiting the bio-upcycling of PET. In this study, BHET-degrading strains of Rhodococcus biphenylivorans GA1 and Burkholderia sp. EG1 were isolated and identified, which can grow with BHET as the sole carbon source. Furthermore, a novel esterase gene betH was cloned from strain GA1, which encodes a BHET hydrolyzing esterase with the highest activity at 30 °C and pH 7.0. In addition, the co-culture containing strain GA1 and strain EG1 could completely degrade high concentration of BHET, eliminating the inhibition on strain GA1 caused by the accumulation of intermediate metabolite ethylene glycol (EG). This work will provide potential strains and a feasible strategy for PET bio-upcycling. • BHET-degrading strain Rhodococcus biphenylivorans GA1 and Burkholderia sp. EG1 were identified. • A novel esterase gene betH was cloned. • BetH has high catalytic activity for BHET. • Rhodococcus-Burkholderia consortium degrade high concentration BHET through mutualism. [ABSTRACT FROM AUTHOR]