Controllable preparation of semiconducting polymer microspheres and their application in the photocatalytic degradation of tetracycline antibiotics

Abstract

The side effects of antibiotics on humans and ambient environment have aroused huge attention from related researchers. In this article, the performances and mechanism of photodegradation of tetracycline (TC) were examined by employing semiconducting polymer microspheres obtained with an emulsion-solvent-evaporation approach. Under the excitation of visible-light, as-prepared semiconducting polymer microspheres show outstanding photocatalytic ability and excellent stability for TC-derived antibiotics. Compared with corresponding semiconducting polymer powders, the adsorption and photocatalytic rates of TC by polymer-based microspheres increased by 8.07 and 6.79 times, respectively. These performance improvements in photodegradation are mainly ascribed to the larger specific surface area and longer conjugation length of as-prepared spherical structure. Characterization of electron spin resonance demonstrates that the primary active species functioning for efficient photodegradations of TC are superoxide radical, hydrogen peroxide, and hole. These results indicated that semiconducting polymer microspheres can serve as efficient photocatalysts for removing destructive TC-derived antibiotics from wastewaters.

Graphical abstract

KEYWORDS:

• Semiconducting polymers
• microspheres
• photocatalysts
• tetracycline antibiotics