Novel polyaniline/tungsten trioxide@metal–organic framework nanocomposites for enhancing photodegradation of 4-nitrophenol

Abstract

Abstract Novel photocatalysts polyaniline/tungsten trioxide (P/W), polyaniline/tungsten trioxide @zeolitic imidazolate frameworks, (P/W@ZIF-8) and polyaniline/tungsten trioxide@ Zr(IV) aminoterephthalate metal–organic frameworks (P/W@UiO-66-NH2 MOFs) were successfully synthesized via the in-situ growth of polyaniline, ZIF-8, and UiO-66-NH 2 MOFs onto the tungsten trioxide nanoparticle. The synthesized photocatalysts have been characterized using XRD, FT-IR, FESEM, TEM, EDX, BET, UV–vis and PL techniques. The P/W, P/W@ZIF-8 and P/W@UiO-66-NH2 composites show the best degradation efficiency for 4-nitrophenol (4-NP) with an apparent rate constants value of 0.01439, 0.0319 and 0.0500 min − 1 , respectively, that is 19, 42.3 and 66.3 times as greater as that of pristine WO3 (7.54 × 10 − 4 min − 1 ). Typically, 20 ppm of the 4-NP solution was degraded completely and 95.8% of the carbon content had been mineralized in 180 min at 25 °C using 0.5 g/L of the P/W@UiO-66-NH2 nanocomposite. The remarkable improvement of catalytic activity and photostability could be due to the synergetic effect between tungsten trioxide, polyaniline, and metal–organic frameworks. Based on the quenching tests, • OH and • O 2 − were referred to be the main effective species. Reusability experiments of photocatalyst demonstrated that the photocatalyst displays excellent stability and reusability.