Preparation of a PANI/ZnO Composite for Efficient Photocatalytic Degradation of Acid Blue.

Vanja Gilja,Zlata Hrnjak-Murgić,Mark Žic,Ivan Vrban,Vilko Mandić

doi:10.3390/polym10090940

Vanja Gilja, Zlata Hrnjak-Murgić + Show 3 more

Open Access

https://doi.org/10.3390/polym10090940

Copy DOI

Journal: Polymers	Publication Date: Aug 23, 2018
Citations: 68	License type: CC BY 4.0

Affiliation: University of Zagreb, Rudjer Boskovic Institute

Abstract

Polyaniline/zinc oxide (PANI/ZnO) composite photocatalysts were prepared from neutral media by in situ chemical oxidation of aniline (ANI) in the presence of different amounts of diethylene glycol (DEG). The PANI/ZnO composite photocatalysts were synthesized to efficiently remove organic dye (acid blue, AB25) from model wastewater. The PANI/ZnO composite photocatalysts were studied with the intention of efficient removal of organic dye (acid blue, AB25) from wastewater to obtain low-cost heterogeneous catalysts that offer high catalytic activity and stability. The conductive PANI polymer, which absorbs Vis irradiation, was used in this work as ZnO absorbs only ultraviolet (UV) irradiation; thus, the composite photocatalysts’ activity was broadened into the Vis region. Characterization of the composite photocatalysts was done by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, electric conductivity, UV-Vis spectroscopy, and by specific surface area (SBET) measurements. The composites’ photocatalytic activity under solar irradiation was validated by monitoring degradation of the AB25 dye. This study presented that it was possible both to prepare PANI and to prevent ZnO dissolution if in situ polymerization starts from neutral media with the addition of DEG. Additionally, efficient removal of AB25 dye, about 90% in 60 min, was achieved. The first-order rate constants of the photodegradation of AB25 by PANI/ZnO 0.02/0.024/0.04 DEG (and pure ZnO)) were computed to be 0.0272/0.0281/0.0325 (and 0.0062) min−1, indicating that the morphology and surface of the photocatalysts have significantly influenced the catalytic activity.

Highlights

Increased awareness regarding a material’s performance and increased competition in the global market for polymer composites have fueled their growth
Fourier transform infrared (FTIR) spectra of pure PANI, Zinc oxide (ZnO) and PANI/ZnO composites are given in Figure 1, in which the most prominent absorption bands correspond to the PANI polymer
The absorption intensity ratio of PANI bands (1583 and 1494 cm−1 ) typical for quinoid (Q) and benzoid (B) units is 1:3. This ratio is in accordance to the Q versus B units ratio (1:3) in Scheme 2 [37]), which indicates that PANI (Figure 1) is in a conductive form

Summary

Introduction

Increased awareness regarding a material’s performance and increased competition in the global market for polymer composites have fueled their growth. Composites (i.e., the wonder materials) are becoming an essential part of today’s materials due to the construction of more complex hybrid materials. Nanoarchitectonics is an emerging field that refers to the rational design and construction of nanostructures into functional materials with control at the nanoscale [1,2,3]. Composites can be defined as materials consisting of two or more chemically and physically different phases that are separated by a distinct interface. Different materials are combined judiciously to achieve a system (i.e., composite) with more useful structural or functional properties that are unattainable by any of the constituents alone

Objectives

Methods

Results

Conclusion