Synthesis of titanate nanofibers co-sensitized with ZnS and Bi2S3 nanocrystallites and their application on pollutants removal

TL;DR

This study reports the synthesis of titanate nanofibers co-sensitized with ZnS and Bi2S3 nanocrystallites, demonstrating their effective photocatalytic and adsorptive capabilities for removing organic pollutants like methylene blue.

Contribution

It introduces a novel method for creating nanocomposite materials combining titanate nanofibers with ZnS and Bi2S3, enhancing pollutant removal through combined adsorption and photocatalysis.

Findings

Nanocomposites successfully synthesized with ZnS and Bi2S3 on titanate nanofibers.

All samples showed photocatalytic ability for hydroxyl radical production.

Bi2S3ZnS/TNF exhibited the highest removal efficiency for methylene blue.

Abstract

The synthesis of nanocomposite materials combining titanate nanofibers (TNF) with nanocrystalline ZnS and Bi2S3 semiconductors is described in this work. The TNF were produced via hydrothermal synthesis and sensitized with the semiconductor nanoparticles, through a single-source precursor decomposition method. ZnS and Bi2S3 nanoparticles were successfully grown onto the TNF's surface and Bi2S3-ZnS/TNF nanocomposite materials with different layouts were obtained using either a layer-by-layer or a co-sensitization approach. The samples' photocatalytic performance was first evaluated through the production of the hydroxyl radical using terephthalic acid as probe molecule. All the tested samples show photocatalytic ability for the production of this oxidizing species. Afterwards, the samples were investigated for the removal of methylene blue. The nanocomposite materials with best adsorption ability for the organic dye were the ZnS/TNF and Bi2S3ZnS/TNF. The removal of the methylene blue was systematically studied, and the most promising results were obtained considering a sequential combination of an adsorption-photocatalytic degradation process using the Bi2S3ZnS/TNF powder as a highly adsorbent and photocatalyst material.