Preparation of Carbon Nanotube-Sulfur Nanohybrid Materials with Elemental Sulfur as a Feedstock

TL;DR

This paper describes a new method to create carbon nanotube-sulfur hybrids using sulfur as a feedstock, which can effectively absorb metal ions.

Contribution

A novel two-step process using PGMA functionalization and inverse vulcanization to enhance metal ion absorption in CNT-sulfur hybrids.

Findings

CNT-sulfur nanohybrids with 23.2 wt% polysulfide segments were produced via direct addition reaction.

PGMA-functionalized CNTs showed 31.3 wt% polysulfide segments after inverse vulcanization.

Route 2 hybrids absorbed 16 mg g−1 of Fe3+, significantly higher than previous sulfur polymers.

Abstract

Based on the concept of green chemistry and synthesis
of new functional
materials, elemental sulfur is employed as the feedstock for the preparation
of nanohybrid materials of carbon nanotubes (CNT) and sulfur. Referring
to the radical reaction-based inverse vulcanization process, 2 reaction
routes are conducted in this work. In the first approach elemental
sulfur is directly reacted with CNTs through the addition reaction
between sulfur radicals and the CC bonds of CNT surfaces.
The obtained CNT-sulfur nanohybrids possess 23.2 wt % polysulfide
segments chemically bonded to the outer surfaces of CNTs. The second
route involves 2-step reactions, including the incorporation of poly­(glycidyl
methacrylate) (PGMA) to CNTs through a surface-initiated atom transfer
radical polymerization followed by an inverse vulcanization reaction
between the PGMA-functionalized CNTs and elemental sulfur. 31.3 wt
% polysulfide segments are chemically bonded to the PGMA-functionalized
CNTs. The CNT-sulfur nanohybrids are subjected to metal ion absorption.
The sample from route 2 exhibits an absorption capacity of 16 mg g−1 for Fe3+, which is several times higher
than the values reported for sulfur polymers from inverse vulcanization.
The inverse vulcanization-like process provides an effective platform
for the synthesis of CNT-sulfur nanohybrids exhibiting high absorption
capacity for metal ions.

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