Synthesis of boron nitride nanotubes from unprocessed colemanite

Saban Kalay,Mustafa Çulha,Zehra Yilmaz

doi:10.3762/bjnano.4.95

Abstract

Colemanite (Ca2B6O11·5H2O) is a natural and new precursor material for the synthesis of boron nitride nanotubes (BNNTs). BNNTs have been synthesized from unprocessed colemanite for the first time. The reaction parameters such as time, catalyst type, catalyst amount and temperature were optimized. It was found that the BNNT formation follows the base growth mechanism, which was initiated with a complex of boron nitride (BN) and iron atoms. The obtained BNNTs were characterized by using SEM, TEM, and spectroscopic techniques such as UV–vis, Raman, FTIR and XRD. The BNNTs were randomly oriented and multi-walled with an outer diameter of 10–30 nm and a wall thickness of 5 nm. This novel BNNT synthesis method can be used to obtain high yield, low cost and pure BNNTs.

Highlights

Colemanite (Ca2B6O11·5H2O) is one of the most important compounds of more than 200 different boron ores
Amorphous boron has been preferred as the precursor boron compound to synthesize highyield boron nitride nanotubes (BNNTs) [5,27,28]
Colemanite as the most important of boron ores can be used for the synthesis of BNNTs since it contains B2O3 in its structure

Summary

Introduction

Colemanite (Ca2B6O11·5H2O) is one of the most important compounds of more than 200 different boron ores. The colemanite contains 50.8% B2O3 and is used in many applications including the fibre glass industry, the ceramic industry, the steel industry, boron alloys, and metallurgy. Another use of colemanite is the synthesis of boric acid (H3BO3) [2]. BNNTs, structural analogoues of carbon nanotube (CNT)s, have superior properties than CNTs due to their robust structure which resists high temperatures and harsh chemical conditions. They have a high hydrogen storage capacity due to the ionic nature of the B–N bond [5].

Methods

Results

Conclusion