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arXiv · 2409.06410

LaB6 aided spontaneous conversion of bulk graphite into carbon nanotubes at normal atmospheric conditions

Shalaka A. Kamble·Soumen Karmakar·Somnath R. Bhopale·Sanket D. Jangale·Neha P. Gadke·Srikumar Ghorui·S. V. Bhoraskar·M. A. More·V. L. Mathe
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Abstract

Herein, we report a case study in which we saw the spontaneous conversion of commercial bulk graphite into LaB6 decorated carbon nanotubes (CNTs) under normal atmospheric conditions. The feedstock graphite was used as a hollow cylindrical anode filled with LaB6 powder and partially eroded in a DC electric-arc plasma reactor in pure nitrogen atmosphere. An unusual and spontaneous deformation of the plasma-treated residual anode into a fluffy powder was seen to continue for months when left to ambient atmospheric conditions. The existence of LaB6 decorated multi-walled CNTs at large quantity was confirmed in the as-generated powder by using electron microscopy, Raman spectroscopy and x-ray diffraction. The as-synthesized CNT-based large-area field emitter showed promising field-emitting properties with a low turn-on electric field of ~1.5 V per micrometer, and a current density of ~1.17 mA per square cm at an applied electric field of 3.24 V per micrometer.

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Shalaka A. Kamble, Soumen Karmakar, Somnath R. Bhopale, Sanket D. Jangale, Neha P. Gadke, Srikumar Ghorui, S. V. Bhoraskar, M. A. More, V. L. Mathe. 2024-09-10. LaB6 aided spontaneous conversion of bulk graphite into carbon nanotubes at normal atmospheric conditions. https://arxiv.org/abs/2409.06410

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