Effect of the aromatic precursor flow rate on the morphology and properties of carbon nanostructures in plasma enhanced chemical vapor deposition

K Lehmann,O Yurchenko,G Urban

doi:10.1039/c6ra02999j

Abstract

Understanding the effects of the synthesis parameters on the morphology and electrochemical properties of nanocarbon layers is a key step in the development of application-tailored nanostructures.

Highlights

Carbon materials have long been established as electrode materials in diverse electrochemical applications, such as batteries, fuel cells, supercapacitors, for several reasons.[1,2,3] Graphite, the most famous carbon material with sp[2] hybridization, is low-priced and offers good electrical conductivity and high chemical stability which make it a great electrode material
The enhancement of surface area in activated carbon is accompanied with increasing of porosity which leads to poorer electrical conductivity of the layers restricting its widespread utilization in diverse electrochemical devices or aFreiburg Materials Research Centre (FMF), University of Freiburg, Freiburg, Germany bDepartment of Microsystems Engineering (IMTEK), Laboratory for Sensors, University of Freiburg, Freiburg, Germany
The variation of the liquid precursor ow rate in the range of 0.5 to 5 ml hÀ1 leads to the formation of three different morphologies, carbon nano bers (CNF), freestanding carbon nanowalls and interconnected carbon nanowalls

Summary

Introduction

The plasma enhanced chemical vapor deposition (PECVD) method represents a promising approach for stepwise growth of vertically aligned carbon nanostructures of different shapes. Understanding the effect of synthesis parameters on the nanoscale/mesoscale structure, as well as the electrochemical properties of nanostructured carbons, are indispensable preconditions to achieve electrode performance maximization, contributing to successful implementation in energy devices and sensors. The CN were grown using inductively coupled plasma enhanced chemical vapor deposition (IC-PECVD) without a catalyst and with aromatic p-xylene as a carbon precursor. The substrate was chosen to be precleaned silicon wafer pieces coated with titanium nitride They were mounted on metal plates, which were xed to a cylindrical metal grid in the reactor. Scanning electron microscopy (SEM) (Quanta 250 FEG), transmission electron microscopy (TEM) (Zeiss LEO 912), Raman spectroscopy (Olympus BX40) and X-ray Photoelectron

Material and methods

Results and discussion

Conclusions