Nanodiamond film with ‘ridge’ surface profile for chemical sensing

• Published in: Diamond and related materials 2008-04, Vol.17 (4), p.896-899
• Main Authors: Raina, Supil, Kang, W.P., Davidson, J.L.
• Format: Article
• Language: English
• Subjects: Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diffusion; interface formation; Electrochemical; Electrodes; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanodiamond; Physics; Plasma CVD; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Solid surfaces and solid-solid interfaces; Specific materials; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2007.12.027

A nanodiamond film with ‘ridge’ surface morphology was grown on highly doped n-type silicon substrate by microwave plasma enhanced chemical vapor deposition (MPECVD) using a H 2/CH 4/N 2 gas mixture. The nanodiamond electrode was electrochemically characterized by cyclic voltammetry using various concentrations of ferrocyanide in a background of 0.1 M KCl. The results show a wide working potential window of ~ 3 V, quasi-reversible kinetics with a high signal to noise S/B ratio. The peak current increases linearly with increasing concentration of ferrocyanide. Also, the peak current varies linearly with the square root of scan rate indicating planar diffusion dominated mass transport. The nanodiamond electrode exhibits excellent structure stability and electrochemical behavior without any surface pretreatment, indicating it is an excellent candidate for electrochemical sensing.