Boron-doped diamond electrode: synthesis, characterization, functionalization and analytical applications

Abstract

In recent years, conductive diamond electrodes for electrochemical applications have been a major focus of research and development. The impetus behind such endeavors could be attributed to their wide potential window, low background current, chemical inertness, and mechanical durability. Several analytes can be oxidized by conducting diamond compared to other carbon-based materials before the breakdown of water in aqueous electrolytes. This is important for detecting and/or identifying species in solution since oxygen and hydrogen evolution do not interfere with the analysis. Thus, conductive diamond electrodes take electrochemical detection into new areas and extend their usefulness to analytes which are not feasible with conventional electrode materials. Different types of diamond electrodes, polycrystalline, microcrystalline, nanocrystalline and ultrananocrystalline, have been synthesized and characterized. Of particular interest is the synthesis of boron-doped diamond (BDD) films by chemical vapor deposition on various substrates. In the tetrahedral diamond lattice, each carbon atom is covalently bonded to its neighbors forming an extremely robust crystalline structure. Some carbon atoms in the lattice are substituted with boron to provide electrical conductivity. Modification strategies of doped diamond electrodes with metallic nanoparticles and/or electropolymerized films are of importance to impart novel characteristics or to improve the performance of diamond electrodes. Biofunctionalization of diamond films is also feasible to foster several useful bioanalytical applications. A plethora of opportunities for nanoscale analytical devices based on conducting diamond is anticipated in the very near future

Electrochemical oxidation of dihydronicotinamide adenine dinucleotide (NADH): comparison of highly oriented pyrolytic graphite (HOPG) and polycrystalline boron-doped diamond (pBDD) electrodes

“…5 × 10 20 atoms cm −3 , above the metallic threshold as confirmed by secondary ion mass spectrometry (SIMS). 53 The pBDD had a roughness of 1-2 nm within a facet and 1-5 nm between grains, flat on the scale of SECCM and voltammetric measurements. 51 Studies of basal plane HOPG employed one of three different grades: either ZYB or SPI-3 grade (SPI Supplies, West Chester, PA), or an ungraded HOPG sample of the highest quality, 30 originating from Dr. Arthur Moore at Union Carbide (now GE Advanced Ceramics), and kindly provided by Prof. R. L. McCreery of the University of Alberta, Canada, which we refer to throughout as "AM grade").…”

“…This strongly suggests that for graphite the electrochemical response is mainly determined by the basal surface, not the step edges. In the case of pBDD, [51][52][53] although recognized for combining high stability and resistance to chemical fouling, the repetitive cycling showed a decrease in current response over the 10 cycles, but not to the same extent as HOPG. …”

Nanocrystalline diamond microelectrode arrays fabricated on sapphire technology for high-time resolution of quantal catecholamine secretion from chromaffin cells

“…Stable covalent functionalisations and different terminations (H, NH, O, F) can be easily obtained on the NCD electrode surface. This, together with the optical transparency, make boron-doped NCD on sapphire a promising material to combine electrochemical and fluorescence detection for biosensing applications (Zhou and Zhi, 2009;Luong et al, 2009). Boron-doped diamond thin films deposited on a conical Pt wire have been already successfully used for low time resolution amperometric monitoring of NE release from sympathetic nerves innervating a large area of the mesenteric artery (Park et al, 2006).…”

Probing the nature of electron transfer in metalloproteins on graphene-family materials as nanobiocatalytic scaffold using electrochemistry

“…While usually redox centers of proteins are often buried within folded polypeptide shells, which are usually regarded as poor electron conductors, a number of metalloproteins have been found to undergo direct ET at various surfaces known since the seminal work of Hill and co-workers. 34 Earlier efforts were taken to find appropriate electrode surfaces include for example, edge-plane highly-oriented pyrolytic graphite; HOPG, 33 boron-doped diamond; BDD), 35 and tailored metal electrode surface with appropriate functional groups (gold modified with self-assembled monolayers). 36 More recently, electrode surfaces prepared from nanomaterials facilitated protein ET have attracted particular interest due to excellent electrical conductivity, tunable surface chemistry and morphology.…”