The results of nanoparticle size and curvature being influential upon neuronal adhesion has great implications towards biomaterial design, and the ability to pattern neurons using nanodiamond tracks shows great promise for applications both in vitro and in vivo.

Graphene on hydrogen terminated monolayer nanodiamond heterostructures provides a new way to improve carrier transport characteristics of the graphene, offering up to 60% improvement when compared with similar graphene on SiO2/Si substrates. These heterostructures offers excellent current-carrying abilities whilst offering the prospect of a fast, low cost and easy methodology for device applications. The use of ND monolayers is also a compatible technology for the support of large area graphene films. The nature of the C-H bonds between graphene and H-terminated NDs strongly influences the electronic character of the heterostructure, creating effective charge redistribution within the system. Field effect transistors (FETs) have been fabricated based on this novel herterostructure to demonstrate device characteristics and the potential of this approach.

The expansion of diamond-based electronics in the area of biological interfacing has not been as thoroughly explored as applications in electrochemical sensing. However, the biocompatibility of diamond, large safe electrochemical window, stability, and tunable electronic properties provide opportunities to develop new devices for interfacing with electrogenic cells. Here, the fabrication of microelectrode arrays (MEAs) with boron-doped nanocrystalline diamond (BNCD) electrodes and their interfacing with cardiomyocyte-like HL-1 cells to detect cardiac action potentials are presented. A nonreductive means of structuring doped and undoped diamond on the same substrate is shown. The resulting BNCD electrodes show high stability under mechanical stress generated by the cells. It is shown that by fabricating the entire surface of the MEA with NCD, in patterns of conductive doped, and isolating undoped regions, signal detection may be improved up to four-fold over BNCD electrodes passivated with traditional isolators.

The electrical properties of monodispersed detonation nanodiamonds (DNDs) have been studied; a resistivity of the order of 1012 Ω/sq has been determined, with only one significant conduction pathway being observed. The dielectric character of the DND particles is also good, with dielectric loss tangent values in the range 0.05–0.5 being recorded. These combined observations suggest DNDs behave in electrical terms similar to thin film diamond, and that electrical applications for DNDs are worthy of pursuit. Since a simple room temperature sonication process has been used for their deposition, coating a wide-range of three-dimensional substrate materials will be possible. A limitation on the electrical use the monodispersed DNDs, at least in the untreated, as-deposited from solution form used here, is the catastrophic loss of diamond-like character at temperatures above 400 °C.

Undergraduate analytical chemistry courses emphasize fundamental stoichiometric and physicochemical analytical techniques with statistical analysis and linear calibrations. Higher-level data analysis techniques may not be included in the college junior-level curriculum, but widely available software enables more complex analysis to be accessible. In this work, activities to train students in multicomponent spectral curve fitting (using Microsoft Excel’s Solver) and utilizing matrix algebra were incorporated within a large-enrollment undergraduate analytical chemistry lecture setting. When analyzing multiple compounds in solutions without separation pretreatment, both curve-fitting and classical matrix approaches are valuable techniques for students to understand and execute using commercially available software. When hands-on activities, multimedia screencasts, and in-class data collection and analysis were implemented, students were trained to employ these advanced analysis methods. The efficacy of the in-class practical activities was assessed with pre- and post-test instruments that quantified gains in learning outcomes. Inclusion of such activities will empower students with an expanded repertoire of these important analytical methods and their applications with a real world, portable, active-learning approach that can be completed in a lecture setting with nonhazardous samples.

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Impedance spectroscopy has been used to investigate conductivity within boron-doped diamond in an intrinsic/delta-doped/intrinsic (i-δ-i) multilayer structure. For a 5 nm thick delta layer, three conduction pathways are observed, which can be assigned to transport within the delta layer and to two differing conduction paths in the i-layers adjoining the delta layer. For transport in the i-layers, thermal trapping/detrapping processes can be observed, and only at the highest temperature investigated (673 K) can transport due to a single conduction process be seen. Impedance spectroscopy is an ideal nondestructive tool for investigating the electrical characteristics of complex diamond structures.

Impedance spectroscopy has been used to investigate the conductivity displayed by diamond doped with boron in an intrinsic-δ-layer-intrinsic multilayer system with differing δ-layer thicknesses. Carrier transport within 5 nm δ-layer structures is complex, being dominated by conduction in the interfacial regions between the δ-layer and the intrinsic regions, as well as conduction within the δ-layer itself. In the case of 3.2 nm thick δ-layers the situation appears improved with uncapped samples supporting only two conduction paths, one of which may be associated with transport outside of the δ-layer, the other low transport within the δ-layer complex diamond structures. Introduction of the capping layer creates a third conduction path associated with unwanted boron in the capping layer-δ-layer interface.