René Hoffmann

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In atomic force microscopy (AFM), sharp and wear-resistant tips are a critical issue. Regarding scanning electrochemical microscopy (SECM), electrodes are required to be mechanically and chemically stable. Diamond is the perfect candidate for both AFM probes as well as for electrode materials if doped, due to diamond's unrivaled mechanical, chemical, and(More)
Silicon carbide (SiC) films have been used frequently for high-frequency and powder devices but have seldom been applied as the electrode material. In this paper, we have investigated the electrochemical properties of the nanocrystalline 3C-SiC film in detail. A film with grain sizes of 5 to 20 nm shows a surface roughness of about 30 nm. The resistivity of(More)
Silicon carbide has been proved as a candidate for power and high-frequency devices. In this paper, we show the application of nanocrystalline 3C-SiC as an electrochemical electrode and its electrochemical functionalization for biosensing applications. SiC electrodes show a wider potential window and lower background current than glassy carbon electrodes.(More)
Nanocrystalline diamond nanoelectrode arrays (NEAs) have been applied to investigate surface-sensitive adsorption phenomena at the diamond-liquid interface. The adsorption of neutral methyl viologen (MV(0) ) was used as a model system. The adsorption of MV(0) was examined on hydrogen- and oxygen-terminated surfaces. On the hydrogenated nanoelectrode(More)
The crystalline form of sp(3)-hybridized carbon, diamond, offers various electrolyte-stable surface terminations. The H-termination-selective attachment of nitrophenyl diazonium, imaged by AFM, shows that electrochemical oxidation can control the fractional hydrogen/oxygen surface termination of diamond on the nanometer scale. This is of particular interest(More)
Integrated all-diamond ultramicroelectrode arrays (UMEAs) were fabricated using standard photolithography processes. The array consisted of typically 45 ultramicroelectrodes with a diameter of 10 μm and with a center-to-center spacing of 60 μm. The quasi-reference and counter electrodes were made from conductive diamond and were integrated on a 5 × 5 mm(2)(More)
Monosized (∼4 nm) diamond nanoparticles arranged on substrate surfaces are exciting candidates for single-photon sources and nucleation sites for ultrathin nanocrystalline diamond film growth. The most commonly used technique to obtain substrate-supported diamond nanoparticles is electrostatic self-assembly seeding using nanodiamond colloidal suspensions.(More)
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