Abstract:
A method of fabricating a plurality of single crystal CVD diamonds. The method includes mounting a plurality of single crystal diamond substrates on a first carrier substrate. The plurality of single crystal diamond substrates is subjected to a first CVD diamond growth process to form a plurality of single crystal CVD diamonds on the plurality of single crystal diamond substrates. The plurality of single crystal CVD diamonds are mounted in a recessed carrier substrate and subjected to a second CVD diamond growth process.
Abstract:
An electrode comprising synthetic high-pressure high-temperature diamond material, the diamond material comprising a substitutional boron concentration of between 1×1020 and 5×1021 atoms/cm3 and a nitrogen concentration of no more than 1019 atoms/cm3. The electrode has a ΔE3/4-1/4 as measured with respect to a saturated calomel reference electrode in an aqueous solution containing 0.1 M KNO3 and 1 mM of Ru(NH3)63+ selected any of less than 70 mV, less than 68 mV, less than 66 mV, and less than 64 mV, and/or a peak to peak separation ΔEp as measured with respect to a saturated calomel reference electrode in an aqueous solution containing 0.1 M KNO3 and 1 mM of Ru(NH3)63+ selected any of less than 70 mV, less than 68 mV, less than 66 mV, and less than 64 mV.
Abstract:
An electrochemical cell for treating a fluid, the electrochemical cell comprising: at least two opposing electrodes defining a flow path for the fluid between the electrodes, where at least one of the electrodes is formed of electrically conductive diamond material; drive circuitry configured to apply a potential across the electrodes such that a current flows between the electrodes when the fluid is flowed through the flow path between the electrodes; and a housing in which the electrodes are disposed, the housing comprising pressure seals configured to containing the fluid within the fluid path and a support structure for supporting the electrodes, wherein the support structure and the pressure seals are configured such that the electrochemical cell has an operating pressure in a range 2 to 10 bar within which the electrodes are supported without fracturing and within which the fluid is contained within the flow path, wherein the electrodes are spaced apart by a distance in a range 0.5 mm to 4 mm, and wherein the drive circuitry is configured to apply a potential across the electrodes giving a current density ≥15,000 Amp/m2 over an electrode area of at least 20 cm2 for an operating voltage of no more than 20 V.
Abstract:
An electrochemical sensor apparatus and electrochemical sensing method are described, using one or more working electrodes (110) of boron doped diamond (BDD). A cathodic reduction process provides a cathodic measurement and, substantially simultaneously, an anodic oxidation process provides an anodic measurement. A sum of a content of two equilibrium species within an aqueous system is obtained using both the cathodic measurement and the anodic measurement. One example measures total free chlorine by simultaneously measuring hypochlorous acid (HOCl) and hypochlorite ion (OCl-). The BDD working electrode (110) comprises at least one ablated region (115) which introduces non-diamond carbon sp2 material. The ablated region (115) may comprise one or more grooves (114) which are cut into the working surface (112), e.g. by a laser.