“…The potential of diamond as an electrochemical transducer has attracted remarkable interest due to its chemical stability, wide potential window, low background current and bio-compatibility [53,[84][85][86] of other commonly exploited materials such as silicon (Si) [87,88], silicon dioxide (SiO 2 ) [89,90], tin dioxide (SnO 2 ) [91,92], gold (Au) [93,94] and glassy carbon [95,96]. High-quality diamond films typically possess a potential window of ≥ 3.25 V, owing to the large over-potentials for both oxygen and hydrogen evolution [97,98] as a result of diamond to be either insulating, semiconducting or metallic, with its appearance moving from transparent to black (optical gap of 5.47 eV), as a result of diamonds ability to be either p-or n-type doped [97][98][99].…”