Development of nano boron-doped diamond electrodes for environmental applications

Boron doped diamond (BDD) is an outstanding electrode material with unique electrocatalytic properties and excellent stability, relevant to electrochemical advanced oxidation processes and electroanalytical techniques. From an environmental sustainability viewpoint, BDD electrodes are comprised only of earth abundant elements (carbon, boron, oxygen). However, a major drawback is the high manufacturing costs per unit surface area for BDD electrodes when fabricated using chemical vapor deposition or comparable surface deposition processes. BDD nanoparticles can provide an alternative manufacturing process that reduces costs by over 1000-fold while also improving catalytic activity. Herein, we demonstrate that nano-BDD electrodes can be fabricated by depositing BDD nanoparticles on a silicon substrate using a Nafion® ink-casting method. Scanning electron microscopy (SEM), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR) were used to investigate the electrode structural and morphological properties, which were compared to BDD electrodes manufactured using standard methods. Cyclic voltammetry measurements revealed similar electrochemical properties for both electrodes, with a broad “electrochemical window”, essential for effective production of ∙OH radicals without oxygen generation, providing an energy-efficient approach to degradation of pollutants in water. The electrocatalytic properties of the nano-BDD enabled electrodes were investigated using a [Fe(CN)₆]^3-/4- redox probe. The sensing properties of as-prepared nano-BDD electrodes was studied using Dopamine.