Chemical Functionalization of BDD Electrodes

Most of the articles highlighted in Table 5.4 deal with 2D surfaces. In complementary work, Nebel and colleagues evaporated Ni NPs onto a BDD electrode and used the Ni as an etch mask to produce a BDD nanowrre electrode terminated with Ni NPs. This 3D electrochemical platform has been utilized for the electrochemical detection of glucose [158], immobilization of histidinylated biomolecules [159], and the immunosensing of immunoglobulin G [160]. 

As an alternative to metal NP deposition, where the stability of the metal NPs on the BDD has been in some cases questioned, ion implantation (II) was proposed by Einaga and colleagues as an alternative methodology. II modifies the near-surface structure of the BDD by heavy-ion bombardment and has been used to implant a range of different metal ions in the surface of BDD, including Ir [161], NP [162, 

During ion implantation, some of the sp bonds are broken and thus an aimeal-ing step is advocated to restore the surface, providing the critical damage level has not been exceeded. Annealing in a hydrogen atmosphere or plasma is also thought to be necessary to bring the metal to the surface. Nanoscopic holes, up to 200 nm, are also observed on the surface post treatment. The presence of the metal is confirmed by XPS. 

For halogenation with, for example, fluorine [169, 170] and chlorine [170], it is first necessary to activate the halogen gas to form free radicals this is typically achieved using high temperature, UHV conditions. A milder approach 

---