Boron in electrode materials

Boron as a dopant allows silicon and carbon materials to significantly change their conductivity and thereby open up applications in particular with boron-doped diamond (sp -carbon) as mechanically and chemically robust electrode material. The range of beneficial effects of boron in boron-doped diamond as electrode materiaP has been reported. Bio-electrochemical processes like the oxidation of NADH are possible with diamond dominating the interfacial chemistry. The sp nature of the diamond allows adsorption processes to be modified, and electrode erosion to be minimised, with electroanalytical application even under extreme conditions, for example in the presence of ultrasound and for pharmaceutical components. Boron surface functional groups have been reported to be crucial for electron transfer, for example, during glucose oxidation.  

In addition to direct immobilisation of boronic acids onto electrode surfaces, it is possible to dissolve the boronic acid receptor into non ater-miscible organic liquids such as 4-(3-phenylpropyl)pyridine for two-phase immobilisation onto the electrode surface. The resulting liquidjliquid redox system allows target anions (phosphate, carbonate, a-hydroxy carbojq lates ) to be extracted from the water phase into the organic phase driven by the eomplex formation with the boronic acid. In this way many interfering processes ean be suppressed and the selective binding of the boronic acid exploited. 

Pyrene boronic acid derivatives that associate with graphitic electrode surfaces (A) or carbon nanoparticles (B) to give caffeic acid sensitive surfaces. (Reproduced from ref. 54 with permission from The Royal Society 

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