A Mechanism of Adsorption of beta-Nicotinamide Adenine Dinucleotide on Graphene Sheets: Experiment and Theory

作者：Pumera Martin^*; Scipioni Roberto; Iwai Hideo; Ohno Takahisa; Miyahara Yuji; Boero Mauro

来源：Chemistry - A European Journal, 2009, 15(41): 10851-10856.

DOI：10.1002/chem.200900399

• adsorption
• biosensors
• electrochemistry
• graphite
• molecular dynamics

beta-Nicotinamide adenine dinucleotide (NAD( )) and its reduced form (NADH) play major roles in the development of electrochemical enzyme biosensors; and biofuel cells. Unfortunately, the oxidation of NADH at carbon electrodes suffers from passivation of the electrodes and a decrease in passing currents. Here, we investigate experimentally and theoretically the reasons for such passivation. High-resolution X-ray photoelectron spectroscopy (HR-XPS), voltammetry, and amperometry show that adsorption occurs on the edges and "edge-like" defects of graphene sheets. HR-XPS and ab initio molecular dynamics show that the adsorption of NAD( ) molecules on the edges of graphene happens due to interaction with oxygen-containing groups such as carboxylic groups, while graphene edges substituted only with hydrogen are prone to passivation.

• 出版日期2009