MODIFIED METHOD BOEHM FOR DETERMINATION OF HYDROXY GROUPS IN CARBON NANOTUBES
https://doi.org/10.18384/2224-0209-2012-1-627
Abstract
In this paper we propose a modified version of Boehm's titration method of determination of hydroxyl groups contained in nanotubes in the form of phenolic group analogues in carboxyl groups, as well as in hydroxyl groups formed as a result of the hydrolysis of lactone and anhydride cycles. The proposed method is different from the known techniques, where decontamination is carried out by a long pass of inert gases (N2, Ar), by its way of removing CO2 from the reaction system in vacuum and applying conductometric method for determining the equivalence point, which allows to obtain more reproducible results with low amounts of functional groups (n 10-4 mol / g) in samples of carbon nanotubes.
References
1. Boehm H.P. Chemical identification of surface groups // Advances in catalysis and related subjects. 1966. №16 - Pp. 197-274.
2. Boehm H.P. Surface oxides on carbon and their analysis: a critical assessment // Carbon V. 40 (2002), pp. 145-149.
3. Goertzen S.L., Theriault K.D., Oickle A.M. e.a. Standardization of the Boehm titration. Part I. CO2 expulsion and endpoint determination // Carbon V. 48 (2010). - Pp. 1252-1261.
4. Oickle A.M., Goertzen S.L., Hopper K. R. Standardization of the Boehm titration: Part II. Method of agitation, effect of filtering and dilute titrant // Carbon V. 48 (2010). - Pp. 3313-3322.
5. Wang Z., Shirley M.D., Meikle S. T. e.a. The surface acidity of acid oxidised multi-walled carbon nanotubes and the influence of in-situ generated fulvic acids on their stability in aqueous dispersions // Carbon - 2009. V. 47. - P. 73 - 79.
Review
Views:
366
Email this article 