Water splitting carbon nanotubes

In many cases the potential application of single-walled carbon nanotubes is associated with solubility of this nanomaterial in different solvents. Unfortunately, nanotubes are poorly soluble in the most of organic solvents and are insoluble in water, and this fact especially hinders biological using SWNT. Weak solubility of SWNT is a result of substantial van der Waals attractions between nanotubes aggregated in bundles. To solve nanotubes in water without any covalent functionalization, a surfactant would be added into aqueous solution, and then this mixture is suspended by sonication. It is supposed that the sound wave splits bundles in aqueous solution. A surfactant in suspension adsorbed onto the nanotube surfaces precludes aggregation of nanotubes in bundles. 

This year, areas of analysis included (1) hydrogen production via natural gas splitting with a solar reactor, (2) biological water gas shift for hydrogen production from synthesis gas, and (3) assessment of the mass production of carbon nanotubes for hydrogen storage. 

Park JH, Kim S, Bard AJ (2006) Novel carbon-doped Ti02 nanotube arrays with high aspect ratios for efficient water splitting. Nano Lett 6 24—28... 

Keywords Artificial photosynthesis Carbon nanotubes Oxidation catalysis Oxygenic metal oxides Photo-induced electron transfer Polyoxometalates Water splitting... 

Carbon Nanotubes Potential in Water Splitting Catalysis. 136... 

A newly-designed photoelectrocatalytic (PEC) reactor for CO2 reduction, which combines photocatalysis by Ti02 and electrocatalysis by carbon nanotubes (CNT), has recently been proposed (Fig. 7) [152]. A proton-conductive Nafion membrane connects the Ti02 and CNT. Irradiation of the combined system of nano-structured Ti02 deposited on a metal Ti electrode with Pt modified CNT deposited on carbon sheet caused water splitting to H2 and O2. A half-cell for the cathodic electrode, i.e., Pt or Fe modified CNT electrode, produces various organic molecules such as 2-propanol due to electrocatalytic reduction of CO2 on the electrode. The proposed PEC reactor is incomplete in its present state. However, these systems are expected to couple water splitting and CO2 reduction, and thus it may establish a new artificial photosynthetic system. 

Fig. 8 Schematic representation of the complete electrochemical cell for water splitting where Ru4SiWio is anchored onto dendron-functionalized, positively charged, multi-wall carbon nanotubes.

Murphy, A.B. Does carbon doping of Ti02 allow water splitting in visible light Comments on Nanotube enhanced photoresponse of carbon modified (CM)-n-Ti02 for efficient water splitting . Sol. Energy Mat. Sol. C 92 3 (2008), pp. 363-367. 

Amade, R. Jover, E. Caglar, B. Mutlu, T. Bertran, E. (2011). Optimization of Mn02/Vertically Aligned Carbon Nanotube Composite for Sup>ercap)acitor Application. /. Power Sources, Vol. 196, pp. 5779-5783 Artero, V. Chavarot-Kerlidou, M. Fontecave, M. (2011). Splitting Water with Cobalt. Angew. Chem. Int Ed., Vol. 50, pp. 7238-7266... 

Slavcheva, E. Radev, I. Bliznakov, S. Topalov, G. Andreev, P. Budevski, E. (2007). Sputtered Iridium Oxide Films as Electrocatalysts for Water Splitting via PEM Electrolysis. Electrochim. Acta, Vol. 52, pp. 3889-3894 Soin, N. Roy, S.S. Karlsson, L. McLaughlin, J.A. (2010). Sputter Deposition of Highly Dispersed Platinum Nanoparticles on Carbon Nanotube Arrays for Fuel Cell Electrode Material. Diam. Relat. Mater., Vol. 19, pp. 595-598 Sundmacher, K. (2010). Fuel Cell Engineering Toward the Design of Efficient Electrochemical Power Plants. Ind, Eng. Chem, Res, Vol. 49, pp. 10159-10182... 

---