Microwave-assisted polyol method

A popular method for the synthesis of metal nanowires is the use of the polyol process,lal wherein the metal salt Is reduced in the presence of PVP to yield nanowires of the desired metal. For example, Ag nanowires have been rapidly synthesized using a microwave-assisted polyol method.161 CoNi nanowires are obtained by heterogeneous nucleation in liquid polyol.162 While Bi nanowires have been prepared employing NaBiO, as the bismuth source.161 Pd nanobars are synthesized by varying the type and concentration of reducing agent as well as reaction temperature.1 ... 

Nekooi P, Akbari M, Amini MK (2010) CoSe nanoparticles prepared by the microwave-assisted polyol method as an alcohol and fmmic acid tolerant oxygen reduction catalyst. Int J Hydrogen Energy 35(12) 6392-6398... 

Figure 4.10. DMFC polarization curves using PtSn anode catalysts produced by a microwave-assisted polyol method. Anode catalyst load 4 mg cm , 2 M CH3OH with 2 ml min cathode Pt/C 3 mg cm , O2 pressure not specified in the original source, O2 flow rate 500 cm min 353 K [85]. (Reproduced from Electrochemistry Communications, 8(1), Liu Z, Guo B, Hong L, Lim TH, Microwave heated polyol synthesis of carbon-supported PtSn nanoparticles for methanol electrooxidation, 83-90, 2006, with permission from Elsevier.)...

The superior aetivity of Pd/C compared to Pt/C, both produced by the microwave assisted polyol method, was also demonstrated in direct formic acid fuel cells [173]. With Pd/C as the anode catalyst the maximum power output at 298 K was 120 mW cm" while Pt/C yielded only 65 mW cm . The catalyst load was 8 mg cm in both cases and the formic acid concentration in the fuel cell 3 M. 

Figure 9.9. (a) j(E) polarization curves at different electrode rotation rates (S2) recorded on Pt(40wt%)/C catalyst prepared via a microwave-assisted polyol synthesis method in a 02-saturated 0.5M H2SO4 electrolyte. (T = 20°C, scan rate = 1 mVs ) (b) Koutecky-Levich plots determined from (a) at different potentials. 

Na2Si03, Na4Si20s, gas phase reduction [11,15,19,21]. Generally, metal chloride salts (H2PtCl6, RuCls, NiCU, etc.) are used as metal precursors. As metal chloride salts may reduce the dispersion of nanoparticles (NPs) on support materials [21], a number of binary and ternary electrocatalysts have also been prepared by using chloride-free precursor salts such as carbonyl, nitrate, sulfite complexes, etc. [15,21]. NaBH4 and polyol reduction methods are repeatedly used [15,21-25]. Recently, the microwave assisted chemical reduction method has also been used to obtain better dispersion and reduce the particle sizes of metal catalysts [24-26]. 

Tsuji, M., Nishizawa, Y, Matsumoto, K., Miyamae, N., Tsuji, T, and Zhang, X. (2007) Rapid synthesis of silver nanostructures by using microwave-polyol method with the assistance of Pt seeds and pols inylpyrrolidone. Colloid. Surf. A, 293(1-3), 185-194. 

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