TY - CHAP

T1 - The oscillatory electro-oxidation of small organic molecules

AU - Varela, Hamilton

AU - Aragon Zulke, Alana Aragon

AU - Delmonde, Marcelo V.F.

PY - 2017/5/12

Y1 - 2017/5/12

N2 - The electrooxidation of small organic molecules such as formaldehyde, formic acid, methanol, ethanol, ethylene glycol, glycerol, and so on is relevant to interconversion between chemical and electrical energies. Although these have considerably low thermodynamic potentials compared to hydrogen, the oxidation process generally demands high overpotentials because of the ubiquitous formation of surface‐blocking carbonaceous species. The occurrence of parallel pathways and the formation of stable soluble by‐products also contribute to the poor utilization of all electrons involved in the oxidation process. Thecomplex kinetics found in these systems can also result in nonlinear manifestations such as autocatalysis and oscillatory dynamics. Besides the considerable amount of earlier experimental reports, only recently has some understanding of the chemistry underlying the dynamics been achieved. Moreover, a number of interesting and unexpected behaviors have been observed under oscillatory regime. In this chapter, we briefly review the recent advances on the oscillatory electrooxidation of small organic molecules, with emphasis on (a) the general phenomenology, (b) the use ofin situ andonline approaches, (c) the effect of temperature, and (d) the oscillations on modified surfaces. Moreover, some implications of nonlinearities in low temperature fuel cells are also discussed.

AB - The electrooxidation of small organic molecules such as formaldehyde, formic acid, methanol, ethanol, ethylene glycol, glycerol, and so on is relevant to interconversion between chemical and electrical energies. Although these have considerably low thermodynamic potentials compared to hydrogen, the oxidation process generally demands high overpotentials because of the ubiquitous formation of surface‐blocking carbonaceous species. The occurrence of parallel pathways and the formation of stable soluble by‐products also contribute to the poor utilization of all electrons involved in the oxidation process. Thecomplex kinetics found in these systems can also result in nonlinear manifestations such as autocatalysis and oscillatory dynamics. Besides the considerable amount of earlier experimental reports, only recently has some understanding of the chemistry underlying the dynamics been achieved. Moreover, a number of interesting and unexpected behaviors have been observed under oscillatory regime. In this chapter, we briefly review the recent advances on the oscillatory electrooxidation of small organic molecules, with emphasis on (a) the general phenomenology, (b) the use ofin situ andonline approaches, (c) the effect of temperature, and (d) the oscillations on modified surfaces. Moreover, some implications of nonlinearities in low temperature fuel cells are also discussed.

U2 - 10.1002/9783527803873

DO - 10.1002/9783527803873

M3 - Chapter

SN - 9783527341320

SP - 145

EP - 163

BT - Electrocatalysts for Low Temperature Fuel Cells

A2 - Maiyalagan, Thandavarayan Maiyalagan

A2 - Saji, Viswanathan S

PB - Wiley

ER -