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Role of the Electron Spin Polarization in Water Splitting.

ABSTRACT: We show that in an electrochemical cell, in which the photoanode is coated with chiral molecules, the overpotential required for hydrogen production drops remarkably, as compared with cells containing achiral molecules. The hydrogen evolution efficiency is studied comparing seven different organic molecules, three chiral and four achiral. We propose that the spin specificity of electrons transferred through chiral molecules is the origin of a more efficient oxidation process in which oxygen is formed in its triplet ground state. The new observations are consistent with recent theoretical works pointing to the importance of spin alignment in the water-splitting process.

SUBMITTER: Mtangi W

PROVIDER: S-EPMC4685426 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Role of the Electron Spin Polarization in Water Splitting.

Mtangi Wilbert W Kiran Vankayala V Fontanesi Claudio C Naaman Ron R

The journal of physical chemistry letters 20151201 24

We show that in an electrochemical cell, in which the photoanode is coated with chiral molecules, the overpotential required for hydrogen production drops remarkably, as compared with cells containing achiral molecules. The hydrogen evolution efficiency is studied comparing seven different organic molecules, three chiral and four achiral. We propose that the spin specificity of electrons transferred through chiral molecules is the origin of a more efficient oxidation process in which oxygen is f ...[more]

PMID: 26615833

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