Photolyse de l'eau au moyen de l'énergie solaire

• Research unit: SFOE
• Project number: 101747

Key words (German)

TP0066;F - Wasserstoff

Short description (German)

Photolyse de l'eau au moyen de l'énergie solaire

Publications / Results (English)

We pursued studies of solar-light-driven photo-electrolysis cell employing semi-transparent WO3 photoanode. The stability of the photoanode in different electrolytes has been evaluated. Long term photo-electrolysis runs allowed us to identify solutions of sodium chloride as being the optimum electrolytes for water cleavage in hydrogen and oxygen, with some amount of chlorine formed as a by-product. In particular, the photo-electrolysis of a 0.5 M solution of sodium chloride, which is a composition close to sea water, results in the formation of ca 20% of chlorine at the WO3 photoanode with oxygen remaining the main product. Thus, the sea water appears as an abundant, non-toxic electrolyte suitable for massive hydrogen production via photo-electrolysis. Charge and mass transport are among the main factors determining the efficiency of nanostructured semiconducting photo-electrodes. In contrast with the prevailing current opinion, our results show that it is the migrational/diffusional transport within electrolyte filling the pores of the photo-electrode and not the electron diffusion across the semiconductor matrix which controls the photocurrent-voltage behaviour. Apparently, the only restrictions to the use of relatively thick nanostructured electrodes are the penetration depth of the incident light, the rate of diffusion/migration of the electroactive species within the electrode and the conductivity of the electrolyte.

Auftragnehmer/Contractant/Contraente/Contractor:
Université de Genève

Autorschaft/Auteurs/Autori/Authors:
Augustynski,Jan
Jorand Sartoretti,C.
Bilecka,I.
Solarska,R.

Publications / Results (French)

Related documents

• Photolyse de l’eau et production d’hydrogène et d’oxygène au moyen de l’énergie solaire | Projektteil Universität Genf - Rapport annuel 2006 [PDF] 305 kB