Artificial leaf: New efficiency record for solar hydrogen production is 14 percent

17 year old record value finally exceeded

Date:

September 15, 2015

Source:

Helmholtz-Zentrum Berlin für Materialien und Energie

Summary:

An international team has succeeded in considerably increasing the efficiency for direct solar water splitting with a tandem solar cell whose surfaces have been selectively modified. The new record value is 14 percent and thus tops the previous record of 12.4 percent, broken now for the first time in 17 years.

Next goals visible

"Forecasts indicate that the generation of hydrogen from sunlight using high-efficiency semiconductors could be economically competitive to fossil energy sources at efficiency levels of 15 % or more. This corresponds to a hydrogen price of about four US dollars per kilogramme," says Prof. Thomas Hannappel, from the photovoltaics group at TU Ilmenau, who was academic advisor for the work. Prof. Hans-Joachim Lewerenz from the Joint Center for Artificial Photosynthesis at the California Institute of Technology, who worked closely with May, said:"We are nearly there. If we are successful now in reducing the charge carrier losses at the interfaces somewhat more, we might be able to chemically store more than even 17 % of the incident solar energy in the form of hydrogen using this semiconductor system."