Cu2O Photocathode-Based PEC-PV Tandem Delivering 4.55% Solar-To-Hydrogen Efficiency (image) Ecole Polytechnique Fédérale de Lausanne Share Print E-Mail Caption Cu2O photocathode-based PEC-PV tandem delivering 4.55% solar-to-hydrogen efficiency. Credit P. Linfeng/EPFL Usage Restrictions Media purposes only. Commercial usage restricted; by permission only. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.