Pd/Ag nanosheet as a plasmonic sensing platform for sensitive assessment of hydrogen evolution reaction in colloid solutions

A nanoplasmonic hydrogen-sensing system based on palladium/silver nanosheets (Pd/Ag NSs) was developed and used for sensitive assessment of the hydrogen evolution reaction (HER) in colloid solutions. As a model HER system, the semiconductor CdS/CdSe core/shell quantum dot (QD)-based hydrogen-producing colloidal system was used, and the HER performances of QDs with two different surface coatings were assessed in this study. In the sensing system, the photocatalytically generated hydrogen reacts with Pd/Ag NSs, resulting in a gradual red-shift of localized surface plasmon resonance, which to a certain degree is almost linearly proportional to the amount of hydrogen generated. Such a nanoplasmonic hydrogen sensing platform would be useful as an alternative for optical assessment and fast selection of a highly efficient and cost-effective solar hydrogen generation system for practical applications.