Overcoming the Physical Limitation of Modern Photocatalytic Solar Water-Splitting Systems: Probable Solution with Plasmonic Metallic Nanoparticles Linked by MIM Junction

In this article, general operating principles for modern photocatalytic solar water-splitting systems are reviewed from a physics perspective, and their fundamental limitations are identified. Several potential approaches to overcome the identified limitations are proposed, and a new solar water-splitting system unifying those approaches based on plasmonic metal nanoparticles linked by a metal-insulator junction is described. Based on already existing scientific knowledge, some probable features of the proposed system are briefly discussed, and an initial theoretical analysis of electromagnetic wave-propagation modeling was performed with COMSOL Multiphysics software. In addition, some rectification capabilities for the metal insulator–metal junction embedded in the system are calculated using a simplified Simmons model for tunneling currents. A probable approach for initial system synthesis with existing nanotechnology techniques is proposed, and its limitations and probable bottlenecks are marked.