Photocatalytic Hydrogen Generation by CdSe/CdS Nanoparticles

Abstract
The hydrogen (H2) production activity of various CdSe semiconductor nanoparticles, including CdSe and CdSe/CdS quantum dots (QDs), CdSe quantum rods (QRs), and CdSe/CdS dot-in-rods (DIRs), was compared in a photocatalytic system with a molecular Ni2+ catalyst. With equivalent photons absorbed, the H2 generation activity orders as: CdSe QDs >> CdSe QRs > CdSe/CdS QDs > CdSe/CdS DIRs, which is surprisingly the opposite of the electron-hole separation efficiency. Calculations of photoexcited surface charge densities are positively correlated with the H2 production rate and suggest the size of the nanoparticle plays a critical role in determining the relative efficiency of H2 production.
Funding Information
  • Basic Energy Sciences (DE-FG02-09ER16121)