Photocatalytic H2 evolution rates over various CdSe samples: (a)
CdSe-120, (b) CdSe-140, (c) CdSe-160, (d) CdSe-180, (e) commercial
CdSe powder, (f) urchin-like CdSe and (g) CdSe QDs. No H2 could be
detected in the Na2SO3 and Na2S solution in the absence of CdSe catalysts