Graphene/Nano-Porous Silicon and Graphene/Bimetallic Silicon Nanostructures (Pt-M, M: Pd, Ru, Rh), Efficient Electrocatalysts for Hydrogen Evolution Reaction, Ali A. Ensafi, Mehdi Jafari-Asl, B. Rezaei,Phys Chem Chem Phys., 2015, 17, 23770–23782.

In  this  work  nano-porous  silicon  flour  (Nano-PSiF)  was  synthesized  first  and  then  there  was  an
investigation into its electrocatalytic activity for the electrochemical hydrogen evolution reaction (HER).
The results showed that Nano-PSiF has good electrocatalytic activity for the HER when compared with
PSiF. In the second section, Pt and Pt–M (M = Pd, Rh, Ru) bimetallic silicon nanostructures were prepared
by a direct reduction of the metal (Pt, Pt–Pd, Pt–Rh and Pt–Ru) on the surface of the PSiF by a galvanic
exchange  mechanism.  The  electrocatalytic  activity  of  the  bimetallic  silicon  nanostructures  (Pt–M/PSiF)
were evaluated for the HER. The results showed that all of the Pt–M/PSiFs have excellent electrocatalytic
activity  for  the  HER  in  a  0.5  mol  L1 H 2 SO 4 solution.  For  the  Pt/PSiF,  the  Tafel  slope  of  Pt/PSiF  was
46.9  mV  dec1 ,  indicating  its  excellent  electrocatalytic  activity  for  the  HER  and  it  is  comparable  with
commercial Pt/C. On the other hand, the bimetallic silicon nanostructures showed better electrocatalytic
activity than Pt/PSiF for the HER (lower Tafel slope, and higher a). Finally, exfoliated graphene oxide was
electro-deposited on the surface of a glassy carbon electrode (eRGO/GCE) and used as a sub-layer for
the Pt–M/PSiF. Then, the electrocatalytic activities of the bimetallic silicon nanostructures on the eRGO/
GCE were investigated for the HER. The results showed that there was a higher electrocatalytic activity for
Pt–M/PSiF–eRGO/GCE when compared with Pt–M/PSiF–GCE.