“Functionalization and Chemical
                  Properties of Graphene”
  
Ø ♦ Speaker :카지노 토토Prof. Sunmin Ryu [Kyung Hee University]  
Ø ♦ Place : Physics Seminar Room (Science Bldg, 3-201)
Ø ♦ Date & Time : Nov, 25(Wed)카지노 토토3:00카지노 토토~카지노 토토4:00 pm

Abstract
  
Atom-thick graphene membrane holds substantial potential for applications in future molecular-scale
integrated electronics, transparent카지노 토토conducting카지노 토토membranes,카지노 토토nanocomposites,카지노 토토etc.카지노 토토To카지노 토토realize카지노 토토this
potential, chemical properties of graphene need to be understood and카지노 토토functionalization카지노 토토toolkits카지노 토토are
also required. To meet this need,카지노 토토surface카지노 토토chemistry카지노 토토of카지노 토토graphene카지노 토토has카지노 토토been카지노 토토explored카지노 토토by카지노 토토Raman
spectroscopy, AFM and STM scanning probes. In the first part of the talk, two chemical reactions of
graphene will be presented.카지노 토토Hydrogenation,카지노 토토the카지노 토토simplest카지노 토토basal카지노 토토plane카지노 토토functionalization,카지노 토토is카지노 토토highly
reversible and strongly dependent on the thickness of graphene in the rate. Graphene sheets can be
locally hydrogenated with a high spatial resolution. Thermal oxidation also proceeds at a higher카지노 토토rate
for single layer than double layer카지노 토토graphene and triple layer graphene behaves like bulk graphite. The
second part of the talk will illustrate the influence of underlying silicon dioxide substrates and ambient
gases on properties of graphene. Raman spectroscopy shows that freestanding graphene is essentially
charge-neutral implying that the “usual” hole-doping카지노 토토in카지노 토토supported카지노 토토graphene카지노 토토is카지노 토토mediated by oxide
substrates. An STM study카지노 토토reveals카지노 토토that카지노 토토thermal카지노 토토annealing카지노 토토generates카지노 토토out-of-plane카지노 토토deformation카지노 토토of
nanometer-scale wavelength and distortion in sp2 bonding on an atomic scale. Graphene카지노 토토deformed
by annealing is found to be chemically active enough to카지노 토토bind카지노 토토molecular oxygen,카지노 토토which카지노 토토leads t o카지노 토토a
strong hole-doping. A possible form of oxides will be discussed.
  
  
          Contact Person : Prof. Nam Ki Lee (054-279-2097, nklee@postech.ac.kr)