PMID- 26803603
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20160608
LR  - 20170731
IS  - 1095-7103 (Electronic)
IS  - 0021-9797 (Linking)
VI  - 467
DP  - 2016 Apr 1
TI  - pKa determination of graphene-like materials: Validating chemical 
      functionalization.
PG  - 239-244
LID - S0021-9797(16)30013-3 [pii]
LID - 10.1016/j.jcis.2016.01.013 [doi]
AB  - We report a novel pKa determination for different graphene-like samples: graphene 
      oxide (GO), reduced GO (rGO), graphene nanoribbons (GNR), oxidized GNR (GONR), 
      thiol- and imidazole-functionalized GO (GOSH and GOIMZ, respectively) and 
      thiol-functionalized GONR (GONRSH). Using the specialized computational program 
      BEST7 for treating titration curves, pKas for different functional groups were 
      discriminated (confirmed by infrared spectra) and their composition quantified. 
      Overall, three equilibria were distinguished, two relative to carboxylic acids 
      exhibiting different acidic degrees (pKa1 approximately 4.0 and pKa2 approximately 6.0) and one relative to 
      alcohols (pKa4 approximately 10.0). Upon functionalization on carboxylate sites, thiol 
      (pKa(GOSH/GONRSH)=6.7) and imidazole (pKa(GOIMZ)=6.6) moieties were discerned, 
      followed by a decrease of their carboxylate percentage (compared to the 
      precursors), thus allowing determining the degree of functionalization (48% and 
      36% of thiol content for GOSH and GONRSH respectively, and 29% of imidazole for 
      GOIMZ). The proposed method is innovative and simpler when compared to the 
      traditional tools usually employed to quantify chemical functionalization.
CI  - Copyright (c) 2016 Elsevier Inc. All rights reserved.
FAU - Orth, Elisa S
AU  - Orth ES
AD  - Department of Chemistry, Universidade Federal do Parana (UFPR), CP 19081, CEP 
      81531-990, Curitiba, PR, Brazil. Electronic address: elisaorth@ufpr.br.
FAU - Ferreira, Jose G L
AU  - Ferreira JGL
AD  - Department of Chemistry, Universidade Federal do Parana (UFPR), CP 19081, CEP 
      81531-990, Curitiba, PR, Brazil.
FAU - Fonsaca, Jessica E S
AU  - Fonsaca JES
AD  - Department of Chemistry, Universidade Federal do Parana (UFPR), CP 19081, CEP 
      81531-990, Curitiba, PR, Brazil.
FAU - Blaskievicz, Sirlon F
AU  - Blaskievicz SF
AD  - Department of Chemistry, Universidade Federal do Parana (UFPR), CP 19081, CEP 
      81531-990, Curitiba, PR, Brazil.
FAU - Domingues, Sergio H
AU  - Domingues SH
AD  - Graphene and Nano-materials Research Center - Mackgraphe - Graphene and 
      Nanomaterials Research Center, Mackenzie Presbyterian University, 01302-907 Sao 
      Paulo, Brazil.
FAU - Dasgupta, Archi
AU  - Dasgupta A
AD  - Department of Chemistry and Department of Materials Science and Engineering, The 
      Pennsylvania State University, University Park, PA 16802, USA.
FAU - Terrones, Mauricio
AU  - Terrones M
AD  - Department of Physics and Center for 2-Dimensional and Layered Materials, The 
      Pennsylvania State University, University Park, PA 16802, USA; Department of 
      Chemistry and Department of Materials Science and Engineering, The Pennsylvania 
      State University, University Park, PA 16802, USA.
FAU - Zarbin, Aldo J G
AU  - Zarbin AJG
AD  - Department of Chemistry, Universidade Federal do Parana (UFPR), CP 19081, CEP 
      81531-990, Curitiba, PR, Brazil.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20160109
PL  - United States
TA  - J Colloid Interface Sci
JT  - Journal of colloid and interface science
JID - 0043125
OTO - NOTNLM
OT  - Graphene functionalization
OT  - Graphene nanoribbon
OT  - Titration
OT  - pK(a) determination
EDAT- 2016/01/25 06:00
MHDA- 2016/01/25 06:01
CRDT- 2016/01/25 06:00
PHST- 2015/11/26 00:00 [received]
PHST- 2016/01/06 00:00 [revised]
PHST- 2016/01/08 00:00 [accepted]
PHST- 2016/01/25 06:00 [entrez]
PHST- 2016/01/25 06:00 [pubmed]
PHST- 2016/01/25 06:01 [medline]
AID - S0021-9797(16)30013-3 [pii]
AID - 10.1016/j.jcis.2016.01.013 [doi]
PST - ppublish
SO  - J Colloid Interface Sci. 2016 Apr 1;467:239-244. doi: 10.1016/j.jcis.2016.01.013. 
      Epub 2016 Jan 9.