2011/05/04 by Wangyang Fu, Cornelia Nef, Oren Knopfmacher +4
Chemical Engineering · Materials Science · Physics and Astronomy · #Analytical Chemistry and Sensors #Aqueous solution #Electrode #Fluorobenzene #Graphene #Graphene research and applications #Layer (electronics) #Supercapacitor Materials and Fabrication #Transistor #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1021/nl201332c
arxiv created 2011/05/04 · openalex publication_date 2011/07/18 · arxiv updated 2015/05/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We observe very small gate-voltage shifts in the transfer characteristic of as-prepared graphene field-effect transistors (GFETs) when the pH of the buffer is changed. This observation is in strong contrast to Si-based ion-sensitive FETs. The low gate-shift of a GFET can be further reduced if the graphene surface is covered with a hydrophobic fluorobenzene layer. If a thin Al-oxide layer is applied instead, the opposite happens. This suggests that clean graphene does not sense the chemical potential of protons. A GFET can therefore be used as a reference electrode in an aqueous electrolyte. Our finding sheds light on the large variety of pH-induced gate shifts that have been published for GFETs in the recent literature.