Formulation of chemically reduced graphene oxide assembly with poly(4‐vinyl pyridine) through noncovalent interaction

Abstract

Soluble chemically reduced graphene oxide (RGO)/poly(4-vinyl pyridine) (P4VP) assembly was attempted by totally noncovalent approach. Chemical reduction of P4VP/GO mixture by hydrazine produced soluble RGO/P4VP assembly with long term stability. Prepared RGO/P4VP assembly showed pH-dependent variation of optical transmittance. Transmittance of RGO/P4VP assembly solution at pH 2.0 dramatically increased more than 200% of transmittance of assembly at pH 6. This optical transmittance change was fully reversible. The detailed morphological features of assemble was evaluated by dynamic light scattering (DLS) and atomic force microscopy (AFM). It is estimated that RGO/P4VP assemblies were well separated each other at pH 6, enabling much higher optical absorption of RGO plates. At pH 2, protonation of pyridine ring occurs and this might hamper effective noncovalent interaction between RGO plate and protonated P4VP chains, forming bigger aggregates having less chance for optical absorption. This pHdependent optical modulation of RGO/P4VP assembly can be useful for the designing of pH-sensor, removable nanocatalyst, and targeted drug delivery, etc.

Production of graphene oxide from pitch-based carbon fiber

“…The compositional and structural similarities between p-GO and GO prompt us to investigate the formulation of soluble chemically reduced p-GO (p-rGO) through noncovalent interaction with aliphatic polymer having aqueous solubility 14 15 16 . To accomplish this, aqueous p-GO solution was mixed with aqueous P4VP solution with weight ratio of 1:10 (p-GO:P4VP), forming p-GO/P4VP mixture solution 17 . Addition of excess hydrazine and subsequent heating at 80 °C for 24 hrs produced soluble p-rGO/P4VP assembly solution with dispersion stability more than 6 months.…”

Simple noncovalent hybridization of polyaniline with graphene and its application for pseudocapacitor

“…Noncovalent approaches can overcome above limitation because no covalent linkage between organic molecules and graphene is required [22][23][24]. Until now, various p-conjugated small molecules such as pyrene and anthracene derivatives, and p-rich polymers such as poly(phenylene acetylene) have been reported to spontaneously bind on rGO through p-p interaction between them in the aqueous media [25][26][27].…”

Direct noncovalent conjugation of folic acid on reduced graphene oxide as anticancer drug carrier

“…Recently, several experimental studies have revealed that several aliphatic polymers such as polyacrylic acid, poly(N-isopropyl acrylamide) [21], polyacrylamide [22], poly(N-vinyl pyrrolidone) [23], poly(4-vinyl pyridine) [24], polyethylene glycol [25], Pluronic [26,27], aliphatic dendrimer [28],…”