Alfa Chemistry provides customers with non-covalent bond modification services on the graphene surface. The non-covalent bond surface modification of graphene is the use of hydrophobic adsorption, π-π or cation-π and hydrogen bonding to make some organics adhere to the graphene surface. In the practical application of functionalized graphene, it is usually necessary to improve the dispersion of graphene and maintain the inherent electrical conductivity and thermal conductivity of graphene.
Our modification capabilities include, but are not limited to, following:
- Hydrophobic Adsorption
Amphiphilic molecules are a class of organic substances with both hydrophobic and hydrophilic structures. By combining the hydrophobic segment with the graphene, the hydrophilic segment of the amphiphilic molecule can change the surface properties of the graphene and make it dispersed well in the aqueous solution. In addition, polar polymers can also improve the surface properties of graphene.
- π-π or Cation-π Interaction
Organic small molecules, polymers and biological macromolecules with conjugated structure can produce π-π stacking interactions with graphene, and then improve the surface activity of graphene through special functional groups, which gives it functionality to broaden the graphene application areas.
Figure 1. Schematic of the interactions of graphene with m-dinitrobenzene. (Chen X. X, et al. 2015)
In addition to π-π interactions, there are cation-π interactions between the cations of Ionic liquid (IL) and graphene, and anions can change the surface properties of graphene.
Figure 2. The PIL-modified graphene sheets (PIL-G). (Kim T. Y, et al. 2010)
- Hydrogen Bond
Some oxygen-containing groups remain on the surface of graphene prepared by redox method, and the polar functional groups in some organic structures can form hydrogen bonds with these oxygen-containing groups.
Properties and Applications
| Modified Group | Modification Agent | Interaction Type | Property | Application |
| Carbon six-membered | Sulfonated styreneethylene/butylene–styrene copolymer | Copolymerization | Conductive | Nanocomposites |
| Carbon six-membered ring | Tetrapyrene derivative | π-π | Stable and dispersed, conductive | Sensors |
| –OH | DNA | Hydrogen bond interaction | Stable and dispersed, good solubility | Biomedicine |
| –OH | DXR | Hydrogen bond interaction | Stable and dispersed, good solubility | Drug carriers |
| -COOH | SDBS | Ion interaction | Stably dispersed, conductive | Packaging |
| -COO- | Hydrazine | Electrostatic interaction | Stably dispersed | — |
Alfa Chemistry's Technical Strengths
Alfa Chemistry has a team of professional chemists and technicians who has established long-term cooperative relationships with many well-known enterprises and research institutions. Alfa Chemistry not only can design functional target groups, establish structural feature models, and guide the synthesis of new products, but also can perform specific functional modifications to graphene products according to customer needs.
References
- Georgakilas V, et al. (2016). "Noncovalent Functionalization of Graphene and Graphene Oxide for Energy Materials, Biosensing, Catalytic, and Biomedical Applications." Chemical Reviews. 116(9), 5464-5519.
- Kim T. Y, et al. (2010). "Synthesis of Phase Transferable Graphene Sheets Using Ionic Liquid Polymers." ACS Nano . 4(3), 1612-1618.
