4 research outputs found
Enhanced graphitic domains of unreduced graphene oxide and the interplay of hydration behaviour and catalytic activity
Previous studies indicate that the properties of graphene oxide (GO) can be
significantly improved by enhancing its graphitic domain size through thermal
diffusion and clustering of functional groups. Remarkably, this transition
takes place below the decomposition temperature of the functional groups and
thus allows fine-tuning of graphitic domains without compromising with the
functionality of GO. By studying the transformation of GO under mild thermal
treatment, we directly observe this size enhancement of graphitic domains from
originally 40 nm2 to 200 nm2 through an extensive transmission electron
microscopy (TEM) study. Additionally, we confirm the integrity of the
functional groups during this process by comprehensive chemical analysis. A
closer look into the process confirms the theoretically predicted relevance for
the room temperature stability of GO. We further investigate the influence of
enlarged graphitic domains on the hydration behaviour of GO and catalytic
performance of single-atom catalysts supported by GO. Surprisingly, both, the
water transport and catalytic activity are damped by the heat treatment. This
allows us to reveal the critical role of water transport in laminated 2D
materials as catalysts