A new study sheds light on unique property of 2-D materials -- ability to shield chemical interactions at the molecular level. Discovery of shielding effect allows scientists to control reactivity of molecules, tune activity of catalysts, and construct new generation of carbon materials.
Joint theoretical and experimental study suggested that graphene sheets efficiently shield chemical interactions. One of the promising applications of this phenomenon is associated with improving quality of 2D materials by "de-charging" of charged defect centers on the surface of carbon materials.
Another important feature is the ability to control selectivity and activity of the supported metallic catalysts M/C on the carbon substrate.
Researchers studied carbon materials with defects on the surface (such defects represent an active species, which should be shielded). Indeed, the experiments demonstrated that the defects areas are quite reactive and, as one may expect, defect sites retain high activity towards various molecules.
However, as soon as the defects were covered with few layers of graphene flakes, the distribution of reactive centers became uniform (without localized reactivity centers typical for defect areas). In other words, covering of the surface defects with graphene layers has decreased the influence of charged defects and made them "invisible" in terms of chemical interactions at the molecular level.
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The above post is reprinted from materials provided by Institute of Organic Chemistry, Russian Academy of Sciences. Note: Materials may be edited for content and length.
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