2D porous organic polymer (POP) nanosheets have attracted increasing attention for their well-defined porosity, high surface areas and pore volumes, and high stability. However, the synthesis of 2D POP nanosheets is still difficult.

Ping Chen and colleagues, Dalian Institute of Chemical Physics, China, developed a simple ionothermal method to synthesize a new class of carbonaceous POP nanosheets. Ionothermal methods use ionic liquids as a solvent, which allows high reaction temperatures. Aromatic nitrile monomers were polymerized in molten ZnCl₂ at a monomer/ZnCl₂ ratio of 1/100 at 400–500 °C. This leads to the elimination of N₂ and the formation of the carbonaceous material (pictured).

The stable nanosheets show a high surface area and micropore volume, and their properties can be tuned by varying the nature of the monomer. These characteristics, along with their high CO₂ adsorption capacity and high CO₂/N₂ selectivity, are expected to allow applications of the material in sorption, separation, and other fields.

• Synthesis of two-dimensional microporous carbonaceous polymer nanosheets and its application as high-performance CO₂ capture sorbent,
  Miao Zhang, Lin Liu, Teng He, Guotao Wu, Ping Chen,
  Chem Asian J. 2016.
  DOI: 10.1002/asia.201600396