Since the discovery of graphene, there has been tremendous interest in the synthesis of two-dimensional sheets that are single atoms or monomers thick and can be used in applications such as energy storage, catalysis, or sensing.

Xinliang Feng and his team, Technische Universität Dresden and Max Planck Institute for Polymer Research, Mainz, both Germany, have come up with a way of preparing two-dimensional supramolecular polymers (2DSPs). They use the Langmuir–Blodgett method to produce single-layer sheets of nickel bis(dithiolene) complexes.

The free-standing 2DSP sheets are 0.7–0.9 nm thick, and the lateral dimensions are in the order of square millimeters. The sheets can be transferred intact onto other substrates. The efficiency of the 2DSPs in the hydrogen evolution reaction was subsequently investigated, and their performance was found to be outstanding compared to other similar catalysts. These free-standing 2DSPs are promising candidates for electrode materials that can be used in energy applications.

• Large-Area, Free-Standing, Two-Dimensional Supramolecular Polymer Single-Layer Sheet for Highly Efficient Electrocatalytic Hydrogen Evolution,
  Renhao Dong, Martin Pfeffermann, Haiwei Liang, Zhikun Zheng, Xiang Zhu, Jian Zhang, Xinliang Feng,
  Angew. Chem. Int. Ed. 2015.
  DOI: 10.1002/anie.201506048