The isolation of nanostructures consisting of 10–25 layers of a covalent organic framework is confirmed by AFM carried out on several surfaces. This is achieved by means of selective ultrasound exfoliation on the bulk layered material. TEM demonstrates the porous nature of the free‐standing layers on a carbon gird. The chemical composition of this novel 2D polymer is determined by infrared, X‐ray photoelectron, and electron‐energy‐loss spectroscopy.

We present the novel potential application of imine-based covalent organic frameworks (COFs), formed by the direct Schiff reaction between 1,3,5-tris(4-aminophenyl)benzene and 1,3,5-benzenetricarbaldehyde building blocks in m-cresol or acetic acid, named RT-COF-1 or RT-COF-1Ac/RT-COF-1AcB. The post-synthetic treatment of RT-COF-1 with LiCl leads to the formation of LiCl@RT-COF-1. The ionic conductivity of this series of polyimine COFs has been characterized at variable temperature and humidity, using electrochemical impedance spectroscopy. LiCl@RT-COF-1 exhibits a conductivity value of 6.45 × 10 S cm (at 313 K and 100% relative humidity) which is among the highest values so far reported in proton conduction for COFs. The mechanism of conduction has been determined using H andLi solid-state nuclear magnetic resonance spectroscopy. Interestingly, these materials, in the presence of controlled amounts of acetic acid and under pressure, show a remarkable processability that gives rise to quasi-transparent and flexible films showing in-plane structural order as confirmed by X-ray crystallography. Finally, we prove that these films are useful for the construction of proton exchange membrane fuel cells (PEMFC) reaching values up to 12.95 mW cm and 53.1 mA cm for maximum power and current density at 323 K, respectively.

In this Letter, we experimentally show that the room temperature ferromagnetism in the Mn-Zn-O system recently observed is associated with the coexistence of Mn 3 and Mn 4 via a double-exchange mechanism. The presence of the ZnO around MnO 2 modifies the kinetics of MnO 2 ! Mn 2 O 3 reduction and favors the coexistence of both Mn oxidation states. The ferromagnetic phase is associated with the interface formed at the Zn diffusion front into Mn oxide, corroborated by preparing thin film multilayers that exhibit saturation magnetization 2 orders of magnitude higher than bulk samples.

A stable donor–acceptor coordination complex of the elusive parent inorganic iminoborane HBNH (a structural analogue of acetylene) is reported. This species was generated via thermally induced N2 elimination/1,2‐H migration from a hydrido(azido)borane adduct NHC⋅BH2N3 (NHC=N‐heterocyclic carbene) in the presence of a fluorinated triarylborane. The mechanism of this process was also investigated by computational and isotopic labeling studies. This transformation represents a new and potentially modular route to unsaturated inorganic building blocks for advanced material synthesis.