We have investigated the effects of the molecular weight of the polyvinylidene fluoride (PVDF) binder on the electrochemical performance and mechanical integrity of the LiNi 0.33 Co 0.33 Mn 0.33 O 2 (NMC) electrodes made by a dry-powder-coating process. The microstructure, binding strength, and electrochemical behavior of the electrodes made with two types of PVDF polymers were compared. We show that a thin PVDF layer can form on the NMC particle surface after heating the PVDF to above its melting point. The microstructure and porosity of the PVDF layer depend strongly on the molecular weight of the PVDFs. With increasing molecular weight, the PVDF layer becomes more porous, improving the high-rate capacity without decreasing binding strength and long-term cycling performance of the electrodes.

Dinitrogen activation and transformation at room temperature is a goal that has been long sought after. Despite that, it remains underdeveloped due to being a challenging research area and the need for a better mechanistic understanding. Herein, we report that well-defined NbB3O2 – gas-phase clusters can activate one N2 molecule and generate the products B3N2O– and B3N2O2 –, as applying mass spectrometry and theoretical calculations. This unusual N2 activation reaction results from the different functions of the Nb and B3O2 moieties in NbB3O2 –. Theoretical calculations suggest that a catalytic cycle can be completed by the recovery of NbB3O2 –, which is achieved through the reactions of Nb and NbO with B3O2 – and B3O–, respectively. This is the first example of N2 efficient transformation at a monometallic cluster, and this method for generating dual active sites by designing proper ligands may open the way toward the development of more effective N2 fixation and functionalization methodologies.

The use of large amounts of deleterious solvents in the synthesis of metal–organic frameworks (MOFs) is one of the important factors limiting their application in industry.

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