New Solid-state NMR Methods And MOF Anode Materials

In the first part, a modificaiton of WURST-CPMG is introduced. The WURST-CPMG pulse sequence enables:(ⅰ) observing very broad spectra due to WURST excitation, and (ⅱ) increasing the S/N ratio due to CPMG acquisition. However, strong baseline distortions may be observed, which make the extraction of the tensor information difficult. We propose a slight modification of the sequence, WURST-CPMGM, in which we skip the first M echoes and we only acquire the following ones. This simple treatment mostly eliminates the strong background signal and the ring down effects, leading to a flat baseline.In the second part, the reversible charging of a two-dimensional copper coordination polymer Cu(1,3-BDC) prepared via a hydro(solvo)thermal approach was studied for use as the anode in a Li-ion cell. It was found that this Cu(1,3-BDC) electrode delivered a reversible lithium storage capacity of up to about 565.12 mA h g-1 at 100 mA g-1, and high rate capability of 230.54 mA h g-1 at 2 A g-1, thus exhibiting one of the best lithium storage properties among the reported metal organic framework (MOF), also known as coordination polymer anodes, and the excellent electrochemical performance is also comparable with the Cu-based MOF template formed CuO and CuO/Cu2O nanostructures. The results here further recommend 2D metal coordination polymer for potential use in lithium-ion batteries.