Carlo Nervi

Lithium-ion batteries (LIBs) are fundamental for the energetic transition necessary to contrast climate change. The characteristics of cathode active materials (CAMs) strongly influence the cell performance, so improved CAMs need to be developed. Currently, Li(Ni0.8Mn0.1Co0.1)O2 (NMC811) is state-of-the-art among the cathodic active materials. The aim of this work is the optimization of the procedure to produce NMC811: two different syntheses were investigated, the co-precipitation and the self-combustion methods. For a better understanding of the synthesis conditions, three different types of atmospheres were tested during the calcination phase: air (partially oxidizing), oxygen (totally oxidizing), and nitrogen (non-oxidizing). The synthesized oxides were characterized by X-ray Powder Diffraction (XRPD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), Inductively Coupled Plasma (ICP), and Particle Size Distribution (PSD). The most promising materials were tested in a half-cell set up to verify the electrochemical performances. The procedure followed during this study is depicted in the graphical abstract. The oxidizing atmospheric conditions turned out to be the most appropriate to produce NMC811 with good electrochemical properties.

This study aimed to demonstrate the behavior of different complexes using IR spectroelectrochemistry (SEC), a technique that combines IR spectroscopy with electrochemistry. Four different Mn and Re catalysts for electrochemical CO2 reduction were studied in dry acetonitrile. In the case of Mn(apbpy)(CO)3Br (apbpy = 4(4-aminophenyl)-2,2′-bipyridine), SEC suggested that a very slow catalytic reduction of CO2 also occurs in acetonitrile in the absence of proton donors, but at rather negative potentials. In contrast, the corresponding Re(apbpy)(CO)3Br clearly demonstrated slow catalytic conversion at the first reduction potential. Switching to saturated CO2 solutions in a mixture of acetonitrile and 5% water as a proton donor, the SEC of Mn(apbpy)(CO)3Br displayed a faster catalytic behavior.