With the increasing demand of lithium-ion batteries in recent decades, the growing waste from the electrode materials of lithium-ion batteries has become an urgent problem. Lithium cobalt oxide (LiCoO 2 ), used as the cathode materials of lithium-ion batteries, exhibits high capacity and excellent stability but also a high price. To recycle the LiCoO 2 cathode, it is desirable to develop solvents for the dissolution of LiCoO 2 . At present, the dissolution of LiCoO 2 still requires strong acid or a high temperature. Here, benign polyethylene glycol-based deep eutectic solvents (DES) were designed and further used for the dissolution of LiCoO 2 under mild conditions with high solubility. This work provides a new route for the green recovery of lithium-ion cathodes with high efficiency and low energy consumption.

The introduction of optoelectronic functions into viscoelastic polymers can yield highly sophisticated soft materials for biomedical devices and autonomous robotics. However,v iscoelasticity and excellent optoelectronic properties are difficult to achieve because the presence of al arge number of p-conjugated moieties drastically stiffens apolymer. Here,w er eport av ariation of additive-free viscoelastic conjugated polymers (VE-CPs) at room temperature by using an intact p-conjugated backbone and bulky,yet flexible, alkyls ide chains as "internal plasticizers." Some of these polymers exhibit gel-and elastomer-like rheological behaviors without cross-linking or entanglement. Furthermore,b inary blends of these VE-CPs exhibit an ever-seen-before dynamic miscibility with self-restorable and mechanically induced fluorescence color changes.

Recently, starch nanoparticles have attracted widespread attention from various fields. In this study, a new strategy for preparing covalent-cross-linked starch nanoparticles was developed using boron ester bonds formed between debranched starch (DBS) and borax. The nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), differential scanning calorimeter (DSC), and thermogravimetric analysis (TGA). The obtained nanoparticles were spherical with a size of 100−200 nm. The formation of boron ester bonds was confirmed by FTIR. The as-prepared starch nanoparticle exhibited a low relative crystallinity of 13.6%−23.5%. Compared with pure starch film, the tensile strength of starch film with 10% starch nanoparticles increased about 45%, and the elongation at break percentage of starch film with 5% starch nanoparticles increased about 20%. The new strategy of forming starch nanoparticles by using boron ester bonds will advance the research of carbohydrate nanoparticles.

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The catalytic oxidation of gaseous HCl (containing a small amount of HF) to Cl 2 is important and highly desired for chlorine recycling in the fluorochemical industry. In the present work, a series of Al-doped MgF 2 (Al− MgF 2 ) materials were synthesized via a sol−gel method, followed by calcination at different temperatures and then these synthesized Al−MgF 2 materials were used as supports to prepare RuO 2 /Al−MgF 2 catalysts by an incipient impregnation method. These developed catalysts were evaluated in the oxidation of HCl with an upper-bound HF concentration of 400 ppm, as is common in the fluorochemical industry. Specific attention was paid to investigating the effects of calcination temperature for preparing Al−MgF 2 supports on the activity and stability of the resultant catalysts. It is found that at an optimal calcination temperature, Al can be incorporated into the framework of rutile structure MgF 2 , which can further modify the cell parameters of MgF 2 close to those of RuO 2 , modulate the interactions between RuO 2 and the support, and yet affect the chemical environment of RuO 2 to enhance the catalytic activity and stability. The study on the catalytic kinetics reveals that the estimated apparent activation energy is in line with the incorporated amount of Al into the framework of MgF 2 and shows an inverted volcano relationship with the calcination temperature for preparing Al−MgF 2 supports. The lowest apparent activation energy of RuO 2 /Al−MgF 2 can be achieved when the Al−MgF 2 composite is calcined at 400 °C, and the resultant catalyst shows long-term stability with high activity for the oxidation of HCl containing a small amount of HF.