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An efficient ZrO2–doped Cu/SiO2catalyst was fabricated through hydrolysis precipitation method (HP) and used to produce ethylene glycol (EG) through dimethyl oxalate (DMO) hydrogenation. The states for zirconia on copper catalyst and roles in DMO hydrogenation were investigated through various characterization tools, including N2physical adsorption, XRD, H2–TPR, Methyl glycolate–TPD–MS, XPS, XAES as well. Compared with common ammonia evaporation and co–precipitation methods used in catalyst preparation, this HP method is found to effectively suppress the agglomeration and further size growth of copper nanoparticles by enhancing the interactions between copper and zirconia species. More importantly, uniform distribution of ZrO2dopant is achieved due to the pseudo-homogeneous reactions in the mixing step of catalyst preparation. A proper amount of zirconium dopant helps achieve the desirable proportion of Cu+/(Cu++Cu0) for surface copper species, especially promotes the production of Cu+species originated from Cu–ZrO2species at the interface of copper and zirconia particles. In comparison with Cu+species formed from copper phyllosilicates reduction, the Cu+sites derived from Cu–ZrO2species show higher adsorption ability of MG, an important intermediate species in ethylene glycol production. These adsorbed MG molecules further react with atomic hydrogen shifted from adjacent metallic copper surface, leading to a higher catalytic behavior. For the EG production via DMO hydrogenation, the turnover frequency (TOF) normalized by Cu0species on CuZr/SiO2catalyst is 1.8 times than that of traditional Cu/SiO2counterpart. Due to the enhanced synergy effect between Cu+and Cu0active sites, a lower activation energy of ester hydrogenation on this ZrO2–doped Cu/SiO2catalyst is believed to be responsible for the significant improvement.

We report a highly efficient ZnO-CeO2/SBA-15 catalyst prepared by solid-state grinding method with organic template. The limited space between the template and the silica wall of SBA-15 and the strong interaction between metal ions and template improve the dispersion of metal oxides, which help obtain more effective acid sites, resulting in a 1,3-butadiene selectivity as high as ˜45%.

Lead halide perovskites are excellent candidates for photoelectronic and photovoltaic applications, but the toxicity from lead is extremely concerning. Recently, Sn-based zero-dimensional lead-free perovskites synthesized using solid-state reaction techniques have become a new focus in the field. Here, we report a simple room temperature antisolvent method for the synthesis of all inorganic lead-free green emissive Cs4SnBr6(emission at 524 nm) and cyan emissive Cs3KSnBr6(emission at 500 nm) zero-dimensional perovskites. Their photoluminescence quantum yields reach 20% and 35%, respectively. In addition, they maintain their emission for 46 and 55 h in the air, respectively, compared to only 5 min of CsSnBr3. This method provides a convenient way to do the research and apply these highly emissive perovskites.

Though hydrogen is a promising energy carrier for a green future, many challenges persist. One is the difficulty in engineering storage solutions, with metal hydrides being a leading contender among solid-state strategies. To facilitate efficient searching of candidate materials, ridge regression, simple decision trees, random forest ensembles, and gradient boosting ensembles were employed to predict the energy of formation, with the random forest ensemble resulting in the lowest test set error. First, two public databases, Materials Project and HydPark, were searched for metal hydrides. Feature engineering was performed before the models were developed, resulting in electronegativity, density, atomic density, d-character, f-character, band gap, hydrogen weight fraction, magnetization, temperature, and pressure being retained. The models were then benchmarked by the lowest test error before a random forest ensemble was used to populate entries missing energy of formation. All were then scored by hydrogen storage capacity and energy of formation suitability. Readily available features, including several derived from only the chemical formula, were found to be highly predictive and so are promising for high-throughput screening of arbitrary novel hydride formulations and blends for thermodynamic feasibility.

The use of superoxide dismutase (SOD) is currently limited by its short half-life, rapid plasma clearance rate, and instability. We synthesized a small library of biofriendly amphiphilic polymers that comprise methoxy poly(ethylene glycol)-poly(cyclohexane-1,4-diyl acetone dimethyleneketal) (mPEG-PCADK) and mPEG-poly((cyclohexane86.7%, 1,5-pentanediol13.3%)-1,4-diyl acetone dimethylene ketal) (PK3) for the targeted delivery of SOD. The novel polymers could self-assemble into micellar nanoparticles with favorable hydrolysis kinetics, biocompatibility, long circulation time, and inflammation-targeting effects. These materials generated a better pH-response curve and exhibited better hydrolytic kinetic behavior than PCADK and PK3. The polymers showed good biocompatibility with protein drugs and did not induce an acidic microenvironment during degradation in contrast to materials such as PEG-block-poly(lactic-co-glycolic acid) (PLGA) and PLGA. The SOD that contained reverse micelles based on mPEG2000-PCADK exhibited good circulation and inflammation-targeting properties. Pharmacodynamic results indicated exceptional antioxidant and anti-inflammatory activities in a rat adjuvant-induced arthritis model and a rat peritonitis model. These results suggest that these copolymers are ideal protein carriers for targeting inflammation treatment.