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Bimetallic AuCu/SiO2 nanosized catalysts were prepared using the wet chemical reduction technique. From among Au0.1–1.5Cu10/SiO2 catalysts, the Au0.5Cu10/SiO2 catalyst gave the highest yield of calcium lactate of 87% at a glycerol conversion of 96% when the reaction of glycerol with calcium hydroxide at a mole ratio of calcium hydroxide to glycerol of 0.8:1 was conducted under an anaerobic atmosphere at 200 °C for 2 h. The interactions between metallic Au0 and Cu0 nanoparticles facilitate calcium lactate formation. The simulation of glycerol consumption rate with an empirical power-function reaction kinetics equation yielded a reaction activation energy of 44.3 kJ∙mol−1, revealing that the catalytic reaction of glycerol with calcium hydroxide to calcium lactate can be conducted by overcoming a mild energy barrier. The synthesis of calcium lactate through the catalytic reaction of glycerol with calcium hydroxide on a bimetallic AuCu/SiO2 nanosized catalyst under a safe anaerobic atmosphere is an alternative to the conventional calcium lactate production technique through the reaction of expensive lactic acid with calcium hydroxide. [ABSTRACT FROM AUTHOR]

Fe─N─C materials with Fe─N4 sites are considered as most promising non‐precious metal‐based electrocatalysts for low‐cost proton‐exchange‐membrane fuel cells (PEMFCs). Breaking the trade‐off between activity and stability has been a long‐standing challenge in the field of acidic oxygen reduction reaction (ORR). Herein, a "top‐down" thermally‐driven strategy is developed to achieve highly active pyrrolic N‐coordinated Fe sites in a high spin state with Fe atomic cluster (Fen@Fe─Npyrr─C) and discover that the neighboring Fen cluster can synergistically stabilize such vulnerable Fe─N4 sites by inhibiting their protonation. Consequently, the Fen@Fe─Npyrr─C catalysts exhibit much enhanced ORR activity and stability, endowing PEMFCs with a high power density of 804.6 mW cm−2 (testing conditions: 80 °C, 100% RH, 2.0 bar) and over 100 h durability (at 0.5 V). These findings open up opportunities for the exploration of durable Fe─N─C ORR electrocatalysts for non‐precious metal‐based PEMFCs and other applications. [ABSTRACT FROM AUTHOR]

Alkaline earth metal (Mg2+, Ca2+, Sr2+, and Ba2+)-doped CeO2 nanocatalysts have been prepared by the successive co-precipitation and calcination method. The basicity and quantities of basic sites of alkaline earth metal-doped CeO2 nanocatalysts are remarkably influenced by the type and content of doped alkaline earth metal cations. The number of weak basic sites, Ce3+ cations, and oxygen vacancies of the doped CeO2 nanocatalysts are obviously improved when the ionic radii of alkaline earth metal cations are comparable to that of Ce4+. Catalytic activities of the doped CeO2 nanocatalysts in the synthesis of dimethyl carbonate through the reaction between methanol and CO2 increase with the increase in weak basic sites and oxygen vacancies. When the Mg0.05Ce0.95O2 nanocatalyst with larger amounts of both weak basic sites and oxygen vacancies catalyzed the reaction with a catalyst/methanol mass ratio of 1.0 : 50.0 at 4.0 MPa of CO2 and 140 °C for 4 h, the yield of dimethyl carbonate was 3.95 mmol gcat−1, which is 1.31 times that obtained on the sole CeO2 catalyst. The doping of the CeO2 nanocatalyst with alkaline earth metal obviously reduces the catalytic reaction activation energy. [ABSTRACT FROM AUTHOR]

Synthesis of sodium fatty alcohol polyoxyethylene ether acetate (C12-14 alkyl chain, oxyethylene unit number of 2, AEC-3Na) through the direct reaction between fatty alcohol polyoxyethylene ether (AEO-3) and NaOH was conducted with the use of commercial ZnO and SnO2 powders as catalysts in a solvent free and anaerobic atmosphere at 180‒220 °C. When the reaction was catalyzed by the ZnO catalyst with the NaOH/AEO-3 mol ratio of 2:1 and ZnO/AEO-3 mass ratio of 1:100 at 210 °C for 15 h, the AEC-3Na yield reached 71.8% at the selectivity of 95.9%. The ZnO catalyst with a lower basicity more effectively catalyzes the reaction than the SnO2 catalyst with a higher basicity. On the ZnO catalyst, the catalytic reaction activation is 72 kJ mol‒1. The impact of NaOH concentration on reaction rate is stronger than that of catalyst dosage. [ABSTRACT FROM AUTHOR]

In our present work, we report the synthesis of Sb-doped SnO2-coated TiO2 (TiO2@Sb-SnO2) conductive nanocomposites by hydrothermal method. Firstly, titanate whiskers were hydrothermally synthesized at 175 °C using sodium hydroxide and metatitanic acid as starting materials with a molar ratio of 4:1. And then, the TiO2@Sb-SnO2 nanocomposites were hydrothermally synthesized with the use of the as-synthesized titanate whiskers, tin tetrachloride, and antimony trichloride as starting materials at 185 °C. In the hydrothermal reaction process, Sb-doped SnO2 nanoparticles enhanced the phase transition from titanate to rutile TiO2. The oxidation states of tin and antimony elements are Sn4+, Sb5+, and Sb3+, respectively. TEM and HRTEM analyses indicated that the Sb-doped SnO2 nanoparticles with an average particle size of around 1.5 nm were coated on the surfaces of TiO2 nanoparticulates with an average particle size of around 20 nm. The TiO2@(1%)Sb-(10%)SnO2 nanocomposites had a minimum electric resistivity of 5.97 × 103 Ω·cm. Filling of the TiO2@Sb-SnO2 nanocomposites increased the electric conductivity of waterborne polyester films, endowing the polyester films with static electron dissipativity. [ABSTRACT FROM AUTHOR]