Preparation of Al₂O₃–CeO₂ by Hydrothermal Method Supporting Copper Oxide for the Catalytic Oxidation of CO and C₃H₈

A series of Al2O3–CeO2 carriers were synthesized by hydrothermal method, and CuO/Al2O3–CeO2 catalysts were prepared by ultrasound-assisted impregnation for the catalytic oxidation of CO and C3H8. These prepared samples have been characterized by XRD, BET, TEM, XPS, and other techniques. The 15 wt % CuO/A1C1 catalyst exhibited the best catalytic activity, and the light-off temperatures (T50) of CO and C3H8 were 67 and 325 °C, respectively. XRD results showed that the dispersion of CuO on the catalyst surface was improved by the introduction of CeO2 into the CuO/Al2O3 catalyst. Besides, with the addition of CeO2 content, the specific surface area and pore volume of the sample gradually decrease. XPS results suggest that the synergistic effect (Ce3+ + Cu2+ ↔ Ce4+ + Cu+) is conducive to the generation of oxygen vacancies and improves the activity of the catalyst. Both H2-TPR and O2-TPD temperatures shift toward lower temperatures, indicating that redox reactions are more likely to occur. Finally, based on the results of in situ DRIFTS, the surface Cu+ species obtained from the reduction of Cu2+ play a crucial role in the catalytic oxidation of CO and C3H8

Hydrothermal Synthesis of a Ce–Zr–Ti Mixed Oxide Catalyst with Enhanced Catalytic Performance for a NH₃‑SCR Reaction

A series of mesoporous CeZrTiOx catalysts were prepared by a facile hydrothermal method. Compared with CeTiOx catalysts synthesized under the same conditions, the catalytic activity and anti-SO2 performance of the Ce1Zr1TiOx catalyst are greatly improved, and at the gas hourly space velocity (GHSV) of 60 000 h–1, the NOx removal efficiency is maintained at 90% in the temperature range of 290–500 °C. The catalytic effect of ZrO2 on the Ce–Ti catalyst NH3-SCR activity was elucidated through a series of characterizations. The results revealed that the doping of Zr could significantly improve and optimize the structure of Ce–Ti catalysts. At the same time, due to the doping of Zr, the synergistic effect between Ce and Zr in the CeZrTiOx catalyst can effectively increase oxygen mobility, total acid content, and surface adsorbed oxygen species and lead to a larger pore volume. In addition, the introduction of ZrO2 made the transformation of Ce4+ into Ce3+ more obvious, and the 2Ce4+ + Zr2+ ↔ 2Ce3+ + Zr4+ reaction greatly improved the reducibility of Ce1Zr1TiOx. Among them, the improvement of SCR performance and H2O/SO2 tolerance is due to the electronic interaction between Zr and Ce

Dietary Antioxidant-Constructed Nanodrugs Can High-Efficiently Kill Cancer Cells while Protecting Noncancer Cells

Despite great advances, the development of cancer drugs that can efficiently kill cancer cells while protecting noncancer cells has not been achieved. By using only dietary antioxidants vitamin C (VC) and (R)-(+)-lipoic acid (LA), we herein develop a nanodrug VC@cLAV featuring the above function. After entering cells, cLAV dissociates into LA and DHLA (dihydrolipoic acid, reduced form of LA) and releases VC and DHA (dehydroascorbate, oxidized form of VC). In cancer cells, the two redox pairs recycle each other and dramatically promote the intracellular reactive oxygen species production to kill cancer cells at low doses comparable to cytotoxic drugs. Oppositely in noncancer cells, the LA/DHLA and VC/DHA pairs exert anti-oxidant action to actively protect the organism by preventing the normal cells from oxidative stress and repairing cells suffering from oxidative stress. When compared with the first-line cytotoxic drug, VC@cLAV displayed superior therapeutic outcomes yet without side effects in diverse tumor models including patient-derived xenograft (PDX). This drug with efficient cancer cell killing and noncancer cell protection represents a new cancer therapy