Ag Single Atoms Anchored on CeO2 with Interfacial Oxygen Vacancies for Efficient CO2 Electroreduction.

Ag single-atom catalysts (SACs) have great potential in selective electrocatalysis of the CO2 reduction reaction (CO2RR) to CO, while it is still a challenge to achieve high current density and high atom efficiency simultaneously. Here, we present a new and simple in situ adsorption-reduction method to prepare Ag SACs supported on CeO2 (Ag1/CeO2). It is found that Ag single atoms are anchored on CeO2 through strong metal-support interaction (SMSI), and each Ag atom is accompanied with three interfacial oxygen vacancies. This Ag1/CeO2 exhibits high performance in the electrocatalytic CO2RR with a high CO faradaic efficiency (FE) of >95% under a wide potential range. The turnover frequency (TOF) value can reach 50,310 h-1 at FECO = 99.5% in H-cells. Notably, Ag1/CeO2 achieves an industrial-grade current density of 403 mA cm-2 with a high FECO of 97.2% in flow cells. Experimental results combined with density functional theory calculation revealed that this superior performance was mainly ascribed to the existence of interfacial oxygen vacancies, which lead to the formation of Ag-O-Ce3+ atomic interfaces, and activates the Ce3+-O structures as the synergistic active center of Ag, thus promoting CO2 adsorption and activation and reducing the reaction potential barrier of *COOH-to-*CO.

Cobalt Carbonate-Coated Nitrogen-Doped Carbon Nanotubes with a Sea-Cucumber Morphology for Electrocatalytic Water Splitting.

Herein, we report CoCO3-coated nitrogen-doped carbon nanotubes (NCNTs) with a sea cucumber-like morphology for water splitting. The sample with a CoCO3 content of 26.8 wt % (CoCO3/NCNT-1) exhibits excellent performance for the hydrogen evolution reaction in 1.0 M KOH electrolyte with an overpotential of 58 mV to reach 10 mA cm-2, better than the most non-noble metal catalysts reported; meanwhile, it exhibits superior electrocatalytic activity for the oxygen evolution reaction. The excellent performance of the catalyst is attributed to the nanotip effect caused by the sea-cucumber-like morphology. Notably, CoCO3/NCNT-1 can attain turnover frequencies of 2.7 s-1 at an overpotential of 50 mV, higher than that of Pt/C (1.5 s-1). A cell constructed using CoCO3/NCNT-1 as the catalyst of the electrode pair needs a low cell voltage of 1.54 V at 10 mA cm-2, superior to most reported cells. In addition, CoCO3/NCNT-1 can maintain 10 mA cm-2 for overall water splitting for 100 h without activity loss.

An Ultrastable Crystalline Acylhydrazone-Linked Covalent Organic Framework for Efficient Removal of Organic Micropollutants from Water.

As an important member of crystalline porous polymers, acylhydrazone-linked covalent organic frameworks (COFs) have gained much attention in recent years. However, the low structural stability imparts a limit on their practical applications. To tackle this problem, we report a simple strategy to increase the chemical stability of acylhydrazone-linked COFs by incorporating azobenzene groups in the conjugated framework. Through reinforcing the π-π stacking interactions between the adjacent layers with increased π-surface, it is surprising to find that the resulting materials exhibit extreme stability in harsh environments, such as in strong acid, strong base, aqueous educing agent and boiling water, even exposed to air for one year. As a proof-of-concept, such frameworks have been used to remove various organic micropollutants such as antibiotics, plastic components, endocrine disruptors, and carcinogens from water with high capacity, fast speed and excellent reusability over a wide pH range at environmentally relevant concentrations. The results provide a new avenue to significantly enhance the stability of COFs for practical applications.

[Randomized controlled study of S (+) -ismer of ibuprofen supporsitory].

OBJECTIVE: To evaluate the efficacy and safety of S (+) - ismer of ibuprofen supporsitory. METHODS: One hundred and three cases of postopterative pain and 60 cases of fever, altogether 163 patients were randomly divided into 2 groups: S (+) -ismer of ibuprofen supporsitory treatment group (one supporsitory per day for 3 days) and ibuprofen supporsitory treatment group (one supporsitory per day for 3 days). The therapeutic effect was assessed and the side-effects were observed between the 2 groups. RESULTS: After being given medicine in the first 4 hours, pain intensity difference, pain remission degree and the dropped level of fever in S (+) -ismer of ibuprofen were all bigger than those of the ibuprofen supporsitory treatment group. There was no difference in side-effects between the 2 groups. CONCLUSION: Therapeutic effect of S (+) -ismer of ibuprofen supporsitory is definite, whose action appears more quickly and stronger and it has fewer side-effects than those of ibuprofen supporsitory.