Metal‐organic frameworks (MOFs) have attracted increasing attention as a promising electrode material for the oxygen evolution reaction (OER). Comprehending catalytic mechanisms in the OER process is of key relevance for the design of efficient catalysts. In this study, two types of Co based MOF with different organic ligands (ZIF‐67 and CoBDC; BDC=1,4‐benzenedicarboxylate) are synthesized as OER electrocatalysts and their electrochemical behavior is studied in alkaline solution. Physical characterization indicates that ZIF‐67, with tetrahedral Co sites, transforms into α‐Co(OH)2 on electrochemical activation, which provides continuous active sites in the following oxidation, whereas CoBDC, with octahedral sites, evolves into β‐Co(OH)2 through hydrolysis, which is inert for the OER. Electrochemical characterization reveals that Co sites coordinated by nitrogen from imidazole ligands (Co−N coordination) are more inclined to electrochemical activation than Co−O sites. The successive exposure and accumulation of real active sites is responsible for the gradual increase in activity of ZIF‐67 in OER. This work not only indicates that CoMOFs are promising OER electrocatalysts but also provides a reference system to understand how metal coordination in MOFs affects the OER process.
ObjectivesSeveral COVID-19 vaccines list “uncontrolled epilepsy” as a contraindication for vaccination. This consequently restricts vaccination against COVID-19 in patients with epilepsy (PWE). However, there is no strong evidence that COVID-19 vaccination can exacerbate conditions in PWE. This study aims to determine the impact of COVID-19 vaccination on PWE.MethodsPWE were prospectively recruited from 25 epilepsy centers. We recorded the seizure frequency at three time periods (one month before the first vaccination and one month after the first and second vaccinations). A generalized linear mixed-effects model (GLMM) was used for analysis, and the adjusted incidence rate ratio (AIRR) with 95% CI was presented and interpreted accordingly.ResultsOverall, 859 PWE were included in the analysis. Thirty-one (3.6%) and 35 (4.1%) patients were found to have increased seizure frequency after the two doses, respectively. Age had an interaction with time. The seizure frequency in adults decreased by 81% after the first dose (AIRR=0.19, 95% CI:0.11–0.34) and 85% after the second dose (AIRR=0.16, 95% CI:0.08–0.30). In juveniles (<18), it was 25% (AIRR=0.75, 95% CI:0.42–1.34) and 51% (AIRR=0.49, 95% CI:0.25–0.95), respectively. Interval between the last seizure before vaccination and the first dose of vaccination (ILSFV) had a significant effect on seizure frequency after vaccination. Seizure frequency in PWE with hereditary epilepsy after vaccination was significantly higher than that in PWE with unknown etiology (AIRR=1.95, 95% CI: 1.17–3.24). Two hundred and seventeen (25.3%) patients experienced non-epileptic but not serious adverse reactions.DiscussionThe inactivated COVID-19 vaccine does not significantly increase seizure frequency in PWE. The limitations of vaccination in PWE should focus on aspects other than control status. Juvenile PWE should be of greater concern after vaccination because they have lower safety. Finally, PWE should not reduce the dosage of anti-seizure medication during the peri-vaccination period.
Hydrogen energy is considered a competitive and environmentally friendly carrier owing to its high calorific value, abundant reserves, carbon-free emission, and renewability. Water splitting for sustainable production of hydrogen from water via sunlight or clean energy derived electricity has attracted paramount attention. Photocatalytic water splitting provides a clean solution to produce hydrogen by taking advantage of abundant solar power. Due to their unique physico-chemical properties, metal/metal oxide based composite electrospun semiconductor photocatalysts show great potential to supplant some of the non-oxide photocatalysts and other nanostructures in water splitting. The key issues to the commercialization and scale-up production remain on the fabrication, modification and performance of photocatalysts. In this review article, we showcase recent significant progress in the fabrication of semiconductor photocatalysts toward water splitting based on versatile electrospinning. The modification and performance improving strategies for a wide range of metal/metal oxide (single, mixed, metal/carbon cocatalysts) electrospun semiconductors including the structure and compositional engineering are presented. Furthermore, we also discuss the challenges and future perspectives of electrospinning toward the rational design and facile fabrication of photocatalysts.
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