Finding efficient electrocatalysts for oxygen evolution reaction (OER) that can be effectively integrated with semiconductors is significantly challenging for solar‐driven photo‐electrochemical (PEC) water splitting. Herein, amorphous cobalt–iron hydroxide (CoFeH) nanosheets are synthesized by facile electrodeposition as an efficient catalyst for both electrochemical and PEC water oxidation. As a result of the high electrochemically active surface area and the amorphous nature, the optimized amorphous CoFeH nanosheets exhibit superior OER catalytic activity in alkaline environment with a small overpotential (280 mV) to achieve significant oxygen evolution (j = 10 mA cm−2) and a low Tafel slope (28 mV dec−1). Furthermore, CoFeH nanosheets are simply integrated with BiVO4 semiconductor to construct CoFeH/BiVO4 photoanodes that exhibit a significantly enhanced photocurrent density of 2.48 mA cm−2 (at 1.23 V vs reversible hydrogen electrode (RHE)) and a much lower onset potential of 0.23 V (vs RHE) for PEC‐OER. Careful electrochemical and optical studies reveal that the improved OER kinetics and high‐quality interface at the CoFeH/BiVO4 junction, as well as the excellent optical transparency of CoFeH nanosheets, contribute to the high PEC performance. This study establishes amorphous CoFeH nanosheets as a highly competitive candidate for electrochemical and PEC water oxidation and provides general guidelines for designing efficient PEC systems.

Objective: Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects. Design: A random-effects model was used to pool the risk estimates. Generalized least-squares regression and restricted cubic splines were used to assess the possible dose-response relationship. Subgroup analyses were conducted to examine the sources of heterogeneity. Setting: PubMed and ISI Web of Science databases up to September 2010 were searched and secondary referencing qualified for inclusion in the study. Subjects: Seventeen cohorts with 315 812 participants and average follow-up period of 15?9 years were identified. Results: Compared with the lowest fish intake (,1 serving/month or 1-3 servings/ month), the pooled relative risk (RR) of fish intake on CHD mortality was 0?84 (95 % CI 0?75, 0?95) for low fish intake (1 serving/week), 0?79 (95 % CI 0?67, 0?92) for moderate fish intake (2-4 servings/week) and 0?83 (95 % CI 0?68, 1?01) for high fish intake (.5 servings/week). The dose-response analysis indicated that every 15 g/d increment of fish intake decreased the risk of CHD mortality by 6 % (RR 5 0?94; 95 % CI 0?90, 0?98). The method of dietary assessment, gender and energy adjustment affected the results remarkably. Conclusions: Our results indicate that either low (1 serving/week) or moderate fish consumption (2-4 servings/week) has a significantly beneficial effect on the prevention of CHD mortality. High fish consumption (.5 servings/week) possesses only a marginally protective effect on CHD mortality, possibly due to the limited studies included in this group.

We report the rational design and successful preparation of p-Si/NiCoSex core/shell nanopillar array photocathodes for enhanced solar-driven photoelectrochemical hydrogen generation.

We report polymorphic CoSe2 (p-CoSe2) with mixed orthorhombic and cubic phases as a highly active electrocatalyst toward hydrogen evolution reaction (HER). The p-CoSe2 is obtained by calcining CoSex via electrodeposition at 300 °C. The results of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) demonstrated the crystal structure of p-CoSe2. The p-CoSe2 exhibits excellent electrocatalytic activity for HER with a low onset overpotential of -70 mV and a small Tafel slope of ∼30 mV/decade, which are basically state-of-the-art performance of earth-abundant electrocatalysts. The HER performance of p-CoSe2 was much higher than that of amorphous CoSex, cubic CoSe2, and CoSe. This study offers a competitive electrocatalyst for HER and opens up a new strategy to the synthesis of catalysts for energy conversion.

Dual enzymatic reactions were introduced to fabricate programmed gemcitabine (GEM) nanovectors for targeted pancreatic cancer therapy. Dual-enzyme-sensitive GEM nanovectors were prepared by conjugation of matrix metalloproteinase-9 (MMP-9) detachable poly(ethylene glycol) (PEG), cathepsin B-cleavable GEM, and targeting ligand CycloRGD to CdSe/ZnS quantum dots (QDs). The GEM nanovectors decorated with a PEG corona could avoid nonspecific interactions and exhibit prolonged blood circulation time. After GEM nanovectors were accumulated in tumor tissue by the enhanced permeability and retention (EPR) effect, the PEG corona can be removed by overexpressed MMP-9 in tumor tissue and RGD would be exposed, which was capable of facilitating cellular internalization. Once internalized into pancreatic cancer cells, the elevated lysosomal cathepsin B could further promote the release of GEM. By employing dual enzymatic reactions, the GEM nanovectors could achieve prolonged circulation time while maintaining enhanced cellular internalization and effective drug release. The proposed mechanism of the dual enzymatic reaction-assisted GEM delivery system was fully investigated both in vitro and in vivo. Meanwhile, compared to free GEM, the deamination of GEM nanovectors into inactive 2',2'-difluorodeoxyuridine (dFdU) could be greatly suppressed, while the concentration of the activated form of GEM (gemcitabine triphosphate, dFdCTP) was significantly increased in tumor tissue, thus exhibiting superior tumor inhibition activity with minimal side effects.

Sn‐based materials are identified as promising catalysts for the CO2 electroreduction (CO2RR) to formate (HCOO−). However, their insufficient selectivity and activity remain grand challenges. A new type of SnO2 nanosheet with simultaneous N dopants and oxygen vacancies (VO‐rich N‐SnO2 NS) for promoting CO2 conversion to HCOO− is reported. Due to the likely synergistic effect of N dopant and VO, the VO‐rich N‐SnO2 NS exhibits high catalytic selectivity featured by an HCOO− Faradaic efficiency (FE) of 83% at −0.9 V and an FE of > 90% for all C1 products (HCOO− and CO) at a wide potential range from −0.9 to −1.2 V. Low coordination Sn–N moieties are the active sites with optimal electronic and geometric structures regulated by VO and N dopants. Theoretical calculations elucidate that the reaction free energy of HCOO* protonation is decreased on the VO‐rich N‐SnO2 NS, thus enhancing HCOO− selectivity. The weakened H* adsorption energy also inhibits the hydrogen evolution reaction, a dominant side reaction during the CO2RR. Furthermore, using the catalyst as the cathode, a spontaneous Galvanic Zn‐CO2 cell and a solar‐powered electrolysis process successfully demonstrated the efficient HCOO− generation through CO2 conversion and storage.

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