Three-Dimensional Phosphorus-Doped Graphitic‑C₃N₄ Self-Assembly with NH₂‑Functionalized Carbon Composite Materials for Enhanced Oxygen Reduction Reaction

Oxygen reduction reaction (ORR) is the major reaction that occurs at the cathodes of fuel cells and metal–air batteries. Development of inexpensive, active, and durable heteroatom doped carbon-based ORR catalysts can lead to significant cost reduction of these electrochemical energy devices, which therefore has recently attracted enormous research attentions. This work reports a three-dimensional porous composite (P-<i>g</i>-C₃N₄@NH₂–CB) for the highly efficient ORR catalyst. P-<i>g</i>-C₃N₄@NH₂–CB was prepared by mixing phosphorus-doped graphitic carbon nitride nanosheets (P-<i>g</i>-C₃N₄ NSs) with NH₂-functionalized carbon black (NH₂–CB) via a novel self-assembly approach. The NH₂–CB was rationally chosen as the spacer that enables the self-assembled with the P-<i>g</i>-C₃N₄ NSs driven by the electrostatic interaction. The intercalation of NH₂–CB induces the transformation of 2-D P-<i>g</i>-C₃N₄ NSs into a 3-D composites material of higher surface area, thereby exposing more ORR active sites. The P-<i>g</i>-C₃N₄@NH₂–CB exhibited a remarkable ORR activity with an electron transfer number of 3.83 and Tafel slope of 89 mV dec^–1 in alkaline electrolyte, which is comparable to the ORR performance on Pt/Vulcan XC-72. It is found that the incorporated P atoms as well as employing NH₂–CB spacer not only reduces the overpotential of ORR, but also enhances the ORR activity of carbon nitride-based materials, owing to the synergistic effect between P and N in tri-s-triazine rings of carbon nitrides and the optimum interaction between the oppositely charged P-<i>g</i>-C₃N₄ and NH₂–CB

Additional file 1: of Associations between aspirin use and the risk of cancers: a meta-analysis of observational studies

Table S1. Summary table. Table S2. Subgroup analysis of relative risk of gastric cancer. Table S3. Subgroup analysis of relative risk of esophagus cancer. Table S4. Subgroup analysis of relative risk of colorectal cancer. Table S5. Subgroup analysis of relative risk of hepato-biliary cancer. Table S6. Subgroup analysis of relative risk of pancreatic cancer. Table S7. Subgroup analysis of relative risk of lung cancer. Table S8. Subgroup analysis of relative risk of breast cancer. Table S9. Subgroup analysis of relative risk of ovarian cancer. Table S10. Subgroup analysis of relative risk of endometrial cancer. Table S11. Subgroup analysis of relative risk of prostate cancer. Table S12. Subgroup analysis of relative risk of renal cancer. Table S13. Subgroup analysis of relative risk of bladder cancer. Table S14. Subgroup analysis of relative risk of brain tumor. Table S15. Subgroup analysis of relative risk of head and neck cancers. Table S16. Subgroup analysis of relative risk of skin cancer. Table S17. Subgroup analysis of relative risk of lymphoma. Table S18. Subgroup analysis of relative risk of leukemia. (DOC 549 kb

Selective Oxidation of 1,2-Propanediol in Alkaline Anion-Exchange Membrane Electrocatalytic Flow Reactors: Experimental and DFT Investigations

Electrocatalytic oxidation of polyhydric alcohols represents an important route for coproduction of biorenewable chemicals and energy. However, the governing factors leading to high product selectivity remain unclear. Herein, we investigate the selective oxidation of 1,2-propanediol (PDO) to pyruvate or lactate in electrocatalytic reactors over carbon-supported platinum (Pt/C) and gold (Au/C) anode catalysts. PDO-fed alkaline anion-exchange membrane fuel cells successfully cogenerated electricity and valuable chemicals with peak power densities of 46.3 mW cm^–2 on Pt/C and 10.0 mW cm^–2 on Au/C. Pt/C was highly selective for primary alcohol group oxidation to lactate (86.8%) under fuel cell conditions, but Au/C yielded significant amounts of pyruvate, a product that has previously eluded heterogeneous catalytic studies on Au. Sequential oxidation of lactate to pyruvate was not observed on Au/C but did occur slowly on Pt/C. The electrode potential dependent product distribution was investigated, and it was revealed that pyruvate selectivity on Au/C was sensitive to anode potential and could be varied from 20 to 56%. On the basis of observed product distributions and linear sweep voltammetry of intermediate products, we propose that the intermediates hydroxyacetone and pyruvaldehyde, which are not stable in high pH electrolyte, can be further oxidized to pyruvate on Au/C only if they are trapped within the thick liquid diffusion layer of the carbon cloth supported catalyst layer. Density functional theory (DFT) calculations of reaction energies identified the most favorable reaction intermediates and provided insight into the likely reaction pathways

Additional file 1: of Factors influencing government insurance scheme beneficiary acceptance of the gatekeeper policy: a cross-sectional study in Wuhan, China

The detailed contents of the EUROPEP questionnaire. (DOC 29 kb

Additional file 1 of A multifunctional ‘golden cicada’ nanoplatform breaks the thermoresistance barrier to launch cascade augmented synergistic effects of photothermal/gene therapy

Supplementary Material

Chinese Version of the EQ-5D Preference Weights: Applicability in a Chinese General Population - Fig 1

<p>a-f. The Bland-Altman plots of EQ-5D scores derived from the China, UK, Japan, and Korea preference weights.</p

Distribution of EQ-5D index scores using China, UK, Japan and Korea weights.

<p>Distribution of EQ-5D index scores using China, UK, Japan and Korea weights.</p

Known-groups validity of the EQ-5D index scores using China, UK, Japan and Korea weights.

<p>Known-groups validity of the EQ-5D index scores using China, UK, Japan and Korea weights.</p

Sensitivity of the EQ-5D index scores using China, UK, Japan and Korea weights.

<p>Sensitivity of the EQ-5D index scores using China, UK, Japan and Korea weights.</p