Novel metalloporphyrin covalently functionalized polyphosphazene nanotubes for boosting the hydrogen evolution reaction.

Herein, we demonstrate the first example of a novel electrocatalytic hybrid system (CoTPP-PZSNT) with a push-pull motif to boost hydrogen evolution reaction (HER) activity. CoTPP-PZSNT exhibits an efficient HER activity, with overpotentials of 157 and 109 mV at 10 mA cm-2 in 1.0 M KOH and 0.5 M H2SO4 solutions, respectively. The HER performance of CoTPP-PZSNT outperforms many previously reported HER catalysts, due to efficient charge transfer between each component.

Acenaphthenediimine complex-bridged porphyrin porous organic polymer with enriched active sites as a robust water splitting electrocatalyst.

To realize efficient water splitting, a highly promising hydrogen evolution reaction (HER) electrocatalyst is needed for the generation of hydrogen. Herein, we demonstrate a novel acenaphthenediimine complex-bridged porphyrin porous organic polymer (NiTAPP-NiACQ) with enriched active metal sites and hierarchical pores. The as-prepared NiTAPP-NiACQ exhibits good long-term durability and remarkable HER performance in 1.0 M KOH with a low overpotential of 117 mV at 10 mA cm-2, which is comparable to many previously reported electrocatalytic HER systems. Furthermore, a simple water-alkali electrolyzer using NiTAPP-NiACQ as the cathode requires a small cell voltage of 1.59 V to deliver a current density of 10 mA cm-2 at room temperature, along with outstanding durability. NiTAPP-NiACQ features not only a metal ion as the catalytic active center in the porphyrin core but also metal ion coordination on the anthraquinone component to promote HER performance, enabling multiple metal ions as the electrocatalytic active sites for the HER reaction. The excellent HER activity of NiTAPP-NiACQ is ascribed to a combination of mechanisms. These findings highlight the viability of porphyrin-derived porous organic polymers in energy conversion processes.

Efficient oxygen evolution reaction from iron-molybdenum nitride/molybdenum oxide heterostructured composites.

Integrating various active sites into a multi-component system might significantly enhance the oxygen evolution reaction (OER) performance. Herein, the as-prepared iron-molybdenum nitride/molybdenum oxide (Fe-Mo5N6/MoO3-550) composite electrocatalyst under optimum conditions demonstrates excellent electrocatalytic performance toward OER and reaches current densities of 10 and 20 mA cm-2 at overpotentials of 201 and 216 mV, respectively. The OER performance of Fe-Mo5N6/MoO3-550 exceeds that of most previously reported electrocatalytic systems. The significant improvement in the OER performance is ascribed to a combination of mechanisms. The strong electronic interactions among the Fe, Mo5N6 and MoO3 species can accelerate the OER reaction kinetics, which contributes to the OER performance. This work provides new insights into the construction of efficient electrocatalytic materials with inexpensive metals.

Boosted hydrogen evolution reaction for a nitrogen-rich azo-bridged metallated porphyrin network.

The potential of porous organic polymers (POPs) toward electrocatalytic water splitting have attracted considerable scientific attention, due to their high specific surface areas, superlative porosity and diverse electronic structures; yet it remains challenging. Herein, we report a facile synthesized novel nitrogen-rich azo-bridged metallated porphyrin POP (CoTAPP-CoTNPP) for improving the hydrogen evolution reaction (HER) activity. The incorporation of the cobalt porphyrins and the azo groups endows CoTAPP-CoTNPP with effective charge transfer efficiency and large π-conjugated porous frameworks, thus enhancing the HER performance. Origins of the excellent HER performance of the material are evaluated using a series of structural and electrochemical measurements. Remarkably, CoTAPP-CoTNPP exhibits low overpotentials of 103 and 170 mV to reach 10 mA cm-2 in acidic and alkaline media, respectively, outperforming many previously reported HER electrocatalysts. These results demonstrate the enormous potential of the as-prepared azo-linked porphyrin POP for electrocatalytic water splitting.

Efficient hydrogen generation of a cobalt porphyrin-bridged covalent triazine polymer.

Hydrogen production obtained by electrocatalytic water splitting exhibits great promise in addressing both energy shortage and environmental contamination. Herein, we prepared a novel cobalt porphyrin (CoTAPP)-bridged covalent triazine polymer (CoTAPPCC) by covalently linking CoTAPP with cyanuric chloride (CC) for catalytic hydrogen evolution reaction (HER). Both experimental techniques and density functional theory (DFT) calculations were used to evaluate the correlation of HER activity with molecular structures. Benefiting from the strong electronic interactions between the CC unit and the CoTAPP moiety, a standard current density at 10 mA cm-2 is obtained for CoTAPPCC with a low overpotential of 150 mV in acid, which is comparable to or better than the best records reported previously. Additionally, a competitive HER activity in basic medium is obtained for CoTAPPCC. The strategy reported herein is valuable for designing and developing porphyrin-based efficient HER electrocatalysts.

A tin porphyrin axially-coordinated two-dimensional covalent organic polymer for efficient hydrogen evolution.

Herein, we demonstrate a facile strategy for constructing an efficient and stable hydrogen evolution reaction (HER) catalyst, i.e. a tin porphyrin axially-coordinated 2D covalent organic polymer (SnTPPCOP). SnTPPCOP exhibits promising HER activity with a low overpotential of 147 mV at 10 mA cm-2 due to its unique structural properties, ranking among the best records reported recently.

Strongly Coupled Nitrogen-Doped Mo2C@CoNi Alloy Hybrid Architecture toward Efficient Hydrogen Evolution Reaction.

Development of high-efficiency electrocatalysts for water splitting is a promising channel to produce clean hydrogen energy. Herein, we demonstrate that the combination of nitrogen-doped Mo2C and CoNi alloy to form a hybrid architecture is an effective way to produce hydrogen from electrochemical water splitting. Benefiting from a combination of mechanisms, the optimized N-Mo2C@CoNi-650 shows remarkable hydrogen evolution reaction (HER) activity with small overpotentials of 35, 123, and 220 mV to reach the current density of 10, 50, and 100 mA cm-2 in alkaline media, respectively, outperforming most previously reported HER electrocatalysts. The efficient electrocatalytic performance is ascribed to the highly exposed active sites, fast reaction kinetics, and improved charge-transfer steaming from the synergistic effect between each component. This work presents a new insight into designing and preparing highly efficient electrocatalysts toward the HER.

Association of roasting meat intake with the risk of esophageal squamous cell carcinoma of Kazakh Chinese via affecting promoter methylation of p16 gene.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) incidence is high in Kazak Autonomous Prefecture, Xinjiang, China. Roasting food has been reported to be related with the risk of various cancers and is very popular in the area, and may be related with the risk of ESCC. The promoter methylation inactivation of p16 gene can increase the risk of ESCC. Thus, we want to know whether long-term roasting food is related with the risk of ESCC by effecting the promoter methylation of p16 gene. MATERIALS AND METHODS: Ninety ESCC patients and 60 healthy subjects were recruited from Kazak Autonomous Prefecture. MassARRAY was used to detect p16 promoter methylation in ESCC tissues, as well as in normal esophageal tissues. The association between the p16 promoter methylation and daily roasting meat intake was examined. RESULTS: Daily roasting meat intake was related with the risk of ESCC (p<0.01) and the mean CpG methylation rates of p16 promoter (p<0.01). In ESCC patients, the mean methylation rates of CpG 11-12 and CpG 33-34-35 were 29.4% and 37.4%, respectively, which was significantly higher than the rates in normal esophageal tissues (16.7% and 12.4%, respectively; p<0.01). The methylation of p16 promoter is also related with daily roasting meat intake (p<0.01) in Kazakh Chinese with ESCC. For the CpG methylation of the p16 promoter in the well, moderately and poorly differentiated ESCC, there are significant differences (p<0.05) for the 19 CpG units in the ESCC and controls. CONCLUSION: Roasting meat intake was associated with the risk of ESCC via effects on the methylation of p16 promoter. These results suggest roasting food intake should be limited in the diet.