Self-supported Co-doped FeNi carbonate hydroxide nanosheet array as a highly efficient electrocatalyst towards the oxygen evolution reaction in an alkaline solution.

The evolution of molecular hydrogen from electrochemical water splitting has currently emerged as one of the promising strategies to address the ever-increasing energy crisis and environmental pollution. The development of low-cost, highly efficient and long-term durable electrocatalysts is still challenging for practical large-scale water splitting applications. Herein, a highly crystallized Co-doped FeNi carbonate hydroxide nanosheet array was strongly grown on a conductive nickel foam (Co-FeNi CH/NF) and was used as an oxygen evolution reaction (OER) electrocatalyst. The ternary Co-FeNi CH/NF electrode exhibited an improved OER activity and good durability for at least 20 hours. The electrode delivered current densities of 10 and 500 mA cm-2 at extremely low overpotentials of 202 and 254 mV along with a small Tafel slope of 37.5 mV dec-1 in a 1.0 M KOH electrolyte solution. The incorporation of an equivalent amount of cobalt into the trigonal FeNi CH crystal lattice significantly increased the electrochemical active surface area and reduced the electron transport resistance by effectively regulating the electronic structure of the resultant electrocatalyst. These interesting observations highlight the importance of the subtle combinations of the active earth-abundant metals with electronic structure modulations.

Intestinal Microbiota Is Altered in Patients with Gastric Cancer from Shanxi Province, China.

BACKGROUND: Many diseases have been associated with intestinal microbial dysbiosis. Host-microbial interactions regulate immune function, which influences the development of gastric cancer. AIMS: The aims were to investigate the characteristics of intestinal microbiota composition in gastric cancer patients and correlations between the intestinal microbiota and cellular immunity. METHODS: Fecal samples were collected from 116 gastric cancer patients and 88 healthy controls from Shanxi Province, China. The intestinal microbiota was investigated by 16S rRNA gene sequencing. Peripheral blood samples were also collected from the 66 gastric cancer patients and 46 healthy controls. The populations of peripheral T lymphocyte subpopulations and NK cells were analyzed by flow cytometry. RESULTS: The intestinal microbiota in gastric cancer patients was characterized by increased species richness, decreased butyrate-producing bacteria, and the enrichment of other symbiotic bacteria, especially Lactobacillus, Escherichia, and Klebsiella. Lactobacillus and Lachnospira were key species in the network of gastric cancer-associated bacterial genera. The combination of the genera Lachnospira, Lactobacillus, Streptococcus, Veillonella, and Tyzzerella_3 showed good performance in distinguishing gastric cancer patients from healthy controls. There was no significant difference in enterotype distribution between healthy controls and gastric cancer patients. The percentage of CD3+ T cells was positively correlated with the abundance of Lactobacillus and Streptococcus, and CD3+ T cells, CD4+ T cells, and NK cells were associated with Lachnospiraceae taxa. CONCLUSIONS: Our study revealed a dysbiotic intestinal microbiota in gastric cancer patients. The abundance of some intestinal bacterial genera was correlated with the population of peripheral immune cells.