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The efficient coupling of light absorbers with catalysts is the most critical step in the multielectron transfer process for CO2 conversion. Here a heterogenized photoconversion system consisting o...

Utilizing solar energy as a sustainable means of controlling the nitrogen pollutant is proposed. The photochemical conversion of nitrate (NO3−) to dinitrogen (N2) without using chemical reductants is an ideal solution but difficult to be realized. Here we demonstrate a successful case of solar denitrification (with 0.1–10 mM nitrate) coupled with in situ water splitting (without chemical reductants) by developing a ternary composite photocatalyst composed of TiO2, Cu–Pd bimetals, and reduced graphene oxide (rGO) (Cu–Pd/rGO/TiO2). Direct transformation of NO3− to N2 occurs on Cu–Pd/rGO/TiO2via using in situ H2 generated from water splitting in a broader pH range with achieving near 100% conversion and selectivity to N2 while it is not possible at all with rGO/TiO2 and Cu–Pd/TiO2. The unique activity is ascribed to the synergic action of Cu as a co-catalyst for nitrate-to-nitrite conversion, Pd for nitrite-to-dinitrogen conversion, and rGO for the enhanced charge separation/transfer and H2 production. The combined roles of Cu–Pd and rGO in retarding the charge recombination and accelerating the electron transfer from TiO2 to NO3− are confirmed by monitoring the time-resolved photoluminescence and slurry-type photocurrent generation, respectively. The in situ water splitting on Cu–Pd/rGO/TiO2 was confirmed by the concurrent H2 and O2 evolution and the in situ generated H2 was immediately consumed in the presence of nitrate. The introduction of rGO enabled the denitrification even under visible light (up to 450 nm) and the apparent quantum yield (AQY) of N2 production reached a maximum of 4.9% at 320 nm. The proposed composite photocatalytic system realizes the selective solar conversion for chemical reductant-free denitrification (nitrate to N2) by coupling nitrate reduction and water oxidation.

Background This study aimed to investigate the recent prevalence, management, and comorbidities of diabetes among Korean adults aged ≥30 years by analyzing nationally representative data. Methods This study used data from the Korea National Health and Nutrition Examination Survey from 2016 to 2018, and the percentage and total number of people ≥30 years of age with diabetes and impaired fasting glucose (IFG) were estimated. Results In 2018, 13.8% of Korean adults aged ≥30 years had diabetes, and adults aged ≥65 years showed a prevalence rate of 28%. The prevalence of IFG was 26.9% in adults aged ≥30 years. From 2016 to 2018, 35% of the subjects with diabetes were not aware of their condition. Regarding comorbidities, 53.2% and 61.3% were obese and hypertensive, respectively, and 72% had hypercholesterolemia as defined by low-density lipoprotein cholesterol (LDL-C) ≥100 mg/dL in people with diabetes. Of the subjects with diabetes, 43.7% had both hypertension and hypercholesterolemia. With regard to glycemic control, only 28.3% reached the target level of

Next-generation electrocatalysts with smart integrated designs, maximizing the chemical cascade synergy for sustainable hydrogen production, are needed to address the urgent environmental threats, but scalable synthesis of precisely architectured nanohybrids rendering a few-nanometer interfacial controllability to augment the catalytic reactivity and operational stability is a major bottleneck. Herein, by inventing a surface-confined lateral growth of nanometer-thin and nanoporous two-dimensional (2D)-Pt on NiFe-LDH nanosheets, a highly reactive 2D-2D interfacially integrated nanoplatform is synthesized for an alkaline hydrogen evolution reaction (HER) which not only extracts high Pt-atomic utilization efficiency but also synergistically accelerates the water dissociation and hydrogen generation cascade on the colocalized Pt/M(OH)

Background This report presents the recent prevalence and comorbidities related to diabetes in Korea by analyzing the nationally representative data. Methods Using data from the Korea National Health and Nutrition Examination Survey for 2013 to 2014, the percentages and the total number of subjects over the age of 30 years with diabetes and prediabetes were estimated and applied to the National Population Census in 2014. Diagnosis of diabetes was based on fasting plasma glucose (≥126 mg/dL), current taking of antidiabetic medication, history of previous diabetes, or glycosylated hemoglobin (HbA1c) ≥6.5%. Impaired fasting glucose (IFG) was defined by fasting plasma glucose in the range of 100 to 125 mg/dL among those without diabetes. Results About 4.8 million (13.7%) Korean adults (≥30 years old) had diabetes, and about 8.3 million (24.8%) Korean adults had IFG. However, 29.3% of the subjects with diabetes are not aware of their condition. Of the subjects with diabetes, 48.6% and 54.7% were obese and hypertensive, respectively, and 31.6% had hypercholesterolemia. Although most subjects with diabetes (89.1%) were under medical treatment, and mostly being treated with oral hypoglycemic agents (80.2%), 10.8% have remained untreated. With respect to overall glycemic control, 43.5% reached the target of HbA1c

The development of efficient and yet economic photocatalysts that can utilize solar light is crucial for the sustainable future. We report a simple approach to introduce a bidentate type of metal coordination site in polymeric carbon nitride (PCN) by an in situ keto–enol cyclization route of acetylacetone and urea to incorporate a metal chelating pyrimidine derivative into the molecular framework of PCN. The resulting new metal coordination sites provide both N- and O-complexing ligands unlike the unmodified PCN that has N-ligands only. As a proof-of-concept experiment, we introduced Al3+ ions into these coordination sites, which induced significant enhancements in visible light photocatalytic activities for organic pollutant degradation and H2 evolution as compared to those of bulk PCN and the conventional “nitrogen pot” metal-coordinated PCN. The optimized Al loading was as low as 0.32 wt %. The photocatalytic activities sensitively depended on the Al incorporation, and the Al-incorporated sample demons...

Single-step green synthesis of zinc blende ZnSe quantum dots (QDs) is performed using sodium selenide and zinc stearate. The present method is non-toxic and is considered reasonably green route where stearate ions released during the reaction act as surfactant. The size quantisation effect is revealed by blue shifted absorption bands with a band-gap energy of ~2.9 eV with respect to bulk ZnSe band-gap of 2.7 eV. Photoluminescence measurement with FWHM