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Developing low-cost and highly efficient electrocatalysts toward oxygen evolution reaction (OER) is of vital significance for electrochemical water splitting. Herein, we fabricate a heterostructure NiS/Ni(OH)x electrocatalyst (Ni-S-n) with regenerative oxygen vacancies via electro-deposition on nickel foam (NF) followed by a facile NaBH4 reduction. The resulting Ni-S-5 catalyst with appropriate amount of oxygen vacancies (Ovs) exhibits extraordinary activity for alkaline OER with overpotential of 142â mV and 248â mV to reach the current density of 10â mA cm-2 and 100â mA cm-2, respectively. This catalyst also shows remarkable durability with 40â h. After the stability test, the excellent OER performance is well recovered by regenerating the surface oxygen vacancies (Ovs) significantly with additional NaBH4 reduction. The Ni-S-5 catalyst still displays good activity even after repeating it three times (180â h). The surface oxygen vacancies act as vital active sites for OER. A mechanism of Ovs species transformation and regeneration based on the Ni-S-5 catalyst is proposed, which provides a new direction for exploring ultrastable and efficient OER electrocatalysts with renewable active species.
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Germination is an environmentally friendly process with no use of additives, during which only water spraying is done to activate endogenous enzymes for modification. Furthermore, it could induce bioactive phenolics accumulation. Controlling endogenous enzymes' activity is essential to alleviate granular disruption, crystallinity loss, double helices' dissociation, and molecular degradation of cereal and pseudo-cereal starch. Post-treatments (e.g. thermal and high-pressure technology) make it possible for damaged starch to reassemble towards well-packed structure. These contribute to alleviated loss of solubility and pasting viscosity, improved swelling power, or enhanced resistant starch formation. Cereal or pseudo-cereal flour (except that with robust structure) modified by early germination is more applicable to produce products with desirable texture and taste. Besides shortening duration, germination under abiotic stress is promising to mitigate starch damage for better utilization in staple foods.
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Exploring the electrocatalysts with high intrinsic activity and stability for both anode and cathode to tolerate the extremely acidic condition in proton exchange membrane water electrolyzer (PEMWE) is crucial for widespread industrial application. Herein, we constructed the bifunctional IrCox nanoalloys with abundant metal vacancies via the combination of chemical reduction and electrochemical treatment for overall water splitting. The developed IrCo0.13 exhibits ultra-low overpotentials of 238 mV for OER and 18.6 mV for HER at 10 mA cm-2 in 0.1 M HClO4, and achieves the exceptional stability of 1000 h for OER and 100 h for HER at 10 mA cm-2. Further, the cell voltage is only 1.68 V to reach a high current density of 1 A cm-2 in PEMWE with IrCo0.13 as the both cathode and anode catalytic layer, and it shows excellent corrosion resistance in acidic environment, evidenced by 415 h stable operation at 1 A cm-2. The strong electronic interactions in the Ir-Co atomic heterostructure and the in-situ generation of Co vacancies by electrochemical oxidation synergistically contribute to the enhanced activity and stability via optimizing the electronic structure of adjacent Ir active sites, enhancing the conductivity and electrochemical active surface area of the catalyst, accelerating charge transfer and kinetics. This work provides a new perspective for designing bifunctional catalysts for practical application in PEMWE.
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Comparative studies were conducted on physicochemical and technological properties of two black wheat (BW) varieties (cultivated in Shanxi Agricultural University) and their noodle-making potential. Whole-grain BW noodles showed acceptable cooking loss (≤10%) and strong antioxidant capacity. However, their textural quality remains to be enhanced. Regarding refined flour (RF) of the two BW varieties, Yunhei 14207 showed more anthocyanins, brighter color, and greater thermal stability (as reflected by the higher pasting temperature). 16W16 resulted in greater gluten content and better gluten quality of flour and higher dough stability, which contributed to the lower cooking loss and stronger tensile property of noodles. RF noodles of Yunhei 14207 displayed brighter appearance, although they had weaker tensile property. The stronger gluten network in noodles of 16W16 protected phenolics from release and degradation during drying, cooking, and steaming. Despite phenolics loss, RF noodles of Yunhei 14207 showed antioxidant capacity up to 14.97 mg TE/100 g. This research would promote understanding of characteristics of BW varieties. Considering the stronger gluten network of 16W16, its fortification in common wheat noodles at high proportion (>50%) may be promising to develop antioxidant noodles with further improved sensory quality.
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Harina , Triticum , Humanos , Harina/análisis , Triticum/química , Antioxidantes , Antocianinas , Culinaria , Glútenes/químicaRESUMEN
Oven roasting (OR) could induce hierarchical structural changes in starch, which is fundamental for altering the pasting and hydration properties of cereal flour. OR makes proteins denatured and peptide chains unraveled or rearranged. OR could alter compositions of cereal lipids and minerals. Although OR may degrade phenolics, their release from bound forms is predominant when mild/moderate conditions are exerted. Hence, some OR-modified cereals even exhibit many physiological functions, such as anti-diabetic and anti-inflammatory activity. Furthermore, these minor components interplay with starch/protein via physical entrapment, non-covalent interactions, or cross-linking. The structural changes and interactions modulate functionalities of OR-modified cereal flour, its dough/batter property, and related staple food quality. Compared with hydrothermal or high-pressure thermal treatments, proper OR even induces greater enhancement in technological quality and bioactive compounds release. Given the simple operation and low cost, it is worth utilizing OR for the development of sensory-appealing healthy staple foods.
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Grano Comestible , Harina , Harina/análisis , Grano Comestible/química , Almidón/química , Calidad de los AlimentosRESUMEN
Blue wheat starch was modified by heat-moisture treatment (HMT) with varying moisture contents (MCs). Changes in physicochemical properties were evaluated on the basis of its multi-scale structure. Following HMTs with MC below 30 %, the starch remained brighter and presented total phenolics content up to 0.20 mg/g. As treating MC increased, structural disruptions became more pronounced, which were characterized by crystallinity loss, lamellae's loosening, hydrogen bonding breakage, and debranching. Furthermore, HMTs decreased the proportion of external A chains of amylopectin. Concomitantly, modified starches showed progressively increased transition temperatures but decreased enthalpy values. Despite the swelling power decrease, HMTs with MC of 15 % showed markedly higher peak viscosity than control, as a result of the more compact semi-crystalline lamellae and homogenous electron distribution. Besides, all HMT-starches showed lowered breakdown and setback. This novel modified starch would be promising ingredients for modulating the viscoelasticity of healthy anti-staling staple foods.
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Calor , Triticum , Amilopectina/química , Almidón/química , Triticum/metabolismo , ViscosidadRESUMEN
Compared with three major cereals, underutilized cereals (UCs) are those with less use but having abundant bioactive components and better functionalities after proper processing. As a productive and energy-efficient technology, extrusion has been used for UC modification to improve its technological and nutritional quality. Extrusion could induce structural and quantitative changes in chemical components of UC flour, the degree of which is affected by extrusion intensity. Based on the predominant component (starch), functionalities of extruded underutilized cereal flour (EUCF) and potential mechanisms are reviewed. Considering bioactive compounds, it also summarizes the physiological functions of EUCF. EUCF incorporation could modulate the dough rheological behavior and starchy foods quality. Controlling extrusion intensity or incorporation level of EUCF is vital to achieve sensory-appealing and nutritious products. This paper gives comprehensive information of EUCF to promote its utilization in novel staple foods.
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Grano Comestible , Harina , Harina/análisis , Manipulación de Alimentos , Valor Nutritivo , AlmidónRESUMEN
OBJECTIVES: This study aims to investigate the pathogenic gene variant in a family with hypertrophic cardiomyopathy by using whole-exome sequencing and to explore the relationship between the gene variant and clinical phenotype. METHODS: Peripheral blood was collected from a family with hypertrophic cardiomyopathy, and deoxyribonucleic acid was extracted. The possible pathogenic genes were detected by whole-exome sequencing, and the variant was verified by Sanger sequencing. Functional change in the variant was predicted by bioinformatics software. Clinical data of the family members are analysed simultaneously. RESULTS: The proband carries a novel heterozygous nonsense variant of MYBPC3:c.2731G > T (p.E911X). The analysis of amino acid conservation suggests that the variation is highly conserved. The three-dimensional protein structure shows that the variant in MYBPC3 results in the incompleteness of the fibronectintype-III2 (p872-967) domain and deletion of Ig-like C2-type 6 (p971-1065) and fibronectin type-III 3 and Ig-like C2-type 7 (p1181-1274) domains, in which p1253-1268 is predicted to have a transmembrane helix structure. Clinical data indicate that the phenotypes of variant carriers with hypertrophic cardiomyopathy are diverse, suggesting the functional damages to the protein of MYBPC3. CONCLUSION: The phenotypes of variant carriers with hypertrophic cardiomyopathy caused by the novel variant in MYBPC3: c.2731G > T (p.E911X) exhibit variable severity and clinical manifestations. Whole-exome sequencing can be used to comprehensive screen hypertrophic cardiomyopathy genes and provide a strong basis for early screening and accurate diagnosis and treatment of hypertrophic cardiomyopathy in children.
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Cardiomiopatía Hipertrófica , Proteínas Portadoras , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/genética , Proteínas Portadoras/genética , Heterocigoto , Humanos , Mutación , Linaje , Fenotipo , Secuenciación del ExomaRESUMEN
Previous work has demonstrated that slightly acidic electrolyzed water (SAEW) can promote growth and nutrient enrichment of buckwheat sprouts. In this study, iTRAQ-based quantitative proteomic analysis of SAEW-induced buckwheat sprouts was conducted to explore its mechanism of action. The results showed that 11, 10 and 14 differentially expressed proteins (DEPs) related to energy metabolism, oxidative stress and flavonoid biosynthesis accumulated upwards and downwards, respectively, in SAEW-treated buckwheat. Bioinformatics analysis revealed 118 GO categories were in relation to molecular function. In the SAEW group, a total of 9 DEPs (5 up-regulated) were mapped to 10 significantly enriched KEGG pathways. SAEW induced flavonoid enrichment by modulating zymoproteins (e.g. phenylalanine ammonialyase and flavonol synthase) in phenylpropanoid biosynthesis pathway. qRT-PCR results had consistency with abundance levels of their corresponding proteins. These findings are likely to reveal the molecular mechanisms underlying the biochemical enrichment of buckwheat sprouts by SAEW.
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Fagopyrum , Electrólisis , Flavonoides , Proteómica , AguaRESUMEN
Cereals, one of the starch sources, have a tremendous and steady production worldwide. Starchy foods constitute the major part of daily calorie intake for humans. As a simple and green modification approach, heat-moisture treatment (HMT) could change the granular surface characteristics and size, crystalline and helical structure, as well as molecular organization of cereal starch. The changing degree is contingent on HMT parameters and botanical origin. Based on the hierarchical structure, this paper reviews functionalities of heat-moisture modified cereal starch (HMCS) reported in latest years. The functionality of HMCS could be affected by co-existing non-starch ingredients through non-covalent/covalent interactions, depolymerization or simply attachment/encapsulation. Besides, it summarizes the modulation of HMCS in dough rheology and final food products' quality. Selecting proper HMT conditions is crucial for achieving nutritious products with desirable sensory and storage quality. This review gives a systematic understanding about HMCS for the better utilization in food industry.
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Grano Comestible/química , Calor , Almidón/química , Manipulación de Alimentos , Calidad de los AlimentosRESUMEN
Starchy food is quiet common in human diet. Starch is often modified to be endowed with specific functionalities. Making flour by milling is almost inevitable during starch-based food processing. So milling modified starch, i.e. milling damaged starch (MDS) is discussed in this paper. Starch damage degree depends on both milling conditions and raw materials. In comparison with native starch, MDS has changed granular structure, disrupted crystalline region and molecular degradation. Hence, its functionalities are modified, including gelatinization, pasting property, digestion and water hydration properties. Furthermore, this review summarizes the effect of MDS on flour, dough and starchy food products. Controlling MDS at a moderate level is essential for the production of starch(y) foods with desirable quality. The measurement of MDS is also summarized. This paper provides a comprehensive knowledge of MDS in order to promote the flourishing of novel starch(y) foods production.
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Manipulación de Alimentos/métodos , Almidón/química , Harina/análisis , Calidad de los Alimentos , Gelatina/químicaRESUMEN
Ferric oxides and (oxy)hydroxides, although plentiful and low-cost, are rarely considered for oxygen evolution reaction (OER) owing to the too high spin state (eg filling ca. 2.0) suppressing the bonding strength with reaction intermediates. Now, a facile adsorption-oxidation strategy is used to anchor FeIII atomically on an ultrathin TiO2 nanobelt to synergistically lower the spin state (eg filling ca. 1.08) to enhance the adsorption with oxygen-containing intermediates and improve the electro-conductibility for lower ohmic loss. The electronic structure of the catalyst is predicted by DFT calculation and perfectly confirmed by experimental results. The catalyst exhibits superior performance for OER with overpotential 270â mV @10â mA cm-2 and 376â mV @100â mA cm-2 in alkaline solution, which is much better than IrO2 /C and RuO2 /C and is the best iron-based OER catalyst free of active metals such as Ni, Co, or precious metals.
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As a new class of metal-nitrogen-carbon (M-N-C) material with 3 D microstructure, zeolitic imidazolate frameworks (ZIFs) are used to synthesize highly active electrocatalysts for the oxygen reduction reaction, as substitutes for commercial Pt/C in anion exchange membrane fuel cells. However, to form an effective catalyst layer (CL), the relationship between the microstructure of the ZIF-derived catalyst and the fuel cell performance must be investigated. In this work, a hierarchically porous CL based on the carbon black (CB)-controlled synthesis of a Co-based ZIF (denoted as ZIF-CB-700) is constructed to optimize the triple-phase boundary (TPB) and mass transfer. The power density at 40 °C of ZIF-CB-700 (95.4â mW cm-2 ) as cathode catalyst is about 4 times higher than that of the catalyst synthesized in the absence of CB and is comparable to that of the commercial 60 % Pt/C catalyst (112.0â mW cm-2 ). Both online and offline measurements suggest that the morphology and microstructure of the CL is crucial to form an active TPB region, dominating the fuel cell performance rather than only the high catalyst activity.
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Context: Puerarin and triptolide are sometimes used together for the treatment of disease in Chinese clinics; however, the drug-drug interaction between puerarin and triptolide is still unknown. Objective: This study investigates the effects of puerarin on the pharmacokinetics of triptolide in rats and clarifies its main mechanism. Materials and methods: The pharmacokinetic profiles of oral administration of triptolide (1 mg/kg) in Sprague-Dawley rats with (test group, n = 6) or without pretreatment (control group, n = 6) with puerarin (100 mg/kg/day for seven days) were investigated. The effects of puerarin on the transport and metabolic stability of triptolide were also investigated using Caco-2 cell transwell model and rat liver microsomes. Results: The results showed that puerarin could significantly increase the peak plasma concentration (from 187.25 ± 15.36 to 219.67 ± 21.52 ng/mL), and decrease its oral clearance (from 4.92 ± 0.35 to 62.46 ± 3.75 ± 0.19 L/h/kg). The Caco-2 cell transwell experiments indicated that puerarin could decrease the efflux ratio of triptolide from 2.70 to 1.33, and the intrinsic clearance rate of triptolide was decreased by the pretreatment with puerarin (38.8 ± 4.7 vs. 32.9 ± 6.5 µL/min/mg protein). Discussion and conclusions: Puerarin could significantly change the pharmacokinetic profiles of triptolide in rats, and it might exert these effects through increasing the absorption of triptolide by inhibiting the activity of P-gp, or through inhibiting the metabolism of triptolide in rat liver. The results also showed that the dose of triptolide should be decreased when these drugs were co-administered.
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Antiinflamatorios/farmacología , Diterpenos/farmacocinética , Isoflavonas/farmacología , Fenantrenos/farmacocinética , Administración Oral , Animales , Células CACO-2 , Diterpenos/química , Interacciones Farmacológicas , Compuestos Epoxi/química , Compuestos Epoxi/farmacocinética , Humanos , Isoflavonas/química , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Fenantrenos/química , Ratas , Ratas Sprague-Dawley , Verapamilo/farmacologíaRESUMEN
Fe-doped transition metal (oxy)hydroxides are regarded as the most efficient oxygen evolution reaction (OER) electrocatalysts in alkaline conditions. The incorporation of Fe effectively enhances the OER activity of Co-/Ni-based materials, but the corresponding role of Fe in Co-based (oxy)hydroxide materials still remains unresolved. Herein, α-Co1-m Fem (OH)x is synthesized and systematically engineered to study the effect of Fe content on the morphology, crystalline structure, electronic structure, and OER activity. As the Fe content is changed, the basic crystalline phase of α-Co1-m Fem (OH)x is consistent whereas the micromorphology changes. Much smaller and thinner nanoplates with more edge/defect sites are fabricated because of increased Fe incorporation. When the Fe content is more than 0.1, twin nanoparticles emerge at the edge/defect sites of the sister nanoplate. Additionally, the OER activity of α-Co1-m Fem (OH)x against Fe content can be plotted as a volcano curve. These data thus support a hypothesis that the edge/defect sites in α-Co1-m Fem (OH)x are responsible for the OER performance. The incorporation of Fe leads to not only the accelerated intrinsic reactivity of each active site, which is attributed to the strong electronic interaction between Co and Fe but also changes the number of edge/defect sites.
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BACKGROUND: Obstructed defecation syndrome (ODS) is a widespread disease in the world. Rectocele is the most common cause of ODS in females. Multiple procedures have been performed to treat rectocele and no procedure has been accepted as the gold-standard procedure. Stapled transanal rectal resection (STARR) has been widely used. However, there are still some disadvantages in this procedure and its effectiveness in anterior wall repair is doubtful. Therefore, new procedures are expected to further improve the treatment of rectocele. AIM: To evaluate the efficacy and safety of a novel rectocele repair combining Khubchandani's procedure with stapled posterior rectal wall resection. METHODS: A cohort of 93 patients were recruited in our randomized clinical trial and were divided into two different groups in a randomized manner. Forty-two patients (group A) underwent Khubchandani's procedure with stapled posterior rectal wall resection and 51 patients (group B) underwent the STARR procedure. Follow-up was performed at 1, 3, 6, and 12 mo after the operation. Preoperative and postoperative ODS scores and depth of rectocele, postoperative complications, blood loss, and hospital stay of each patient were documented. All data were analyzed statistically to evaluate the efficiency and safety of our procedure. RESULTS: In group A, 42 patients underwent Khubchandani's procedure with stapled posterior rectal wall resection and 34 were followed until the final analysis. In group B, 51 patients underwent the STARR procedure and 37 were followed until the final analysis. Mean operative duration was 41.47 ± 6.43 min (group A) vs 39.24 ± 6.53 min (group B). Mean hospital stay was 3.15 ± 0.70 d (group A) vs 3.14 ± 0.54 d (group B). Mean blood loss was 10.91 ± 2.52 mL (group A) vs 10.14 ± 1.86 mL (group B). Mean ODS score in group A declined from 16.50 ± 2.06 before operation to 5.06 ± 1.07 one year after the operation, whereas in group B it was 17.11 ± 2.57 before operation and 6.03 ± 2.63 one year after the operation. Mean depth of rectocele decreased from 4.32 ± 0.96 cm (group A) vs 4.18 ± 0.95 cm (group B) preoperatively to 1.19 ± 0.43 cm (group A) vs 1.54 ± 0.82 cm (group B) one year after operation. No other serious complications, such as rectovaginal fistula, perianal sepsis, or deaths, were recorded. After 12 mo of follow-up, 30 patients' (30/34, 88.2%) final outcomes were judged as effective and 4 (4/34, 11.8%) as moderate in group A, whereas in group B, 30 (30/37, 81.1%) patients' outcomes were judged as effective, 5 (5/37, 13.5%) as moderate, and 2 (2/37, 5.4%) as poor. CONCLUSION: Khubchandani's procedure combined with stapled posterior rectal wall resection is an effective, feasible, and safe procedure with minor trauma to rectocele.
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Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Obstrucción Intestinal/cirugía , Rectocele/cirugía , Recto/cirugía , Grapado Quirúrgico/métodos , Adulto , Anciano , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Defecografía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias , Rectocele/complicaciones , Rectocele/diagnóstico por imagen , Recto/diagnóstico por imagen , Grapado Quirúrgico/efectos adversos , Resultado del Tratamiento , Adulto JovenRESUMEN
Hollow Silicalite-1 and ZSM-5 zeolites with hierarchical porous shells have been synthesized by using a dissolution-recrystallization method. The morphology, structure, and acidity of these zeolites supported Pt catalysts were characterized by XRD, FT-IR, MAS-SSNMR, FE-SEM, FE-TEM, N2-BET, XPS, NH3-TPD, and CO pulse chemisorption. Compared to the conventional ZSM-5 supported Pt catalyst, the special structure in hollow ZSM-5 zeolite significantly promotes the dispersion of metallic Pt and the synergistic effect between metal active sites and acid sites. These boost the catalytic activity, selectivity of guaiacol hydrodeoxygenation toward cycloalkanes and long-term stability over the Pt/hollow ZSM-5 catalyst combined with improved mass transfer of products and reactants derived from the hierarchical hollow porous structure. Moreover, the Pt/hollow ZSM-5 catalyst exhibits excellent low temperature catalytic activity to completely transform guaiacol into cycloalkanes with the cyclohexane selectivity of more than 93% at 220 °C, suggesting that hollow ZSM-5 zeolite is a promising support for upgrading of bio-oils.
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Direct methanol fuel cells (DMFCs) are promising power sources for automobiles and portable electronic devices. Its commercialization depends on the anodes with high activity, low Pt content, and especially high stability towards methanol oxidation. Herein, a self-supported Pt nanoflakes and amorphous Ni(OH)2 on nickel foam composite electrode (Pt-doped Ni(OH)2, Pt content: 1.5â¯wt%) with rich defects was fabricated via a facile and low cost galvanic deposition method. This composite anode exhibits enhanced activity and stability for methanol oxidation in alkaline media, which mainly come from the synergistic effects between Pt nanoflakes and amorphous Ni(OH)2 on Ni foam substrate and defect engineering. During a typical methanol oxidation process over Pt-doped Ni(OH)2: Pt nanoflakes act as the active sites; amorphous Ni(OH)2 promotes the poison removal; Ni foam provides high electric conductivity and large area; defects sites contribute to the enhanced activity and stability. This work suggests that this self-supported and defect-enriched Pt-doped Ni(OH)2 composite catalyst is an alternative to commercial Pt-based electrocatalyst for low temperature DMFCs.
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Oxygen evolution reaction (OER) plays a vital role in many energy conversion and storage processes including electrochemical water splitting for the production of hydrogen and carbon dioxide reduction to value-added chemicals. IrO2 and RuO2 , known as the state-of-the-art OER electrocatalysts, are severely limited by the high cost and low earth abundance of these noble metals. Developing noble-metal-free OER electrocatalysts with high performance has been in great demand. In this review, recent advances in the design and synthesis of noble-metal-free OER electrocatalysts including Ni, Co, Fe, Mn-based hydroxides/oxyhydroxides, oxides, chalcogenides, nitrides, phosphides, and metal-free compounds in alkaline, neutral as well as acidic electrolytes are summarized. Perspectives are also provided on the fabrication, evaluation of OER electrocatalysts and correlations between the structures of the electrocatalysts and their OER activities.
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Identification of active sites for oxygen evolution reaction (OER) plays a key role in the design and fabrication of high-performance cobalt-based electrocatalysts. Herein, we report the synthesis of two types of two-dimensional monometallic cobalt hydroxide nanoplates in aqueous solution for OER: α-Co(OH)2 with both Co2+Td and Co2+Oh sites and ß-Co(OH)2 with Co2+Oh sites. Electrochemical characterization reveals that α-Co(OH)2 is more active than ß-Co(OH)2 towards OER. The better activity can be attributed to the presence of Co2+Td sites in α-Co(OH)2, which are more active than Co2+Oh sites. Our finding clarifies the contribution of the two catalytic sites and helps future rational design of high-performance OER electrocatalysts.