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1.
Nanomaterials (Basel) ; 14(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38727403

RESUMEN

With the rapid development of anion exchange membrane technology and the availability of high-performance non-noble metal cathode catalysts in alkaline media, the commercialization of anion exchange membrane fuel cells has become feasible. Currently, anode materials for alkaline anion-exchange membrane fuel cells still rely on platinum-based catalysts, posing a challenge to the development of efficient low-Pt or Pt-free catalysts. Low-cost ruthenium-based anodes are being considered as alternatives to platinum. However, they still suffer from stability issues and strong oxophilicity. Here, we employ a metal-organic framework compound as a template to construct three-dimensional porous ruthenium-tungsten-zinc nanocages via solvothermal and high-temperature pyrolysis methods. The experimental results demonstrate that this porous ruthenium-tungsten-zinc nanocage with an electrochemical surface area of 116 m2 g-1 exhibits excellent catalytic activity for hydrogen oxidation reaction in alkali, with a kinetic density 1.82 times and a mass activity 8.18 times higher than that of commercial Pt/C, and a good catalytic stability, showing no obvious degradation of the current density after continuous operation for 10,000 s. These findings suggest that the developed catalyst holds promise for use in alkaline anion-exchange membrane fuel cells.

2.
Adv Sci (Weinh) ; : e2402240, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605604

RESUMEN

Single atomic catalysts have shown great potential in efficiently electro-converting O2 to H2O2 with high selectivity. However, the impact of coordination environment and introduction of extra metallic aggregates on catalytic performance still remains unclear. Herein, first a series of carbon-based catalysts with embedded coupling Ni single atomic sites and corresponding metallic nanoparticles at adjacent geometry is synthesized. Careful performance evaluation reveals NiSA/NiNP-NSCNT catalyst with precisely controlled active centers of synergetic adjacent Ni-N4S single sites and crystalline Ni nanoparticles exhibits a high H2O2 selectivity over 92.7% within a wide potential range (maximum selectivity can reach 98.4%). Theoretical studies uncover that spatially coupling single atomic NiN4S sites with metallic Ni aggregates in close proximity can optimize the adsorption behavior of key intermediates *OOH to achieve a nearly ideal binding strength, which thus affording a kinetically favorable pathway for H2O2 production. This strategy of manipulating the interaction between single atoms and metallic aggregates offers a promising direction to design new high-performance catalysts for practical H2O2 electrosynthesis.

3.
Sci Adv ; 9(27): eadh2885, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37406120

RESUMEN

Large-scale deployment of proton exchange membrane (PEM) water electrolyzers has to overcome a cost barrier resulting from the exclusive adoption of platinum group metal (PGM) catalysts. Ideally, carbon-supported platinum used at cathode should be replaced with PGM-free catalysts, but they often undergo insufficient activity and stability subjecting to corrosive acidic conditions. Inspired by marcasite existed under acidic environments in nature, we report a sulfur doping-driven structural transformation from pyrite-type cobalt diselenide to pure marcasite counterpart. The resultant catalyst drives hydrogen evolution reaction with low overpotential of 67 millivolts at 10 milliamperes per square centimeter and exhibits no degradation after 1000 hours of testing in acid. Moreover, a PEM electrolyzer with this catalyst as cathode runs stably over 410 hours at 1 ampere per square centimeter and 60°C. The marked properties arise from sulfur doping that not only triggers formation of acid-resistant marcasite structure but also tailors electronic states (e.g., work function) for improved hydrogen diffusion and electrocatalysis.

4.
Exp Ther Med ; 26(1): 357, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37324516

RESUMEN

From July 2020 to March 2022, 3 patients with papillary thyroid cancer (PTC) and microgenia underwent transoral endoscopic thyroid surgery via a vestibular approach or a endoscopic lateral neck dissection via the breast and transoral approaches with chin silastic augmentation genioplasty performed concurrently. Image documentation, patient satisfaction, complications and other factors such as demographics and clinicopathologic details were recorded. None of the patients developed major complications and there were no complications such as infection or displacement of the implant. All patients were satisfied with the cosmetic outcomes. Despite the study being limited to these 3 selected patients with PTC and microgenia, the follow-up to our initial description of the new technique established its safety and efficacy.

5.
J Am Chem Soc ; 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37021910

RESUMEN

Electrocatalytic carbon dioxide reduction (CO2R) in neutral electrolytes can mitigate the energy and carbon losses caused by carbonate formation but often experiences unsatisfied multicarbon selectivity and reaction rates because of the kinetic limitation to the critical carbon monoxide (CO)-CO coupling step. Here, we describe that a dual-phase copper-based catalyst with abundant Cu(I) sites at the amorphous-nanocrystalline interfaces, which is electrochemically robust in reducing environments, can enhance chloride-specific adsorption and consequently mediate local *CO coverage for improved CO-CO coupling kinetics. Using this catalyst design strategy, we demonstrate efficient multicarbon production from CO2R in a neutral potassium chloride electrolyte (pH ∼6.6) with a high Faradaic efficiency of 81% and a partial current density of 322 milliamperes per square centimeter. This catalyst is stable after 45 h of operation at current densities relevant to commercial CO2 electrolysis (300 mA per square centimeter).

6.
Nat Commun ; 14(1): 2306, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085504

RESUMEN

Finding highly efficient hydrogen evolution reaction (HER) catalysts is pertinent to the ultimate goal of transformation into a net-zero carbon emission society. The design principles for such HER catalysts lie in the well-known structure-property relationship, which guides the synthesis procedure that creates catalyst with target properties such as catalytic activity. Here we report a general strategy to synthesize 10 kinds of single-atom-doped CoSe2-DETA (DETA = diethylenetriamine) nanobelts. By systematically analyzing these products, we demonstrate a volcano-shape correlation between HER activity and Co atomic configuration (ratio of Co-N bonds to Co-Se bonds). Specifically, Pb-CoSe2-DETA catalyst reaches current density of 10 mA cm-2 at 74 mV in acidic electrolyte (0.5 M H2SO4, pH ~0.35). This striking catalytic performance can be attributed to its optimized Co atomic configuration induced by single-atom doping.

7.
Adv Mater ; 34(43): e2205414, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36042002

RESUMEN

Electrochemical generation of hydrogen peroxide (H2 O2 ) by two-electron oxygen reduction offers a green method to mitigate the current dependence on the energy-intensive anthraquinone process, promising its on-site applications. Unfortunately, in alkaline environments, H2 O2 is not stable and undergoes rapid decomposition. Making H2 O2 in acidic electrolytes can prevent its decomposition, but choices of active, stable, and selective electrocatalysts are significantly limited. Here, the selective and efficient two-electron reduction of oxygen toward H2 O2 in acid by a composite catalyst that is composed of black phosphorus (BP) nailed chemically on the metallic cobalt diselenide (CoSe2 ) surface is reported. It is found that this catalyst exhibits a 91% Faradic efficiency for H2 O2 product at an overpotential of 300 mV. Moreover, it can mediate oxygen to H2 O2 with a high production rate of ≈1530 mg L-1 h-1 cm-2 in a flow-cell reactor. Spectroscopic and computational studies together uncover a BP-induced surface charge redistribution in CoSe2 , which leads to a favorable surface electronic structure that weakens the HOO* adsorption, thus enhancing the kinetics toward H2 O2 formation.

8.
Retina ; 42(11): 2051-2058, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35839487

RESUMEN

PURPOSE: To investigate the outcomes of macular buckling combined with vitrectomy and inverted internal limiting membrane flap technique for highly myopic full-thickness macular hole (FTMH) with macular retinoschisis. METHODS: Twenty-six eyes of 26 consecutive patients were retrospectively included. Twelve eyes underwent macular buckling alone (buckling group). Fourteen eyes underwent macular buckling and vitrectomy with an inverted internal limiting membrane flap technique (combination group). Patients were followed for at least 9 months. Rates of FTMH closure and macular retinoschisis resolution, best-corrected visual acuity gained at the final visit were evaluated. RESULTS: The mean follow-up time was 13.00 ± 3.16 months. FTMH closed in six eyes (50%) of the buckling group and 13 eyes (92.86%) of the combination group ( P = 0.026) at the final visit. The macular retinoschisis resolution rate was close between two groups (100% vs. 92.86%; P = 1.000). Both groups achieved significant improvement in best-corrected visual acuity (10.42 ± 17.25 and 16.36 ± 10.39 Early Treatment Diabetic Retinopathy Study letters; P = 0.014 and P < 0.001). The combination group achieved slightly more best-corrected visual acuity improvement, but the difference fell short of significance ( P =0.312). CONCLUSION: Combination of macular buckling and vitrectomy with the inverted internal limiting membrane flap technique could achieve a high FTMH closure rate and significant best-corrected visual acuity improvement in FTMH with macular retinoschisis.


Asunto(s)
Degeneración Macular , Miopía Degenerativa , Miopía , Desprendimiento de Retina , Perforaciones de la Retina , Retinosquisis , Humanos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Vitrectomía/métodos , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Retinosquisis/diagnóstico , Retinosquisis/cirugía , Estudios Retrospectivos , Agudeza Visual , Miopía/cirugía , Degeneración Macular/cirugía , Membrana Basal/cirugía , Tomografía de Coherencia Óptica
9.
Angew Chem Int Ed Engl ; 60(52): 26922-26931, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34553478

RESUMEN

Electrosynthesis of hydrogen peroxide (H2 O2 ) in the acidic environment could largely prevent its decomposition to water, but efficient catalysts that constitute entirely earth-abundant elements are lacking. Here we report the experimental demonstration of narrowing the interlayer gap of metallic cobalt diselenide (CoSe2 ), which creates high-performance catalyst to selectively drive two-electron oxygen reduction toward H2 O2 in an acidic electrolyte. The enhancement of the interlayer coupling between CoSe2 atomic layers offers a favorable surface electronic structure that weakens the critical *OOH adsorption, promoting the energetics for H2 O2 production. Consequently, on the strongly coupled CoSe2 catalyst, we achieved Faradaic efficiency of 96.7 %, current density of 50.04 milliamperes per square centimeter, and product rate of 30.60 mg cm-2 h-1 . Moreover, this catalyst shows no sign of degradation when operating at -63 milliamperes per square centimeter over 100 hours.

10.
Int J Mol Med ; 47(1): 151-160, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33416109

RESUMEN

As a specific microvascular complication of diabetes, diabetic retinopathy (DR) causes severe visual impairment in patients with diabetes. The expression of microRNA­126 (miRNA/miR­126) has previously been found to be significantly decreased in the serum of patients with DR. In the present study, the functions of miR­126 and its mechanisms of action in experimental diabetic retinopathy were examined in rats with streptozotocin (STZ)­induced diabetes and in high glucose (HG)­induced human retinal capillary endothelial cells (HRCECs). In vivo, diabetic rat models were established and the rats were intravitreally injected with lentivirus expressing rno­miR­126 (lenti­miR­126) or negative control (lenti­NC). RT­qPCR was used to determine the miR­126 level in the serum and retina. Paraffin sections and retinal vasculature were used to determine the extent of retinopathy. The protein content of vascular endothelial growth factor (VEGF) and pigment epithelium­derived factor (PEDF) in the retina was used as an auxiliary measurement of retinopathy. Western blot analysis and immunofluorescence staining were used to measure the expression of polo­like kinase 4 (PLK4) in rat retinal tissue. In vitro, the cells were transfected with miR­126 inhibitor or mimic and treated with the PLK4 inhibitor, CFI­400945 fumarate. RT­qPCR and western blot analysis were used to detect the miR­126 level and PLK4 expression. Cell proliferation and migration were measured by EdU and Transwell assays. The diabetic rats were found to exhibit downregulated serum and retinal miR­126 levels compared with the non­diabetic rats. The intravitreal delivery of miR­126 alleviated retinopathy and reduced the diabetes­induced upregulation of PLK4 in retinal tissues. Luciferase reporter assays confirmed that PLK4 mRNA was the target of miR­126. In HG­induced HRCECs, transfection with miR­126 mimic increased the miR­126 level, whereas it downregulated that of its downstream target, PLK4, which was opposite to the effects exerted by the miR­126 inhibitor. Furthermore, miR­126 mimic and CFI­400945 fumarate reduced the HG­induced upregulation of PLK4 expression, as well as cell proliferation and migration. On the whole, the findings of the present study demonstrate that miR­126 reduces experimental diabetic retinopathy and suppresses endothelial cell proliferation and migration by targeting PLK4. Thus, miR­126 and CFI­400945 fumarate may be therapeutic targets for DR.


Asunto(s)
Movimiento Celular , Proliferación Celular , Diabetes Mellitus Experimental/metabolismo , Retinopatía Diabética/metabolismo , Células Endoteliales/metabolismo , MicroARNs/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Diabetes Mellitus Experimental/patología , Retinopatía Diabética/patología , Células Endoteliales/patología , Ratas
11.
Angew Chem Int Ed Engl ; 60(12): 6553-6560, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33438257

RESUMEN

Although the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag2 Se on CoSe2 nanobelts relied on diffusion-driven instability. The resultant Turing-type Ag2 Se-CoSe2 material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.5 % anodic energy efficiency. Electrochemical measurements show that the intrinsic OER activity correlates linearly with the length of Ag2 Se-CoSe2 interfaces, determining that such Turing-type interfaces are more active sites for OER. Combing X-ray absorption and computational simulations, we ascribe the excellent OER performance to the optimized adsorption energies for critical oxygen-containing intermediates at the unconventional interfaces.

12.
BMC Ophthalmol ; 20(1): 297, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32689970

RESUMEN

BACKGROUND: To investigate the expression and significance of mechanistic target of rapamycin complex 1(mTORC1) in diabetic retinopathy (DR), and to find new targets and new methods for the treatment of DR. METHODS: A DR rat model was prepared by general feeding combined with intraperitoneal injection of 10% streptozotocin (60 mg/kg). The rats were randomly divided into a control group (NDM group) and a diabetes group (DM group). Three months later, the degrees of retinopathy was determined using hematoxylin and eosin staining, and the levels of p-S6, VEGF, and PEDF proteins were detected by immunohistochemistry and western blotting. Human retinal capillary endothelial cells (HRCECs) were cultured in high glucose (HG) conditions, then treated with rapamycin or transfected with siTSC1.The protein levels of p-S6 were assessed by western blotting. The 5-ethynyl-2'-deoxyuridine assay was used to detect cell proliferation, and the Transwell assay was used to detect cell migration. RESULTS: A DM rat model was successfully developed. The expressions of p-S6 and VEGF proteins were significantly increased in the DM group (p < 0.05), and the expression of PEDF protein was significantly decreased compared with the NDM group (p < 0.05). In vitro, the p-S6 protein, as well as cell proliferation and migration, in HG induced HRCECs were increased (p < 0.05) compared with the control (normal glucose) group (p < 0.05). After transfection with siTSC1 to activate mTORC1, the expression of p-S6, as well as cell proliferation and migration, were increased. In contrast, rapamycin decreased p-S6 expression, as well as proliferation and migration, in HG induced HRCECs compared to the control group (p < 0.05). CONCLUSION: mTORC1 plays an important role in DR. After activation, mTORC1 induced expression of the p-S6 protein, regulated the expressions of VEGF and PEDF proteins, and changed the proliferation and migration of endothelial cells. The mTORC1 can therefore be used as a new target,as well as in the treatment of DR.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Serpinas , Animales , Células Endoteliales , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratas , Retina
13.
J Am Chem Soc ; 142(13): 6400-6408, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32176485

RESUMEN

Selective and efficient catalytic conversion of carbon dioxide (CO2) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO2 reduction to oxygenates and hydrocarbons (e.g., C2+ compounds) is the difficulty of coupling carbon-carbon bonds efficiently. Copper in the +1 oxidation state has been thought to be active for catalyzing C2+ formation, whereas it is prone to being reduced to Cu0 at cathodic potentials. Here we report that catalysts with nanocavities can confine carbon intermediates formed in situ, which in turn covers the local catalyst surface and thereby stabilizes Cu+ species. Experimental measurements on multihollow cuprous oxide catalyst exhibit a C2+ Faradaic efficiency of 75.2 ± 2.7% at a C2+ partial current density of 267 ± 13 mA cm-2 and a large C2+-to-C1 ratio of ∼7.2. Operando Raman spectra, in conjunction with X-ray absorption studies, confirm that Cu+ species in the as-designed catalyst are well retained during CO2 reduction, which leads to the marked C2+ selectivity at a large conversion rate.

14.
Angew Chem Int Ed Engl ; 59(22): 8706-8712, 2020 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-31884699

RESUMEN

A considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO2 to CO2 .- or other intermediates, which often requires precious-metal catalysts, high overpotentials, and/or electrolyte additives (e.g., ionic liquids). We report a microwave heating strategy for synthesizing a transition-metal chalcogenide nanostructure that efficiently catalyzes CO2 electroreduction to carbon monoxide (CO). We found that the cadmium sulfide (CdS) nanoneedle arrays exhibit an unprecedented current density of 212 mA cm-2 with 95.5±4.0 % CO Faraday efficiency at -1.2 V versus a reversible hydrogen electrode (RHE; without iR correction). Experimental and computational studies show that the high-curvature CdS nanostructured catalyst has a pronounced proximity effect which gives rise to large electric field enhancement, which can concentrate alkali-metal cations resulting in the enhanced CO2 electroreduction efficiency.

15.
Nat Commun ; 10(1): 5338, 2019 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-31767845

RESUMEN

Many platinum group metal-free inorganic catalysts have demonstrated high intrinsic activity for diverse important electrode reactions, but their practical use often suffers from undesirable structural degradation and hence poor stability, especially in acidic media. We report here an alkali-heating synthesis to achieve phase-mixed cobalt diselenide material with nearly homogeneous distribution of cubic and orthorhombic phases. Using water electroreduction as a model reaction, we observe that the phase-mixed cobalt diselenide reaches the current density of 10 milliamperes per square centimeter at overpotential of mere 124 millivolts in acidic electrolyte. The catalyst shows no sign of deactivation after more than 400 h of continuous operation and the polarization curve is well retained after 50,000 potential cycles. Experimental and computational investigations uncover a boosted covalency between Co and Se atoms resulting from the phase mixture, which substantially enhances the lattice robustness and thereby the material stability. The findings provide promising design strategy for long-lived catalysts in acid through crystal phase engineering.

16.
Research (Wash D C) ; 2019: 8078549, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31549084

RESUMEN

Material interfaces permit electron transfer that modulates the electronic structure and surface properties of catalysts, leading to radically enhanced rates for many important reactions. Unlike conventional thoughts, the nanoscale interfacial interactions have been recently envisioned to be able to affect the reactivity of catalysts far from the interface. However, demonstration of such unlocalized alterations in existing interfacial materials is rare, impeding the development of new catalysts. We report the observation of unprecedented long-range activation of polydymite Ni3S4 nanorods through the interfacial interaction created by PdSx nanodots (dot-on-rod structure) for high-performance water catalytic electroreduction. Experimental results show that this local interaction can activate Ni3S4 rods with length even up to 25 nanometers due to the tailored surface electronic structure. We anticipate that the long-range effect described here may be also applicable to other interfacial material systems, which will aid the development of newly advanced catalysts for modern energy devices.

17.
J Diabetes Complications ; 33(10): 107383, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31371129

RESUMEN

AIM: To study the factors protecting against diabetic retinopathy (DR) in patients with over a decade-long history of type 2 diabetes mellitus. METHODS: A total of 490 patients with type 2 diabetes mellitus lasting for ≥10 years were divided into DR and no diabetic retinopathy (no DR) groups. Their basic information was collected, including age, sex, and duration of diabetes mellitus, as well as pertinent laboratory data. Potential correlations between these factors and DR were evaluated using multivariate analysis. RESULTS: Overall, 208 patients met the diagnostic criteria for DR. Multivariate logistic regression was used to evaluate factors with P < 0.10 after univariate analysis. Age, total bilirubin, and total cholesterol were found to be protective factors against DR. Presence of diabetic kidney disease and diabetic peripheral neuropathy, duration of diabetes mellitus, apolipoprotein B, blood urea nitrogen, and prothrombin time were found to be risk factors for DR. CONCLUSIONS: We conclude that total cholesterol is a protective factor against DR. Specifically, it was confirmed that high levels of total cholesterol reduce the risk of DR. These findings may provide a basis for new diet and lifestyle guidelines for patients with diabetes mellitus.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Bilirrubina/sangre , Colesterol/sangre , Diabetes Mellitus Tipo 2/sangre , Retinopatía Diabética/sangre , Retinopatía Diabética/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Protectores , Factores de Riesgo , Factores de Tiempo
18.
ChemSusChem ; 12(16): 3747-3752, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31295386

RESUMEN

Bio-inspired synthesis of functional materials with highly ordered structure and tunable properties is of particular interest, but efficient approaches that allow the access of these materials are still limited. A method has been developed for the preparation of hematite particles by using xonotlite nanowires (XNWs) as growth modifiers. The concentration of the XNWs has a profound effect on the final morphology of the products, whereas the concentration of the iron(III) ions can control the size of the hematite particles. The underlying mechanism of the bio-inspired XNW-modified mineralization process has been proposed. The obtained hematite particles exhibit good catalytic performance in the oxygen evolution reaction (OER), affording a current density of 10 mA cm-2 with an overpotential of 370 mV, a small Tafel slope of 65 mV dec-1 , and good stability in alkaline electrolyte. This strategy for preparing functional materials by using nanowires as the growth modifiers has great potential for future application in the construction of various materials with hierarchical structures.

19.
J Am Chem Soc ; 141(18): 7537-7543, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31017425

RESUMEN

The design of highly efficient non-noble-metal electrocatalysts for large-scale hydrogen production remains an ongoing challenge. We report here a Ni2P nanoarray catalyst grown on a commercial Ni foam substrate, which demonstrates an outstanding electrocatalytic activity and stability in basic electrolyte. The high catalytic activity can be attributed to the favorable electron transfer, superior intrinsic activity, and the intimate connection between the nanoarrays and their substrate. Moreover, the unique "superaerophobic" surface feature of the Ni2P nanoarrays enables a remarkable capability to withstand internal and external forces and release the in situ generated H2 bubbles in a timely manner at large current densities (such as >1000 mA cm-2) where the hydrogen evolution becomes vigorous. Our results highlight that an aerophobic structure is essential to catalyze gas evolution for large-scale practical applications.

20.
Angew Chem Int Ed Engl ; 57(47): 15445-15449, 2018 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-30281194

RESUMEN

Transition-metal phosphides have stimulated great interest as catalysts to drive the hydrogen evolution reaction (HER), but their use as bifunctional catalytic electrodes that enable efficient neutral-pH water splitting has rarely been achieved. Herein, we report the synthesis of ternary Ni0.1 Co0.9 P porous nanosheets onto conductive carbon fiber paper that can efficiently and robustly catalyze both the HER and water oxidation in 1 m phosphate buffer (PBS; pH 7) electrolyte under ambient conditions. A water electrolysis cell comprising the Ni0.1 Co0.9 P electrodes demonstrates remarkable activity and stability for the electrochemical splitting of neutral-pH water. We attribute this performance to the new ternary Ni0.1 Co0.9 P structure with porous surfaces and favorable electronic states resulting from the synergistic interplay between nickel and cobalt. Ternary metal phosphides hold promise as efficient and low-cost catalysts for neutral-pH water splitting devices.

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