- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
A Highly Efficient and Durable Water Splitting System: Platinum Sub-Nanoclusters Functionalized Nickel Iron Layered Double Hydroxides as the Cathode and Hierarchical Nickel Iron Selenides as the Anode
摘要： Developing cost-efficient and effective catalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remains a great challenge for the applications of high-efficiency water electrolyzers. In this work, we design a highly efficient and durable water splitting system in an alkaline solution, of which the platinum (Pt) sub-nanoclusters (average size: 0.59 nm) functionalized nickel iron layered double hydroxide nanosheets on carbon fiber cloth (Pt-NiFe LDH/CC) serve as the cathode and the hierarchical (Ni0.77Fe0.23)Se2 nanosheets on CC ((Ni0.77Fe0.23)Se2/CC) act as the anode. For the HER, the three-dimensional (3D) Pt-NiFe LDH/CC electrode with an ultralow Pt content (1.56 wt%) drives a current density of 10 mA cm-2 under an ultralow overpotential of 28 mV. For the OER, the edge-rich (Ni0.77Fe0.23)Se2/CC electrode displays a current density of 10 mA cm?2 under a small overpotential of 228 mV, and the Tafel slope is as low as 69 mV dec?1. More importantly, the assembled Pt-NiFe LDH/CC || (Ni0.77Fe0.23)Se2/CC water splitting electrolyzer exhibits a high current density of 30 mA cm?2 at a low cell voltage of 1.57 V, which is superior than that of electrolyzer assembled by the commercial 20 wt% Pt/C and RuO2 electrodes (30 mA cm?2 at 1.62 V). Additionally, the Pt-NiFe LDH/CC || (Ni0.77Fe0.23)Se2/CC electrolyzer displays excellent stability over 40 hours even at a high current density of 50 mA cm?2, which shows a great potential in the practical applications of full water splitting.
关键词： Hydrogen Evolution Reaction,Platinum Sub-Nanoclusters,Oxygen Evolution Reaction,NiFe Layered Double Hydroxide,Porous NiFe Selenide
更新于2025-09-19 17:15:36
-
Smart yolk/Shell ZIF-67@POM Hybrids as Efficient Electrocatalysts for the Oxygen Evolution Reaction
摘要： The purpose of this research is to develop an effective and inexpensive oxygen evolution reaction (OER) electrocatalysts to achieve high-efficiency water decomposition. Herein, Keggin-type polyoxometalate (POM) nanoparticles coated with zeolitic imidazolate framework (ZIF-67) are successfully synthesized by facile methods. An efficient ZIF-67@POM catalyst with yolk/shell structure is reported. The POM nanomaterials are uniformly dispersed in the surface of ZIF-67. This unique yolk/shell structure with potential synergistic interaction between POM and ZIF-67 result in superior electrocatalytic activity in OER. When the current density is 10 mA cm-2, the overpotential is only 287 mV, and the Tafel slope is 58 mV per decade. Moreover, the as-prepared yolk/shell ZIF-67@POM catalysts exhibit excellent cycling stability, high surface area, abundant surface active sites and high diffusion efficiency comparable to the traditional noble-metal-free OER electrocatalyst.
关键词： polyoxometalate,metal-organic framework,electrocatalysis,oxygen evolution reaction
更新于2025-09-19 17:15:36
-
Electrosynthesis of Copper phosphide thin films for efficient water oxidation
摘要： A copper phosphide (Cu3P) thin film is synthesized on a Ni foam using a one-step electrodeposition method at room temperature and annealed at 300 °C in Ar atmosphere. The Cu3P film is amorphous and has a flat morphology with surface voids. It works as an electrocatalyst for water oxidation in an alkaline 1M KOH electrolyte. It exhibits excellent catalytic oxygen evolution reaction with an overpotential of 310 mV, Tafel slope of 88 mV/dec, and good stability over 20 h of operation at 10 mA/cm2. The excellent OER performance is due to its large electrochemically active surface area and low charge transfer resistance at the catalyst-electrolyte interface after the annealing.
关键词： annealing effect,Copper phosphide,oxygen evolution reaction,electrodeposition
更新于2025-09-19 17:15:36
-
Ultrafast fabrication of Cu oxide micro/nano-structures via laser ablation to promote oxygen evolution reaction
摘要： Despite the tremendous efforts on the preparation of efficient oxygen evolution reaction (OER) electrocatalysts, it is still a challenge to fabricate stable OER electrocatalysts with good performance on a large scale in a simple, fast, green, and environment-friendly way. Herein, we report a simple way via femtosecond laser ablation to fabricate Cu oxide micro/nano-structures on Cu foams by fine-tuning of the laser parameters. The present method is ultrafast, non-contact, high efficiency, easy control, sustainable, and environment-friendly. The fabricated catalysts exhibit remarkable OER activity and excellent durability in 1 M KOH.
关键词： Water splitting,Laser ablation,Metal oxides,Oxygen evolution reaction
更新于2025-09-16 10:30:52
-
Copper Tungstate (CuWO4) Nanoflakes Coupled with Cobalt Phosphate (Co-Pi) for Effective Photoelectrochemical Water Splitting
摘要： Photoelectrochemical (PEC) water splitting provides us a green way to convert and utilize solar energy. In this work, Co-Pi was electrochemically deposited onto CuWO4 nanoflakes (NFs) via a cyclic voltammetry (CV) method to enhance the photocatalytic performance of CuWO4 toward PEC water splitting. The results demonstrated that the photocurrent density as well as the charge-transfer efficiency was improved within the entire potential range. Besides, the CuWO4/Co-Pi exhibited an enhanced stability over the bare CuWO4 in the phosphate buffer solution (pH 7) and an extremely high Faradaic efficiency (ca. 96%). Our work reveals that combination of CuWO4 with Co-Pi is a feasible way to further enhance the performance of CuWO4 photoanode toward PEC OER.
关键词： Photoelectrochemical water splitting,oxygen evolution reaction,copper tungstate,electrochemical cocatalyst,cobalt phosphate
更新于2025-09-16 10:30:52
-
Charge Transfer Engineering via Multiple Heteroatom Doping in Dual Carbon-Coupled Cobalt Phosphides for Highly Efficient Overall Water Splitting
摘要： The exploration of non-noble-metal bifunctional electrocatalysts with high activity and stability for overall water splitting is crucial, but remains challenging for hydrogen fuel production. Herein, tuning of the charge transfer ability and catalytic performance of zeolitic imidazolate framework-derived porous carbon/reduced graphene oxide-coupled CoP composites (CoP@C@rGO) was achieved by incorporating multiple heteroatoms. The combined experimental investigation and density functional theory calculations revealed that the electronic interaction within the composites caused by B, N, and S tri-doped heteroatoms effectively induced interfacial charge transfer, which improved the active site accessibility and reduced the energy barriers of the evolution reaction; water splitting intermediates. From the synergetic effects of the components, the overall water splitting electrolyzer assembled using the newly prepared B,N,S-CoP@C@rGO catalyst required only 1.50 V to drive a current density of 10 mA cm–2, which is superior to the commercial Pt/C and IrO2/C couple (1.56 V).
关键词： hydrogen evolution reaction,oxygen evolution reaction,multiple doping,overall water splitting,charge transfer
更新于2025-09-12 10:27:22
-
Pulsed laser deposited Cr-doped CoFe2O4 thin film as highly efficient oxygen evolution reaction electrode
摘要： Traditional powder OER catalysts have many disadvantages such as the extremely complicated electrode preparation process. Herein, squama-like Co0.95Cr0.05Fe2O4 thin film electrode is directly deposited on flexible Ni foam substrate by a novel method of pulsed laser deposition. Cr doping leads to the electrode highly effective for OER, and the current density is about 2.1 times of that compared with undoped CoFe2O4 thin film at 1.8 V. The Co0.95Cr0.05Fe2O4 thin film exhibits an overpotential of 293.3 mV at 10 mA/cm2 as well as extraordinary stability, which is far better than that of CoFe2O4 thin film and no-load Ni foam.
关键词： Thin films,Pulsed laser deposition,Electron microscopy,Oxygen evolution reaction
更新于2025-09-12 10:27:22
-
Structure–Activity/Stability Correlations from the Electrochemical Dynamic Responses of Titanium Anode Coatings Formed of Ordered TiO <sub/>2</sub> @RuO <sub/>2</sub> Microspheres
摘要： Spherical TiO2/RuO2 particles were synthesized by ultrasonic spray pyrolysis (USP) at 200 and 800?C. The activity for the oxygen and chlorine evolution reactions (OER and CER, respectively) and the dynamic responses from electrochemical impedance spectroscopy (EIS) of the USP powders, as well as of the corresponding coatings on Ti, were analyzed and are discussed. The loss of coating activity is discussed with respect to the differences in the EIS and cyclic voltammetry responses of the coatings in their active and inactive states. The 800?C-USP sample was found to be more active than the 200?C-USP sample for both the CER and the OER, whereas the stability of the former was considerably lower. The correlation between the structure, composition and morphology of the powder and the coating with the registered electrochemical properties is discussed. The EIS analysis of the coating resistance distributions induced by the thermal treatment of the powder indicated a complex combination of the pore resistance and the pseudocapacitive charge transfer resistance. An additional coating resistance, due to loose grain boundaries, was introduced into the coatings in their active and inactive state. The EIS analysis indicated the changes in TiO2-enriched core/RuO2-enriched shell structure, caused by the USP temperature.
关键词： TiO2/RuO2,cyclic voltammetry,electrochemical impedance spectroscopy,oxygen evolution reaction,chlorine evolution reaction,ultrasonic spray pyrolysis,coating stability
更新于2025-09-11 14:15:04
-
Laser fragmentation induced defect‐rich cobalt oxide nanoparticles for electrochemical oxygen evolution reaction
摘要： Sub-5 nm cobalt oxide nanoparticles were produced in a water flowing system by pulsed laser fragmentation in liquid (PLFL). Particle fragmentation from 8 nm to 4 nm was observed and proposed to be induced by the oxidation process in water where oxidative species were present and the local temperature was rapidly elevated under laser irradiation. Significantly higher surface area, crystal phase transformation and formation of structural defects (Co2+ defects and oxygen vacancies) through the PLFL process were evidenced by a detailed structural characterization using nitrogen physisorption, electron microscopy, synchrotron X-ray diffraction and X-ray photoelectron spectroscopy. When employed as electrocatalysts for the oxygen evolution reaction under alkaline conditions, the fragmented cobalt oxides exhibited superior catalytic activity over pristine and nanocasted cobalt oxides, with delivering a current density of 10 mA/cm2 at 369 mV and a Tafel slope of 46 mV/dec, which is attributed to: (i) a larger exposed active surface area, (ii) formation of defects and iii) an increased charge transfer rate. The study provides an effective approach to engineer cobalt oxide nanostructure in a water flowing system, which shows great potential for sustainable production of active cobalt catalysts.
关键词： structural defects,cobalt oxide,nanostructure,Oxygen evolution reaction,laser fragmentation
更新于2025-09-11 14:15:04
-
Synthesis and improved photoluminescence of hexagonal crystals of Li <sub/>2</sub> ZrF <sub/>6</sub> :Mn <sup>4+</sup> for warm WLED application
摘要： Engineering compositions, structures, and defects can endow nanomaterials with optimized catalytic properties. Here, we report that cobalt oxide (CoOx) ultrathin nanosheets (UTNS, ～1.6 nm thick) with a large number of oxygen defects and mixed cobalt valences can be obtained through a facile one-step hydrothermal protocol. The large number of oxygen defects make the ultrathin CoOx nanosheet a superior OER catalyst with low overpotentials of 315 and 365 mV at current densities of 50 and 200 mA cm?2, respectively. The stable framework-like architectures of the UTNS further ensure their high OER activity and durability. Our method represents a facile one-step preparation of CoOx nanostructures with tunable compositions, morphologies, and defects, and thus promotes OER properties. This strategy may find its wider applicability in designing active, robust, and easy-to-obtain catalysts for OER and other electrocatalytic systems.
关键词： ultrathin nanosheets,oxygen evolution reaction,electrocatalysis,hydrothermal synthesis,cobalt oxide
更新于2025-09-11 14:15:04