查找使用阿拉丁产品的科研文献

High adaptability and stability FeCo2O4/diatomite composite for efficient peroxymonosulfate activation: Performance, water matrix impact, and mechanism

Peng Xu,Xiang Li,Rui Wei,Chunyan Yang,Tianyao Shen,Peng Wang,Guangshan Zhang

The adaptability and stability of catalysts guarantee efficient catalytic performance. Hence, we fabricated FeCo 2 O 4 /diatomite for efficient peroxymonosulfate (PMS) activation. Distinct from stacked FeCo 2 O 4 , FeCo 2 O 4 /diatomite possessed a 1.2-fold larger specific surface area (94.84 m 2 g −1 ), achieving 100% ATZ removal within 10 min at 0.2 g L −1 PMS and 0.1 g L −1 FeCo 2 O 4 /diatomite. The system could adapt to a broad pH range (3–11) and complex water matrices, efficiently removing multiple contaminants. High removal performance (>92%) and mineralization (>57%) were maintained after six cycles with minimal leached Co (0.10 mg L −1 ). The conversion between ≡Fe(III)/≡Fe(II) and ≡Co(III)/≡Co(II) could trigger PMS persistently, producing abundant active species, in which SO 4 •− was dominant. Then, intermediates and degradation pathways were proposed based on DFT calculations and ESI-QTOF-MS/MS data. Toxicity analysis showed that most intermediates were more eco-friendly than ATZ. This study developed FeCo 2 O 4 /diatomite with superior catalytic performance, high adaptability, and stability for eliminating refractory organic pollutants.

Fe/Co redox and surficial hydroxyl potentiation in the FeCo2O4 enhanced Co3O4/persulfate process for TC degradation

Tong Zhu,Jinping Jiang,Jisheng Wang,Zhening Zhang,Jiao Zhang,Jing Chang

A magnetic FeCo 2 O 4 /Co 3 O 4 nanocomposite was successfully synthesized by a facile hydrothermal method as an efficient activator for persulfate (PS) activation to degrade tetracycline (TC) in an aqueous solution. TC removal and mineralization efficiencies reached up to 91.63% and 43.57% in 120 min in the FCC-3/PS system, respectively. The mixed-valence of Fe/Co in the nanocomposite catalyst was beneficial for electrons transfer between Co and Fe elements and enhanced the redox circulation of Fe and Co in between divalent and trivalent. Surficial analysis and phosphate adsorption test confirmed the existence of –OH groups on the surfaces of FeCo 2 O 4 /Co 3 O 4 nanocomposite. Fe/Co redox and surficial hydroxyl in the catalyst played significant roles in the TC potentiation degradation, which was contributed by the plenty of adsorbed –OH groups and excellent dispersity of FeCo 2 O 4 in the FeCo 2 O 4 /Co 3 O 4 composite. The sulfate radicals were major species followed by the hydroxyl radicals , and the surficial adsorbed hydroxyl made great contributions to radical generation. The cycling test and intermediate toxicity analysis indicated that the nanocomposite was considered stable and practicable in water treatment . This work demonstrated that the FeCo 2 O 4 /Co 3 O 4 nanocomposite was an effective and environ-friendly catalyst towards PS activation for removing organic pollutants from water.

Hierarchical nitrogen-enriched porous carbon materials derived from Schiff-base networks supported FeCo2O4 nanoparticles for efficient water oxidation

Juntao Liu,Yang Nan,Xiaoxin Chang,Xinzhe Li,Yiyun Fang,Yang Liu,Yu Tang,Xiang Wang,Rong Li,Jiantai Ma

Abundant metal oxides and their composites have attracted great interest in the application of electrochemical energy conversion and storage. In this work, we obtain a hybrid material of FeCo 2 O 4 nanoparticles anchored on hierarchical nitrogen-enriched porous carbon material (denoted as FeCo 2 O 4 @NPC-450 °C) and study its activity for oxygen evolution reaction (OER). NPC-450 °C is prepared by carbonizing a Schiff-base network (SNW) and SNW is melamine-based material own high nitrogen content and rigid molecular backbone. Compared with FeCo 2 O 4 and NPC-450 °C, FeCo 2 O 4 @NPC-450 °C hybrid exhibits remarkable OER performance with a small over potential of mere 330 mv at a current density of 10 mA cm −2 and a small Tafel slope of 50 mV dec −1 . Electrochemical measurements also show that FeCo 2 O 4 @NPC-450 °C present stability for at least 25 h in alkaline solutions. FeCo 2 O 4 @NPC-450 °C shows good performance for OER raises the possibility for cheap and easily prepared catalyst to replace precious metal catalysts .

Hierarchical porous FeCo2O4@Ni as a carbon- and binder-free cathode for lithium−oxygen batteries

Hui Wang,Houzhen Chen,Hongjiao Wang,Lei Wu,Qixing Wu,Zhongkuan Luo,Fang Wang

The electrochemical performance of the lithium−oxygen (Li−O 2 ) batteries largely depends on the material and architecture of the catalytic cathode. In this paper, to avoid the parasitic reactions of carbon and binder with discharge products and reaction intermediates, we proposed an effective design of a free-standing catalytic cathode for Li−O 2 batteries. The FeCo 2 O 4 @Ni electrode consists of FeCo 2 O 4 nanosheets grown directly on nickel (Ni) foam. The resultant hierarchical macroporous/mesoporous structure provides sufficient space for the insoluble discharge product Li 2 O 2 and catalytically active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Consequently, the carbon- and binder-free self-supporting electrode has demonstrated a high discharge capacity with relatively low charge overvoltage and a better cycle performance than the corresponding carbon-based electrodes.

Degradation of methylene blue by a heterogeneous Fenton reaction catalyzed by FeCo2O4-N-C nanocomposites derived by ZIFs

Ting Zhang,Qingqing Ma,Mengqi Zhou,Changyu Li,Jianchao Sun,Weijie Shi,Shiyun Ai

Rationally designing efficient nanomaterials for heterogeneous activation of peroxymonosulfate (PMS) is necessary for environmental remediation. Nitrogen-containing carbon/FeCo 2 O 4 composites (FeCo 2 O 4 -N-C) were prepared by annealing the iron and cobalt in the ZIF-67 (Fe-Co-ZIF) precursor at different reaction temperatures. In the presence of PMS, 400 °C calcined nitrogen-containing carbon/FeCo 2 O 4 composites (FeCo 2 O 4 -N-C-400) was used as catalyst for heterogeneous Fenton degradation of methylene blue (MB) and nearly 100% MB was removed within 10 min without pH adjustment. FeCo 2 O 4 -N-C-400 had excellent catalytic activity profiting from the uniform distribution of bimetals and nitrogen doping, which ensured the exposure of sites with high catalytic activity. Free radical quenching experiments showed that a large number of reactive oxygen species (SO 4 .- and . OH) were the cause of pollutant degradation. At the same time, the possible degradation mechanism of MB in FeCo 2 O 4 -N-C-400/PMS system was proposed. In addition, FeCo 2 O 4 -N-C-400 can still degrade 60% of MB after four cycles, which indicated that the catalyst had long-term catalytic durability and recyclability.

Porous NiCo2O4–FeCo2O4 Nanowire Arrays as Advanced Electrodes for High-Performance Flexible Asymmetric Supercapacitors

Xian Wu,Xiaoya Zhou,Libing Hu,Sheng Zhang,Wangguang Wang,Shaochun Tang

Efficient supercapacitors have attracted wide attention by the exploration of hybrid materials integrating the merits of individual components as promising electrode materials. However, the construction of advanced hybrid structures for highly enhanced electrochemical energy storage is still challenging. Herein, integration of a strong compositional synergy between various bimetallic oxides, MCo2O4 (M = Ni, Fe, and so on), and inducing rich defects for more redox sites are proposed. A novel NiCo2O4–FeCo2O4 hybrid array of nanowires with a large number of nanopores and crystal interfaces is synthesized via hydrothermal reactions and fast calcination. The performance of the NiCo2O4–FeCo2O4/carbon cloth electrode is good and is far beyond that of single-component MCo2O4 electrodes, which exhibits a specific capacity of 490 F/g at 4.0 A/g. The integration of bimetallic redox centers reconstructing the electronic coordination and the nanopores providing highly exposed active surfaces and active sites for highly efficient electrolyte ion diffusion contribute to the enhanced performance. An asymmetric solid-state supercapacitor composed of NiCo2O4–FeCo2O4 and graphene (both using carbon cloth as substrates) as the anode and cathode electrodes, respectively, exhibits a high energy density of 88.9 Wh/cm2 (at a power density of 800 mW/cm2). In particular, the flexible asymmetric device exhibits excellent deformation-tolerant electrochemical stability with nearly overlapping cyclic voltammetry curves at varying bending angles. This work proposes additional methodologies to the fabrication of excellent-performance flexible all-solid-state devices for wearable devices.

Enhanced Ammonia Sensing Performance Based on FeCo2O4/WO3/rGO Ternary Nanocomposites

Haoting Zhang,Yudong Li,Zhenyu Yuan,Yanfeng Lei,Xiaozhi Li,Fanli Meng

Upcycling waste phosphate into CoP/FeCo2O4 heterostructured electrodes: a closed-loop strategy via in-situ phosphorus speciation

Xianyong Hong,Jinghua Li,Yubo Pan,Mingxing Shi,Mingzhu Xia,Fengyun Wang

The redox asymmetry conversion mechanism of adsorbed phosphate during thermal reconstruction remains elusive, limiting the exploitation of spent adsorbents' untapped potential. Here, we report a counterintuitive phenomenon: upon annealing phosphate-saturated CoFe layered double hydroxide (CoFe-LDH) in a reducing atmosphere, the phosphate does not decompose completely but selectively co-generates conductive cobalt phosphide (CoP) and active P O species, forming a self-supported CoP/FeCo 2 O 4 heterostructured electrode. Specifically, the metallic CoP facilitates rapid electron transport, while the P O species synergistically enhance redox kinetics and interfacial compatibility. The pivotal finding is that this in-situ phosphorus speciation challenges the homogeneity assumption inherent to conventional doping paradigms. X-ray photoelectron spectroscopy (P 2p bimodal coexistence) and transmission electron microscopy reveal that the “partial reduction–partial retention” behavior of phosphate arises from synergistic regulation by interlayer confinement effects and metal-phosphate coordination structures within the LDH precursor. Benefiting from this unique configuration, the electrode achieves an exceptional areal capacitance of 3.71 F/cm 2 at 1 mA/cm 2 in 3 M KOH, with 69.74% capacitance retention after 5000 cycles. Density functional theory calculations demonstrate that the built-in electric field at the CoP/FeCo 2 O 4 interface facilitates charge redistribution, reducing the interfacial charge-transfer resistance to 0.48 Ω·cm 2 . This study establishes “phosphorus speciation” as a new principle for concurrently optimizing electronic conductivity and redox activity, offering a paradigm for the function-oriented repurposing of phosphate-laden remediation materials into high-performance energy storage electrodes.

Anchoring FeCo2O4 nanoparticles on reduced graphene oxide: optimizing the loading effect for high-performance lithium-ion battery anodes

Xia Xinzhao,Shen Jiangang,Gong Kunkun,Yang Yubo,Zhang Yuxia,Zong Qianying,Wang Shasha,Tian Zhi,Zhao Taolin

Co 3 O 4 exhibits a high theoretical specific capacity and excellent lithium storage performance, making it a promising lithium-ion battery anode. Nonetheless, its high cost, low intrinsic conductivity, and significant volume change during cycling hinder its widespread application. In this study, Co sites in the spinel Co 3 O 4 was partially substituted with eco-friendly and low-cost Fe to form the bimetallic oxide FeCo 2 O 4 . To enhance conductivity and stabilize the oxide material, reduced graphene oxide (RGO) was incorporated to serve as both a conductive matrix and a mechanical buffer, anchoring the FeCo 2 O 4 nanoparticles to mitigate volume expansion/contraction. The uniform dispersion of FeCo 2 O 4 nanoparticles loaded on the layered RGO architecture was achieved through a facile solvothermal method, effectively mitigating nanoparticle agglomeration and RGO restacking. This approach facilitated the orderly arrangement of FeCo 2 O 4 and enhanced the cycling stability of the electrode. Additionally, the high conductivity of RGO provided efficient pathways for ion and electron transport, further boosting the overall electrochemical performance of FeCo 2 O 4 . At an optimal FeCo 2 O 4 /RGO mass ratio of 10:1, the composite demonstrated an initial specific discharge capacity of 1092.4 mAh g − 1 at 0.5 C, significantly outperforming pure FeCo 2 O 4 (859.2 mAh g − 1 ) under the same conditions. The anchoring effect of RGO substantially enhanced the electrochemical performance of FeCo 2 O 4 . This work underscores the efficacy of synergistic composite design and provides a practical approach for developing advanced bimetallic oxide anodes for high-energy-density lithium-ion batteries.

The Built-in Electric Field Regulates the d-band Center of the FeCo2O4/ZnCdS Heterojunction to Enhance Photocatalytic Hydrogen Evolution

Shuai Wang,Yihu Ke,Fei Jin,Youji Li,Zhiliang Jin

Noble metal nanoparticle co-catalysts offer high photocatalytic activity but are costly and scarce, driving the search for efficient, economical alternatives. We constructed a FeCo 2 O 4 /ZnCdS composite catalyst using electrostatic self-assembly. Optimizing the FeCo 2 O 4 loading to 10 wt% achieved a remarkable hydrogen production rate of 9080 μmol g −1 h −1 −3.49 times higher than pristine ZnCdS and exceeding precious metal co-catalysts like Au. Kelvin probe force microscopy, X-ray photoelectron spectroscopy, and density functional theory (DFT) calculations reveal an S-scheme heterojunction forms between FeCo 2 O 4 and ZnCdS. The resulting internal electric field efficiently drives directional charge migration and significantly suppresses electron-hole recombination. DFT further shows the interface electric field shifts the d-band center, optimizing reactant molecule adsorption. This avoids catalyst deactivation from strong adsorption while overcoming the energy barrier from weak adsorption, creating an ideal moderate-strength activated state. This work deepens understanding of S-scheme mechanisms and provides a new strategy for economical photocatalytic hydrogen production. Graphical The built-in electric field in FeCo 2 O 4 /ZnCdS heterojunctions regulates the d-band center to optimize hydrogen adsorption energy. An S-scheme charge transfer mechanism achieves a photocatalytic hydrogen evolution rate of 9080 μmol g − 1 h − 1 , surpassing noble-metal cocatalysts. Density functional theory and Kelvin probe force microscope studies confirm that interfacial electric field engineering enhances carrier separation and reaction kinetics, providing an efficient noble-metal-free strategy.

Self-supported spinel FeCo2O4 nanowire array: an efficient non-noble-metal catalyst for the hydrolysis of NaBH4 toward on-demand hydrogen generation

Shuai Hao,Libin Yang,Liang Cui,Wenbo Lu,Yingchun Yang,Xuping Sun,Abdullah M Asiri

NaBH4 has been considered as one of the most advantageous candidates for chemical hydrogen storage, but it is still a huge challenge to design efficient non-noble-metal catalysts for on-demand hydrogen generation from NaBH4 hydrolysis. In this paper, we demonstrate for the first time that a spinel FeCo2O4 nanowire array supported on carbon cloth (FeCo2O4 NA/CC) behaves as an efficient earth-abundant catalyst toward NaBH4 hydrolysis in alkaline solutions with an activation energy of 44.98 kJ mol−1. Such FeCo2O4 NA/CC offers a hydrogen generation rate of 2551 ml min−1 g−1 under ambient conditions, with good stability and reusability. Its use as an ON/OFF switch for on-demand hydrogen generation is also demonstrated successfully.

A triple-layered PPy@NiCo LDH/FeCo2O4 hybrid crystalline structure with high electron conductivity and abundant interfaces for supercapacitors and oxygen evolution

Jing He,Zhufeng Hu,Kuan Deng,Renjun Zhao,Xingbin Lv,Wen Tian,Yu Xin Zhang,Junyi Ji

A rational structural design of electrodes with high electron conductivity, sufficient material interfaces/defects and a regulated charge transfer pathway can be applied in broad practical electrochemical application fields. A triple-layered PPy@NiCo LDH/FeCo2O4 hybrid with a tri-metal hybrid nanowire and conductive PPy coating layer is fabricated via a one-step hydrothermal reaction and in situ polymerization. NiCo LDH/FeCo2O4 nanowire arrays with a layered crystalline structure are synthesized via an in situ dissolution-growth method, where the partially etched nickel foam substrate subsequently acts as the Ni source. The NiCo LDH/FeCo2O4 nanowire arrays together with the ultrathin PPy coating layer can form bi-continuous conductive networks, numerous crystalline edges and structural interfaces to increase the electron transfer rate and the active/adsorption sites, which can further promote the energy storage and electrocatalytic activity. The bi-functional PPy@NiFeCo/NF-4 electrode exhibits a high areal capacitance (9.24 F cm−2 at 5 mA cm−2) and excellent rate capability (90.5% retention from 5 to 30 mA cm−2) as a supercapacitor and achieves a small overpotential (244 mV at 50 mA cm−2) and Tafel slope (64.39 mV dec−1) as an electrocatalytic OER electrode.