查找使用阿拉丁产品的科研文献

Cobalt Phosphide-Doped Porous Carbon Derived from Co-MOF/zinc Phosphate as a Bifunctional Electrocatalyst for Hydrogen, Oxygen Evolution Reactions

Xiao Lili,Yong Zishuang,Jiang Jin,Chen Miao,Cai Yutong,Zhou Zhiqiang

Widespread adoption of electrolytic water splitting for hydrogen production is limited by the high overpotential and slow kinetics of the oxygen evolution reaction. This work presents a bifunctional electrocatalyst of cobalt phosphide-doped porous carbon electrocatalyst (CoP/Co 2 P/C). The catalyst was synthesized via direct pyrolysis of a composite precursor (denoted as Co/Zn-PO@Co-MOF), which consisted of spherical cobalt/zinc phosphate (Co/Zn-PO) coated with Co-based metal-organic framework. The spherical Co/Zn-PO served as a novel and safer phosphorus source, eliminating the need for conventional NaH 2 PO 2 carbonization which releases toxic gases. Although minimally incorporated into the composite precursor, Ni 2+ played two key roles: it primarily functioned to assist the coordination of Co 2+ with 2-methylimidazole on the surface of Co/Zn-PO, and additionally modulated the resulting CoP/Co 2 P ratio. Moreover, the carbonization temperature was a critical variable in converting Co/Zn-PO@Co-MOF into CoP/Co 2 P and affected the final ratio between them. Based on the interfacial synergistic effect between CoP and Co 2 P, along with three catalytic active sites of Co, P and Pyridinic N, the optimized CoP/Co 2 P/C achieved a current density of 10 mA cm − 2 at low overpotentials (η 10 ) of 204 mV for HER and 339 mV for OER. The performance of CoP/Co 2 P/C remains comparable to that of most recently reported cobalt phosphide-based catalysts. Graphical The alternative text for this image may have been generated using AI.

Construction of closed bipolar electrochemiluminescence sensor based on Co-MOF-derived Au/CoO-modified carbon cloth for uric acid detection

Dong Huahua,Qv Kaige,Zhu Qunyan,Li Jinshuo,Liu Chang,Zhang Lin,Yang Wensheng

A closed bipolar electrode-based electrochemiluminescence (cBPE-ECL) sensor was developed for wireless uric acid (UA) detection. In the cBPE-ECL sensor design, a cobalt-based metal–organic framework (Co-MOF)-derived Au/CoO-modified carbon cloth (Au/CoO-C/CC) electrode served as a polarized anode for UA oxidation, where the generated faradaic current triggered the cathodic ECL of [Ru(bpy) 3 ] 2+ -[S 2 O 8 ] 2− at the polarized cathode electrode, enabling both quantitative and visual UA detection. The polarized anode was fabricated by incorporating Au nanoparticles into a Co-MOF structure on carbon cloth (CC), yielding an open architecture with enhanced charge transfer capabilities that significantly improved electrocatalytic activity toward UA. The as-prepared cBPE-ECL sensor exhibited excellent analytical performance, featuring a wide linear range (10–1000 µM), low detection limit (6 µM), high stability, good reproducibility, and strong anti-interference capabilities. The practical utility of this cBPE-ECL sensing platform was validated through successful UA detection in fetal bovine serum and artificial serum samples, achieving recoveries between 96.4 and 103.4%, demonstrating its potential for UA detection in clinical and biomedical applications. Graphical abstract

Lattice oxygen-mediated Co–O–Fe formation in Co-MOF via Fe doping and ligand design for efficient oxygen evolution

Tao Zhao,Dazhong Zhong,Qiang Fang,Xin Zhao,Runxin Du,Genyan Hao,Guang Liu,Jinping Li,Qiang Zhao

The rational design of metal-organic frameworks (MOFs) provides potential opportunities for improving energy conversion efficiency. However, developing efficient MOF-based electrocatalysts remains highly challenging. Herein, a strategy involving strain engineering is developed to promote the electrocatalytic performance of MOFs by optimizing electronic configuration and improving the active site. As expected, the optimized CoFe–BDC NO 2 exhibits a low overpotential of 292 mV at 10 mA cm –2 and a small Tafel slope of 31.6 mV dec –1 as oxygen evolution reaction (OER) electrocatalyst. Notably, when CoFe–BDC NO 2 is prepared on Nickel foam (NF), the overpotential is only 345 mV at 1 A cm –2 , which ensures efficient water oxidation properties. Integrating CoFe–BDC NO 2 /NF anode in membrane electrode assembly (MEA) for overall water splitting and CO 2 reduction reaction (CO 2 RR) tests, the results show that the cell voltages of CoFe–BDC NO 2 /NF are 3.14 and 3.09 V at 300 mA cm –2 (25 °C), respectively, indicating that MOFs have various practical application prospects. The research of the structure-performance relationship reveals the lattice oxygen oxidation mechanism (LOM) where the Co-O-Fe bond is formed during the OER process by changing the electronic environment and coordination structure of CoFe–BDC NO 2 , and with high valence Co as active center, which provides a deep understanding of the structure design of MOFs and their structural transformation during OER.

A renewable screen-printed electrode based on magnetic NiCo@N-doped carbon nanotubes derived from Co-MOF for ractopamine detection

Zheng Mingyu,Qian Xinmei,Li Chunxiang,Wang Jinglun,Huang Haowen,Deng Keqin

A renewable electrochemical screen-printed electrode (SPE) is proposed based on magnetic bamboo-like nitrogen-carbon (N–C) nanotubes loaded with nickel–cobalt alloy (NiCo) nanoparticles (NiCo@N-CNTs) for the determination of ractopamine (RAC). During the preparation of NiCo@N-CNTs, Co-MOF-67 (ZIF-67) was firstly synthesized, and then blended with dicyandiamide and nickel acetate, followed by a one-step pyrolysis procedure to prepare NiCo@N-doped carbon nanotubes. The surface morphology, structure, and chemical composition of NiCo@N-CNTs were characterized by SEM, TEM, XRD, XPS, and EDS. The electrocatalytic and electrochemical behavior of NiCo@N-CNTs were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results demonstrated that NiCo@N-CNTs possessed remarkable conductivity and electrocatalysis to the oxidation of ractopamine (RAC). By using screen-printed electrode (SPE), NiCo@N-CNTs, and a designed base support, a magnetic RAC sensor (NiCo@N-CNTs/SPE) was successfully constructed. It presented a detection linear range of 0.05–80 μM with a detection limit of 12 nM (S/N = 3). It also exhibited good sensitivity, reproducibility, and practicability in spiked real pork samples. Since the adhesion of NiCo/N-CNTs on SPE was controlled by magnet, the NiCo@N-CNTs was easily detached from the SPE surface by magnetism and thus displayed excellent renewability. This work broadened insights into portable devices for on-site and real-time analysis. Graphical Abstract

Petal-like hierarchical Co3O4/N-doped porous carbon derived from Co-MOF for enhanced peroxymonosulfate activation to remove tetracycline hydrochloride

Qingqing Li,Zhujuan Ren,Yutong Liu,Chibin Zhang,Jiadi Liu,Rong Zhou,Yuanqing Bu,Feifei Mao,Hua Wu

Developing hierarchical and efficient catalysts with multiple active sites to activate peroxymonosulfate (PMS) for the degradation of persistent organic contaminants is crucial, whereas it's still a challenge. Herein, a novel petal-like N -doped porous carbon embedded with ultrafine cobalt oxide nanoparticles (NPs) (named as Co 3 O 4 /NC) was unprecedentedly fabricated via the pyrolysis of N -enriched Co-MOF (named as Co-TA), where the unique hierarchical structure, rich active sites and large specific area were contributed to improve the excellent catalytic activity toward tetracycline hydrochloride (TCH). As expected, the removal efficiency of TCH in Co 3 O 4 /NC/peroxymonosulfate system was 96.4 % within 30 min, extraordinary superior to direct air-calcining nano-Co 3 O 4 , commercial Co 3 O 4 and Co-TA, in which the kinetic constant was 10.4 times higher than pure Co-TA. Besides, above 97 % removal efficiency of TCH was maintained over a wide pH range of 5–9, and 71 % of total organic carbon (TOC) could be eliminated. The TCH degradation was mainly characterized by the coexistence of multiple active substances using EPR analysis, where SO 4 · − and 1 O 2 were the dominant contributors. The degradation pathways of TCH were also clarified based on theoretical calculation and HPLC-TOF-MS 2 data. This work can extend the application of metal–organic frameworks (MOFs)-derived nanocatalysts in the environment field, and may offer a promising metal oxide heterogeneous catalyst for the rapid elimination of persistent organic pollutants by sulfate radical-based advanced oxidation processes (SR-AOPs).

Enhanced composite Co-MOF-derived sodium carboxymethyl cellulose visual films for real-time and in situ monitoring fresh-cut apple freshness

Zhepeng Zhang,Yang Zhang,Chen Wang,Xianjin Liu,Hesham R. El-Seedi,Paula L. Gómez,Stella M. Alzamora,Xiaobo Zou,Zhiming Guo

Natural biopolymers have extensively applications in intelligent food packaging due to their renewable nature, easy availability, environmental-friendly, low-cost and excellent processibility. Recently, the integration or embedding of nanocomposites on polymer substrates to improve the multi-faceted performance of packaging materials has attracted widespread attention. Herein, the irregular spherical Co-based metal-organic framework (Co-MOF) loaded with phenol red (PR) and bromothymol blue (BTB) were fabricated, resulting in absorbed nanocomposites Co-MOF/PR and Co-MOF/BTB. Afterward, the nanocomposites were integrated into a sodium carboxymethyl cellulose (CMC-Na) substrate to prepare a CO 2 -responsive packaging material (CMC-Na/PR/Co-MOF and CMC-Na/BTB/Co-MOF) for real-time and in-situ monitoring apple freshness. The synthesis of Co-MOF and the hydrogen-bonding interactions between MOF and pigments adsorption were confirmed. The advantages exhibited by the film with adding Co-MOF, including excellent hydrophobicity and water resistance, improved time-temperature stability and mechanical properties, were explored. Notably, the Co-MOF-based composite film exhibited enhanced UV–visible barrier, anti-migration performance of pigment, and thermal stability. Finally, a significant linear response (R 2  = 0.9923 and 0.9781) between the total color difference values (ΔE) of Co-MOF-based film and hardness and total soluble solids (TSS) of fresh-cut Fuji apples at 4 °C was demonstrated, respectively. These findings indicate the significant potential of CMC-Na-based composite film containing multifunctional MOF nano-filler as a visual monitoring system, which will pave the way for fresh-cut fruit intelligent packaging.

Electron redistribution via two-dimensional van der Waals heterojunctions boosts trifunctional electrocatalysis in sandwich-like structured Co-MOF/TiN/NC composite

Mengyao Zhao,Can Sun,Xiang Li,Ya Zhao,Guosheng Shao,Peng Zhang,Yige Zhao

Two-dimensional van der Waals heterojunctions (2D vdWHs) have received significant attention owing to their extraordinary properties such as the reduced energy barriers and efficient charge transfer. However, there is limited research about the construction of 2D vdWHs in electrocatalysts for improving multifunctional performance. Herein, we report a sandwich-like structured Co-MOF/TiN/NC-240 electrocatalyst with 2D vdWHs by one-step high-temperature solid-state and room-temperature ultrasonication methods, with 2D Co-MOF nanosheets uniformly assembled on the TiN/NC substrate. Ultraviolet Photoelectron Spectroscopy (UPS) reveal that the work function difference between Co-MOF and TiN/NC drives electron transfer from TiN/NC to Co-MOF, thereby modulating the metal oxidation state. The Co-MOF/TiN/NC-240 electrocatalyst exhibits boosted trifunctional electrocatalytic performances for ORR, OER, and HER , which can be attributed to the successful construction of 2D vdWHs, inducing effective electron redistribution via the heterogeneous interface and increasing the number of active sites. Moreover, the zinc-air battery (ZAB) and water-splitting device based on Co-MOF/TiN/NC-240 exhibit enhanced discharge capacity and superior efficiency, respectively. This study not only provides an effective design strategy to develop trifunctional electrocatalysts by constructing 2D vdWHs but also offers valuable insights into the enhanced electrocatalytic performance in the sustainable energy field.

Calcination/phosphorization of dual Ni/Co-MOF into NiCoP/C nanohybrid with enhanced electrochemical property for high energy density asymmetric supercapacitor

Qingfeng Zhou,Yun Gong,Keyu Tao

Binary metal compounds have higher conductivity and richer redox reactions due to the co-existence and synergism of different transition metals. Besides, carbon in composite materials has the advantage of enhancing electronic conductivity to promote fast electron transmission. Herein, a series of Ni m P n /C, Ni 2 P/C, Co 2 P/C and Ni x Co 2-x P/C nanohybrids with different Ni/Co molar ratios were synthesized by in-situ calcination/phosphorization of MOF precursors. These nanohybrid materials were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive spectrometer and electrochemical tests. The NiCoP/C material possesses a granular structure with NiCoP nanoparticles anchored in a large number of carbon. Taking advantage of the bimetallic synergism and carbon anchoring effect, the as-prepared NiCoP/C sample delivers the most prominent specific capacities of 775.7C g −1 at 1 A g −1 , and 582.4C g −1 at 20 A g −1 (20-fold) with a superior rate capability of 75.1% retention, much superior to those of the corresponding Ni m P n /C, Ni 2 P/C, Co 2 P/C, other Ni x Co 2-x P/C samples and various reported metal phosphide nanostructures/nanocomposites. Furthermore, the constructed NiCoP/C//activated carbon asymmetric supercapacitor can exhibit a high energy density of 47.6 Wh kg −1  at a power density of 798.9 W kg −1 , which was superior to those previously reported of Ni/Co phosphide nanomaterials.

Green and efficient synthesis of Co-MOF-based/g-C3N4 composite catalysts to activate peroxymonosulfate for degradation of the antidepressant venlafaxine

Jun Luo,Yuxuan Dai,Xiaoming Xu,Yazi Liu,Shaogui Yang,Huan He,Cheng Sun,Qiming Xian

Based on single metal–organic framework (MOF) composite catalyst ZIF-67/ g -C 3 N 4 (ZG), the composite catalysts ZIF-67/MOF-74(Ni)/ g -C 3 N 4 (ZNG) and ZIF-67/MIL-100(Fe)/ g -C 3 N 4 (ZMG) with double MOFs were synthesized, used to effectively activate peroxymonosulfate (PMS) for degrade venlafaxine (VEN). Various characterization methods (XRD, FT-IR, Raman, SEM , EDS, TEM and TG) showed that ZIF-67 and g -C 3 N 4 ; ZIF-67, MOF-74(Ni) and g -C 3 N 4 ; as well as ZIF-67, MIL-100(Fe) and g -C 3 N 4 successfully formed heterostructures . The series of catalytic degradation results showed that within 120 min, the degradation rate of VEN by ZMG achieved 100% and the mineralization rate reached 51.32%. The removal rate of VEN by ZNG was 91.38%, while that by ZG was only 27.75%. Free radical quenching tests and EPR further confirmed the production of OH and SO 4 − , which could be conducive to the degradation of VEN. The mechanism analysis of PMS activation confirmed that the interaction of Fe 2+ / Co 3+ was stronger than that of Ni 2+ / Co 3+ , and it was an important driving force to significantly enhance the synergistic effect. Finally, Gauss theory calculation and HPLC-MS/MS were used to analyze the intermediate products of VEN. It was verified that the main chemical reactions in the degradation process of VEN were hydroxylation , dehydration, demethylation and tertiary amine substitution.

Carbon Cloth Loaded NiCo2O4 Nano-Arrays to Construct Co-MOF@GO Nanocubes: A High-Performance Electrochemical Sensor for Non-Enzymatic Glucose

Bairui Tao,Jiao Li,Fengjuan Miao,Yu Zang

Fabrication of well-aligned Co-MOF arrays through a controlled and moderate process for the development of a flexible tetrabromobisphenol A sensor

Shiyuan Wang,Yao Chen,Mei Long,Wanyu Li,Yiran Huang,Shiyi Lai,Guiping Yang,Yang Song,Jinfa Chen,Guangxia Yu

Tetrabromobisphenol A (TBBPA) has attracted a great deal of attention due to its side effects and potential bioaccumulation properties. It is of great importance to construct and develop novel electrochemical sensors for the sensitive and selective detection of TBBPA. In the present study, cobalt (Co) based metal–organic frameworks (MOFs) were synthesized on carbon cloth (CC) by using cobalt nitrate hexahydrate and 2-methylimidazole. The morphological characterization was carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The results showed that Co-MOFs/CC have a leaf-like structure and abundant surface functional groups. The electrochemical properties of the sensor were investigated by differential pulse voltammetry (DPV). The effects of different ratios of metal ions to organic ligands, reaction temperature, time, concentration, pH value of the electrolyte, and incubation time on the oxidation peak current of TBBPA were studied. Under the optimal conditions, the linear range of the designed sensor was 0.1 μM–100 μM, and the limit of detection was 40 nM. The proposed sensor is simple, of low cost and efficient, which can greatly facilitate the detection tasks of environmental monitoring workers.

Preparation of a cobalt metal-organic framework (Co-MOF) and its application as a polypropylene flame retardant by compounding with melamine polyphosphate

Ya Xu,Ru Zhou,Gang Ma,Lisha Deng,Huimin Liu,Yanming Ding,Juncheng Jiang

A cobalt metal-organic framework (Co-MOF) was successfully prepared, and its combination with melamine polyphosphate (MPP) was studied to enhance the fire retardant properties of polypropylene (PP) composites. The morphology, composition, and structure of PP/MPP/Co-MOF composites were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The maximum limiting oxygen index of the PP/MPP/Co-MOF composite was 26.8%, which is 49% higher than that of pure PP and its combustion grade reached the V-0 level. When 2 wt% Co-MOF was added, the carbon residue of the composite reached 19.6 wt%, peak heat release rate was significantly reduced, smoke emission was suppressed, fire growth index was significantly reduced, and the fire risk of the composite was effectively reduced. Analysis of the carbon residue showed that aggregated carbon spheres were present on the carbon residue surface of the composite material supplemented with Co-MOF. The generation of carbon spheres effectively prevented the heat exchange and release of combustible gas during the combustion of the composite material, significantly improving the flame retardancy and stability of the material. As a new material, MOF has great innovation and necessity in researching polymer flame retardant. Moreover, the latest composite materials synthesized in this paper contribute to environmental safety to a great extent.