SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Guanhan Chen,Hongjie Wang,Wenyi Dong,Wenhui Ding,Feifei Wang,Zilong Zhao,Yuxiong Huang
Cobalt oxide (Co 3 O 4 ) activated peroxymonosulfate (PMS) system was extensively studied due to its excellent catalytic performance. However, the relatively high cobalt (Co 2+ ) leaching (up to 2 mg/L) would pose high ecotoxicological risks. Herein, we identified the existence of Co(OH) 2 on the surface of Co 3 O 4 were the major source of Co 2+ leaching in the Co 3 O 4 activated PMS system. Furthermore, the Co 2+ leaching was effectively suppressed by converting Co(OH) 2 to Co 3 O 4 via pyrolysis treatment. In addition, reduced graphene oxide (rGO) was engaged to enhance the degradation performance of antibiotics in the Co 3 O 4 activated PMS system. The oxygen functionalities of rGO would catalyze PMS to generate sulfate radicals (SO 4 − ) and trigger the non-radical pathway of singlet oxygen ( 1 O 2 ). We have achieved outstanding catalytic performance for carbamazepine (CAZ) degradation with low Co 2+ leaching, as CAZ (5 mg/L) could be completely degraded in 30 min. Combining experimental investigation and theoretical calculation, we also revealed the degradation pathways and mechanisms that CAZ would be oxidized and detoxified by 1 O 2 and SO 4 − . We have provided a simple approach to inhibit the Co 2+ leaching and enhance the catalytic performance of Co 3 O 4 activated PMS system for the effective control of antibiotics.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2021
·Vol. 152
·期 6
·1719-1728
·
IF 3.186
Feng Yi,Jiang Xiaoli,Tang Lin,Lin Dunmin,Huo Yu,Xie Fengyu,Zheng Qiaoji
Abstract Exploiting highly active and robust non-noble-metal electrocatalysts for oxygen evolution reaction (OER) occupies an important position in alleviating energy crisis and maintaining social sustainability. Herein, we have grown Co(OH) 2 nanoarrays in situ on Mn-doped NiFe LDH nanosheets to construct Mn-doped NiFe LDH@Co(OH) 2 /NF (MNF@Co(OH) 2 /NF) with core–shell structure. Due to the optimized electronic structure by manganese ion doping and the high density exposure of active sites induced by cobalt hydroxide coating, the MNF@Co(OH) 2 /NF exhibits excellent OER performances, which possesses ultralow overpotentials of 193 and 244 mV at the current densities of 10 and 100 mA cm −2 separately, and possesses a small Tafel slope of 48.4 mV dec −1 . This work offers a new perspective for the rational construction of efficient OER electrocatalysts with multi-dimensional nanostructures to improve the catalytic activity. Graphic Abstract
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 24
·16263-16275
·
IF 2.993
Li Jiali,Kong Xianggui,Jiang Meihong,Lei Xiaodong
Up to now, although tremendous effort has been made in exploring Pd-based catalysts for the Suzuki–Miyaura coupling reactions, there is still much room to enhance its catalytic performance by synthesis catalyst with define-designed and tailored structure. Herein, a new kind of Pd-based structured catalyst with hierarchical hollow structure (Pd/Co(OH) 2 /Cu(OH) 2 /copper foam) has been successfully synthesized by three facile steps. As framework, the hierarchical hollow nanoarray structure of Co(OH) 2 /Cu(OH) 2 /copper foam is fabricated by immersion and electrolytic deposition methods. Uniformly dispersed Pd nanoparticles with a narrow size distribution (1.5 ± 0.2 nm) are anchored on the surface of the hierarchical nanotube array through an in situ spontaneous redox reaction between Co(OH) 2 and PdCl 4 2− without any surfactant at room temperature. Compared with other synthesis approaches, it just takes less than 1 h for the whole fabrication process in our strategy, exhibiting very high efficiency. In order to evaluate the catalytic performance of the as-prepared structured catalyst, 16 kinds of reagents were chosen as substrates for Suzuki–Miyaura coupling reaction, exhibiting excellent activity and reusability under mild conditions. We hope this simple and efficient method will open a new strategy to design and prepare structured catalysts.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 5
·期 6
·2629-2639
·
IF 8.262
Xin Tong,Dajun Wu,Chi Zhang,Kenan Lian,Dayuan Xiong,Shaohui Xu,Yiping Zhu,Ruijuan Qi,Rong Huang,Lianwei Wang,Paul K. Chu
Conducting the hydrogen evolution reaction (HER) in an alkaline environment using a non-precious transition metal catalyst with high efficiency is challenging. Here, we report excellent HER activity achieved using three-dimensional (3D) tetsubo-like Co(OH)2 nanorods on a macroporous electrically conductive network (MECN) synthesized by a hydrothermal method. This unique framework comprises three levels of porous structures, including a bottom-ordered MECN substrate, an intermediate layer of vertically porous Co(OH)2 nanowires with a mean diameter of 100 nm and length of about 2 μm, and outmost Co(OH)2 nanosheets (≈20 nm). The 3D array structure with a large aspect ratio provides a large specific surface area and exposes more active sites to catalyze electrochemical reactions at the electrode–electrolyte interface. Compared with Co(OH)2 nanosheets on an MECN and foamy Co(OH)2 on an MECN structure, the synthesized architecture has excellent HER catalytic reactivity, including a low potential of −69.2 mV vs. RHE, a cathodic current density of 10 mA cm−2, a small Tafel slope of 61.9 mV dec−1, a high current density, and robust catalytic stability in 1 M KOH, and is promising in HER applications.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Fei Duan,Yunqin Hu,Junfeng Lin,Mingyue Li,Hao Wu,Zhiqing Cui,Caihong Fang
To develop non-noble electrocatalysts with high activity and stability for oxygen evolution reaction (OER)/urea oxidation reaction (UOR) is crucial to boost the efficiency of overall water/urea splitting reaction (OWS/OUS) for H 2 production. Herein, we synthesized novel CeO 2 /Co(OH) 2 /FeS nanosheet arrays on nickel foam (CeO 2 /Co(OH) 2 /FeS@NF) through a simple two-step hydrothermal and following solvothermal routine. In this special structure, the ultra-thin 2D nanosheet morphology can adequately offer large contact area and thus abundant of active sites, facilitating significantly the mass transfer. Furthermore, the incorporation of FeS into CeO 2 /Co(OH) 2 will not only modify the electron structure but also provide a number of phase interfaces, which can improve the inherent electron conductivity and promote the electron transport. More importantly, the rich oxygen vacancies (O v ) sites can vary the coordination of metal centers, modulating both the charge distribution and M−O bonding strength. As results, the CeO 2 /Co(OH) 2 /FeS@NF shows superior low overpotentials of 178 mV/1.30 V at 10 mA cm −2 to OER/UOR. The activity keeps its low value of 232 mV/1.375 V even when the current density was increased to as high as 300 mA cm −2 . More importantly, the electrode of CeO 2 /Co(OH) 2 /FeS@NF//CeO 2 /Co(OH) 2 /FeS@NF just requires a low cell voltage of 1.41 V to realize OUS at a current density of 10 mA cm −2 . Specifically, we also realized solar-driven H 2 production. Plenty of H 2 bubbles were continuously generated with a high speed of 600 L h −1 m −2 on the working electrode surface once the solar panel was placed under the natural sunlight.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Chaojie Lyu,Jiarun Cheng,Kaili Wu,Jiwen Wu,Ju Hao,Yuanyuan Chen,Huichao Wang,Yunguo Yang,Ning Wang,Woon-Ming Lau,Jinlong Zheng
Transition metal-based electrocatalysts are the promising candidates to substitute noble metal-based catalysts for water electrolysis, owing to its abundant earth reserves and inexpensive fabrication costs. Interface engineering and cation doping engineering are verified as the effective methods to improve the sluggish electrocatalytic performance of transition metal-based electrocatalysts. Here, we synthesized a self-supported heterostructure of Ce doped Co(OH) 2 nanosheets/CoP nanowires on the support of nickel foam (Ce-Co(OH) 2 /CoP/NF) by simple hydrothermal method , low-temperature phosphorization method. The Ce atom doping can lead to lattice distortion and abundant superficial defects on crystal surface, which will generate more active sites and faster charges transformation. The heterointerface between Ce-Co(OH) 2 and CoP also can lead to electronic structure modulation at interface domain, which not can induce much fresh active sites in this area, but can optimize the active sites to the optimal state for superior catalytic activity. Benefitting from these, it only needs the overpotentials of 253 and 56 mV to realize 10 mA/cm 2 for OER and HER under 1 M KOH solution, which is much enhance than single-phased samples. As the bifunctional electrocatalyst for two-electrode system, it merely requires 1.53 V to attain 10 mA/cm 2 in 1 M KOH, and it also exhibits outstanding overall water splitting performance in alkaline natural electrolyte, along with excellent catalytic long-time durability. In addition, the Ce-Co(OH) 2 /CoP/NF-based electrolyzer also could achieve energy-saving hydrogen production, and simultaneously oxidative degradation of organic materials or biomass upgrading at anode under lower voltages. This work paves a novel idea to fabricate high-efficient bifunctional electrocatalysts for energy-saving H 2 production.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Le Gao,Yawen Li,Guifang Li,Jiaqi Huo,Lishan Jia
Interface engineering as an effective material modification method can regulate local corresponding interfacial geometry and electronic structures, thus enabling a higher intrinsic activity for the oxygen evolution reaction (OER). Herein, we carefully designed p-p heterojunction precursor Co4-MOF@La(HCO 2 ) 3 with internal electric field through electrostatic adherence, which then in-situ transformed into p-p type heterojunction electrocatalyst (Co(OH) 2 )4@La(OH) 3 under KOH activation strategy. The one-step in-situ conversion of (Co(OH) 2 )4@La(OH) 3 generated the interface with significant difference in metal atomic radius and exhibits fascinating nanostructures, which enhances the specific surface area and increases the number of active sites compared with the parent material. Impressively, the obtained material (Co(OH) 2 )4@La(OH) 3 demonstrates satisfying electrocatalytic activity in OER with a low overpotential of only 233 mV to reach a current density of 20 mA cm −2 , and excellent stability for 50 h at 10 mA cm −2 in alkaline medium. In-situ Raman technique indicates that multivalent Co centers are the true active sites during the OER process. Based on density functional theory (DFT) calculation results, La atoms possess empty d orbitals, which are beneficial to facilitate charge transfer from Co to La at the heterojunction interface. Meanwhile, the introduction of La atoms changes the coordinated environment around the adjacent atoms at the interface, which induces the upshift of the d-band center for Co atoms and increases the binding strength of the adsorbed oxygen intermediate.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Xi Tao,Poyueh Pan,Taobo Huang,Long Chen,Haodong Ji,Juanjuan Qi,Fengbin Sun,Wen Liu
Sulfachloropyridazine (SCP) was commonly used as a broad-spectrum sulfonamide antibiotic and hard to be removed through traditional sewage treatment process. In this study, we developed a simple and controllable strategy to realize in-situ construction of Co(OH) 2 nanoparticles decorated urchin-like WO 3 (Co(OH) 2 /WO 3 ), which could efficiently remove SCP through peroxymonosulfate (PMS) activation. Some tiny nanoparticles of Co(OH) 2 decorated on the spines/nanorods or surfaces of urchin-like WO 3 by transmission electron microscopy (TEM) analysis. The obtained 10 wt% Co(OH) 2 /WO 3 realized completely removal of SCP (degradation efficiency 100%) with a high reaction rate constant ( k 1 ) of 0.88 min −1 within 3 min at optimal pH 7. That was because the urchin-like WO 3 with numerous adsorption functional groups on its surface ( e.g. , W = O and –OH bonds) could adsorb the Co 2+ easily to form CoOH + , which was perceived the rate-limiting step for PMS activation and generating radicals. Radical quenching experiments indicated that SO 4 •− played a more significant role than HO • radicals. Density functional theory (DFT) calculation revealed that the atoms of SCP with high Fukui index ( f − ) were active sites, which preferred to be attacked by the electrophilic SO 4 •− and HO • radicals. The toxicity of the intermediates by SCP degradation was evaluated by quantitative structure–activity relationship (QSAR) prediction through Toxicity Estimation Software Tool (T.E.S.T.). The possible degradation pathway and catalytic mechanism for SCP removal were proposed. Considering the good catalytic properties of Co(OH) 2 /WO 3 -PMS, the material will show great application potential in the removal of emerging contaminants in water.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2024
·Vol. 16
·期 16
·8162-8176
·
IF 5.8
Xinmeng Zhang,Mingyue Bai,Lei Ge,Yuanyuan Yao
The slow redox rate of hydrogen peroxide (H2O2) in neutral environments makes the H2O2 sensor inadequate for the detection of low levels of signalling molecules. The aim of this study is to fabricate a flexible sensing electrode by hydrothermally loading micro-nanometer Ni and Co(OH)2 on carbon cloth (CC) and electrochemically depositing poly(3,4-ethylenedioxythiophene) (PEDOT) on the surface of the electrode. The sensor presented high sensitivity (10.43 mA mM−1 cm−2), a wide detection range (0.033–120.848 mM), a low detection limit (0.92 nM), high stability, and excellent anti-interference performance in neutral solutions. Ni–Co(OH)2 provides abundant active sites while CC solves their agglomeration phenomenon and conductivity. The PEDOT film offers heightened conductivity, hydrophilicity, interfacial stability, and an electrochemically active surface area (ECSA). The side area of the chrysanthemum petal like PEDOT is 39 ± 7 times the bottom area, and PEDOT increases the ECSA of the composite to six times that of CC. Electrochemical precise control of PEDOT morphology to improve sensor performance provides a new strategy for the application of PEDOT in sensors.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Yang Liu,Hailong Feng,Weiyi Li,Xueping Wang,Guoxiang Huang,Longxia Wang,Xingqiu Li,Yuxing Xie,Chenglu Liang
Catalysts in-situ reconstructed from transition metal sulfides for oxygen evolution reaction (OER) have been regarded as potential alternatives for the noble metal catalysts . Intriguingly, it was found that the self-optimized SO 4 2− @Cu doped Co(OH) 2 catalyst was reconstructed from bimetallic sulfide of CuCo 2 S 4 . During the OER process, the copper was partially leached and meantime doped into the in-situ generated Co(OH) 2 with SO 4 2− adsorption, while only oxides were discovered in counterparts of mono-metal sulfides. As a result, the SO 4 2− @Cu doped Co(OH) 2 catalyst exhibited superior OER performances, with low overpotentials of 211/272 mV to achieve the current densities of 10/100 mA cm −2 , exceeding the counterparts reconstructed from mono-metal sulfides. Experimental and theoretical results suggested that the in situ generated Cu doped Co(OH) 2 possessed thin and loosely layered structure with expanded lattice spacing (lattice spacing expanded from 0.28 nm to 0.46 nm) due to the SO 4 2− adsorption, making the intermediates more accessible to the active centers. In addition, the catalyst surface changed from hydrophobicity to super hydrophilicity , which greatly accelerated the mass transfer. This work indicated that the in-situ reconstruction process was greatly influenced by the interactions between metal sites and sulfide species, directly influencing the OER performances of the reconstructed catalysts.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Yu-Xue Mo,Jin-Xia Lin,Yi-Jin Wu,Zu-Wei Yin,Yan-Qiu Lu,Jun-Tao Li,Yao Zhou,Tian Sheng,Ling Huang,Shi-Gang Sun
Rechargeable lithium–sulfur batteries are potential candidates for storing electrochemical energy because of their extremely high energy density. However, their practical applications are prohibited by the sluggish charge transfer, the retarding Li ion diffusion, and the shuttle effect of lithium polysulfides. We report here a high-performance cathode material in which a S submicrosphere with a mass fraction of 80% was encapsulated within a permeable Co(OH)2 nanoshell which functions as a physical barrier preventing the sulfur and polysulfides from leaking into the electrolyte and also contributes to the catalytic decomposition of polysulfides during the charge and discharge process. When an interlayer of carbon nanofibers is introduced between the S@Co(OH)2 cathode and the separator, the performance of the Li–S batteries can be further significantly enhanced. Specifically, the S@Co(OH)2 cathode possesses good cycling stability over 1000 cycles with an initial discharge capacity of 1100 mAh g–1 at 2 C and a reversible capacity of 606 mAh g–1. In particular, without the LiNO3 additive, this S@Co(OH)2 cathode also exhibits a Coulombic efficiency as high as 85%, just a little lower than that of commercial electrolyte with LiNO3 additive. Relevant mechanistic studies revealed that such superior performances are attributed to the enhanced internal electrical and ionic conductivity and suppressed shuttling effect, owing to the presence of the Co(OH)2 shell and the carbon-nanofiber interlayer. Theoretical simulations based on density functional theory were also carried out to figure out the interaction between the Co(OH)2 nanosheets and the polysulfides. It revealed that the Co(OH)2 nanoshell, rather than merely working as a physical barrier to trap the polysulfides, could also adsorb polysulfides and catalyze their decomposition during the cycling process, further helping to suppress the shuttling effect.
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Na Li,ChunYi Zhi,Haiyan Zhang
The preparation of high specific-capacity pseudocapacitive transition-metal-oxide/hydroxide (TMH) materials into transparent micro-structure electrodes is a great challenge and has become the bottleneck restricting the performance of transparent flexible supercapacitors . Beyond that, extending the operating voltage window is an urgent need for improving energy density . Here, Co(OH) 2 nanosheets and amorphous FeOOH nanowires were prepared into transparent films through a simple and scalable bio-inspired method at the air-solution interface. Both nanostructures are enwrapped in graphene shells (Co@Gr-TFandFe@Gr-TF) for use as transparent asymmetric pseudocapacitive electrodes. The unique encapsulation structures (1) provide pseudocapacitive electrode materials, especially an amorphous FeOOH structure cathode, (2) build up rapid three-dimensional electron and ion transport pathways together with the underlying ITO layer, (3) alleviate the exfoliation and dissolution of the active materials into electrolyte, and (4) extend the potential window of the FeOOH cathode from −0.8 ∼ 0 V to −1.2 ∼ 0 V with minimal cycling stability degradation. The asymmetric transparent and flexible supercapacitor based on Co@Gr-TF//Fe@Gr-TF operated at 1.8 V exhibits good transparency (50.5% at 550 nm), high specific capacitance (25.5 mF cm −2 , one order higher than the maximum value reported for FFT-GP), and high energy density (1.04 mWh cm −3 , comparable to that of nontransparent devices) as well as a long cycle life (10 000 cycles) with high-capacity retention (83.5%).
研究领域:
材料科学
·
纳米科技
·
电化学
·
能源存储
·
柔性电子学
·
功能薄膜
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）