ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Huan Wang,Yanming Liu,Zhonghua Sun,Jianhai Ren,Xiaoran Zou,Chun-Yang Zhang
Oxygen evolution reaction (OER) plays important roles in energy storage and conversion technologies, but the sluggish kinetics of OER may result in a large overpotential, and thus there is urgent need for the exploration of new electrocatalysts with a low overpotential and good stability. In this research, we integrate the melamine-assisted alkaline cobalt carbonate (CoCH) nanosheets pyrolysis with high-temperature solid phase fusion to construct the 1-C 3 N 4 /Co 3 O 4 /Ni foam hybrid electrode with Co 3 O 4 ultrathin porous nanosheets as the host, trace C 3 N 4 as the guest, and Ni foam (NF) as the current collector. Benefiting from the unique structure, the obtained 1-C 3 N 4 /Co 3 O 4 hybrid nanosheets can significantly reduce the charge transfer distance between the catalysts to electron collector and improve the electron transportation during the OER process. Moreover, the intimate interaction of Co 3 O 4 with C 3 N 4 can induce a charge redistribution at the interface. Consequently, the 1-C 3 N 4 /Co 3 O 4 /NF hybrid electrode exhibits an enhanced OER performance (166 mV at 10 mA•cm −2 ) and good stability, superior to the commercial RuO 2 particles and the reported transition metal-based electrocatalysts.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 9
·1571
·
IF 5.719
Hao Gong,Shiguang Bie,Jian Zhang,Xianbin Ke,Xiaoxing Wang,Jianquan Liang,Nian Wu,Qichang Zhang,Chuanxian Luo,Yanmin Jia
The Co3O4electrode is a very promising material owing to its ultrahigh capacitance. Nevertheless, the electrochemical performance of Co3O4-based supercapacitors is practically confined by the limited active sites and poor conductivity of Co3O4. Herein, we provide a facile synthetic strategy of tightly anchoring Co3O4nanosheets to a carbon fiber conductive cloth (Co3O4@C) using the zeolitic imidazolate framework-67 (ZIF-67) sacrificial template via in situ impregnation and the pyrolysis method. Benefiting from the enhancement of conductivity and the increase in active sites, the binder-free porous Co3O4@C supercapacitor electrodes possess typical pseudocapacitance characteristics, with an acceptable specific capacitance of ~251 F/g at 1 A/g and long-term cycling stability (90% after cycling 5000 times at 3 A/g). Moreover, the asymmetric and flexible supercapacitor composed of Co3O4@C and activated carbon is further assembled, and it can drive the red LED for 6 min.Keywords:ZIF-67;Co3O4nanosheet;in situ growth;Co3O4@C;supercapacitor
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2024
·
IF 8
Bing Song,Lixue Qi,Hongyi Wu,Yan Tong,Li Li,Muhammad Ikram,Keying Shi
The solvothermal and wet chemical method was developed to synthesized the p-n heterostructures of the thin porous Co 3 O 4 nanosheets with ZnO nanoparticles. The resulting products were analyzed by using various characterization techniques. The results possessed that the presence of a large number of oxygen defects on the surface of Co 3 O 4 -ZnO-7 favors enhancing the NO 2 adsorption. Correspondingly, the formation of p-n heterojunction and the large surface area of the material itself increased the carrier density and exposed more active sites, which collectively boost the sensing performance to NO 2 . The sensor showed a high response of 45.7 (S = R a /R g ) to 100 ppm NO 2 at room temperature (RT = 25 °C), with a short response/recovery time (1.3/25 s), and the lower detection limit of the sensor reached 30 ppb, with good selectivity, reproducibility and stability. This study will offer the opportunity to develop new sensors with high response and fast response-recovery to NO 2 at room temperature.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Zhen-Hong He,Yong-Chang Sun,Yuan-Yuan Wei,Kuan Wang,Weitao Wang,Zhuo Chen,Zhong-Yu Wang,Yue Tian,Zhao-Tie Liu
The reaction of methanol and CO 2 is an ideal route for the utilization of CO 2 resources and the synthesis of dimethyl carbonate (DMC), which is an important fuel and fuel-additive. In this work, we developed a catalyst of CeO 2 nanoparticles (CeO 2 NPs) loaded on Co 3 O 4 nanosheets (Co 3 O 4 NSs) with the Ce/Co molar ratio of 3/7 (Ce 3 -NPs/Co 7 -NSs) which could efficiently catalyze the reaction. The formation activity and the yield of DMC reached 16.8 mmol·g cat -1 ·h −1 and 47.2 % (based on methanol), surpassing most reported catalysts, especially at a relatively low temperature of 120 ℃. Characterization results indicated that the Co 3 O 4 NSs could enhance the amounts of oxygen vacancies and CO 2 adsorption but reduce methanol adsorption. The adsorption equilibrium between methanol and CO 2 is crucial for the titled reaction, and the in-situ IR spectra confirmed that the catalyst could simultaneously activate CO 2 and methanol and the reaction involves a Langmuir-Hinshelwood (LH) mechanism. The present strategy for constructing a catalyst of CeO 2 nanoparticles loaded on Co 3 O 4 nanosheets provides an efficient catalyst for the DMC synthesis from CO 2 and methanol and offers an important reference in building other catalysts with adjustable adsorption capacities of CO 2 and methanol.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2015
·
IF 6.723
Xiaoli Zhang,Jinbao Zhang,Kai Wang
Nanostructured Co3O4 doped with Zn2+, Ni2+, and both were directly grown on an ITO substrate by an easily available hydrothermal method. The doped Co3O4 showed a unique structural morphology evolution upon controlling the doping elements and the doping ratio of the cations. For the codoped samples, the novel rhombus-shaped Co3O4 nanosheets doped with Zn2+ and Ni2+ (concentration ratio of 1:2) exhibited the optimal electrocatalytic performance. The sample showed a current density of 165 mA cm–2 at 1.75 V, approximately 1.6 and 4 times higher than that of samples doped with Zn2+ and Ni2+ at a concentration ratio of 1:1 and 1:3. The unique architecture and its corresponding modified physical properties, such as high active-site density created by codoping, large structural porosity, and high roughness, are together responsible to its superior performance. For codoped Co3O4 nanostructures, Zn2+ facilitates the creation of Co cations in their high oxidation state as active centers, while Ni2+ contributed to the new active sites with lower activation energy. The synergistic effect of Zn2+ and Ni2+ doping can explain the improved physicochemical properties of codoped Co3O4 nanostructures.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Song Cheng,Yutao Liu,Xinyi Liu,Changqing Zhu,Jingyang Luo,Jiashun Cao,Fuqiang Liu
Electro-assisted activation of peroxymonosulfate (EA-PMS) by transition metals oxides (TMOs) has been extensively studied for the removal of organic pollutants. Despite TMOs possess considerable activity and affinity to PMS, their poor bulk conductivity still limits the electron exchange during the TM δ/δ+1 redox cycle, especially the efficient reduction of TM δ+1 via cathodic process. In this study, carbon felt loaded with modified Co 3 O 4 nanosheets (Co@FCF) was fabricated and applied as the flow-through electrode of EA-PMS process, where the Co 3 O 4 nanosheets were embedded with numerous metallic Ni particles encapsulated within carbon layers (Ni@C). Driven by weak electric current, continuous electrons can be supplied to the bulk Co 3 O 4 from the electron-rich Ni@C nanoparticles, resulting in accelerated Co 3+ /Co 2+ cycle, enhanced production of SO 4 ·− and improved energy utilization efficiency. Electrochemical tests along with density functional theory calculations indicate that the unique structure of Co@FCF played essential role in the enhanced performance.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Xinyang Wang,Rui Li,Xinyu Luo,Jincheng Mu,Jianbiao Peng,Guangxuan Yan,Pengkun Wei,Zhenbang Tian,Zuohua Huang,Zhiguo Cao
Enhancing low-temperature activity is a focus for carbon monoxide (CO) elimination by catalytic oxidation. In this work, the hierarchical flower-like silver (Ag) modified cobalt oxides (Co 3 O 4 ) nanosheets were prepared by solvothermal method and applied into catalytic CO oxidation. The doped Ag species in the form of AgCoO 2 induced the prolongated surface Co–O bond and weaker bond intensity. Consequently, the oxygen activation/migration ability and redox capacity of Ag 0.02 Co were enhanced with more oxygen vacancies. The chemisorbed CO was preferentially converted to CO 2 but not carbonates. The inhibited carbonates accumulation could avoid the coverage of active sites. According to Density functional theory (DFT) calculations, the electron transfer from AgCoO 2 to Co 3 O 4 promote electron donation ability of Co 3 O 4 layer, benefiting for oxygen activation. Moreover, the longer Co–C and C–O bond length suggest the weakened chemisorption strength and higher active of CO molecule. The Ag modified Co 3 O 4 exhibited more satisfactory activity at lower temperature. Typically, it realized 100% CO conversion at 90 °C, and displayed 6.3-fold higher reaction rate than pristine Co 3 O 4 at 40 °C. Moreover, the Ag 0.02 Co exhibited outstanding long-term stability and water resistance. In summary, the optimized oxygen activation, CO chemisorption and interfacial electron transfer synergistically boosted the CO oxidation activity on Ag modified Co 3 O 4 .
研究领域:
催化材料
·
环境科学
·
理论计算
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Xiaocong Qin,Qi Xue,Changluo Su,Yuan Dang,Xiaoqin Sun,Yuanzhen Zhou
Catalytic oxidation is an efficient method for mitigating toluene emissions, but enhancing catalytic performance for toluene oxidation remains a challenge. To enhance the oxidation capacity of catalysts, appropriate morphology and composition adjustments are required. Herein, the porous CeO 2 -Co 3 O 4 hybrid nanosheets (CeO 2 -Co 3 O 4 HNSs) have been designed and prepared by the hydrothermal method . Compared with single composition CeO 2 and Co 3 O 4 , the CeO 2 -Co 3 O 4 HNSs exhibit superior performance, achieving a remarkable 90% toluene conversion at a reaction temperature of 215°C with a space velocity of 36,000 mL/(h·g). Their enhanced activity can be attributed to the unique morphology and multi-component synergistic effect. The introduction of Co can significantly increase the content of oxygen vacancy and optimize the electronic structure, which can enhance the formation of surface-active oxygen and accelerate the cycle of the Ce 3+ /Ce 4+ redox pair. This work establishes a promising avenue for treating volatile organic compounds in exhaust emissions.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Jiayun Liu,Zhilin Li,Min Wang,Chongyue Jin,Jin Kang,Yiwu Tang,Siyan Li
In this study, Eu 2 O 3 /Co 3 O 4 nanosheets (NSs) were successfully synthesized and employed to degrade levofloxacin (LVX) via peroxymonosulfate (PMS) activation. Owing to the enhanced transfer efficiency of Co 2+ /Co 3+ and more adsorbed oxygen, the obtained Eu 2 O 3 /Co 3 O 4 NSs displayed better catalytic performance for PMS activation toward LVX degradation than pure Co 3 O 4 . The Eu 2 O 3 /Co 3 O 4 NSs can remove 97.93% of LVX only in 6 min via activating PMS, with a reaction rate constant (0.2346 min −1 ) , which was 2.3 folds of single Co 3 O 4 NSs (0.1003 min −1 ). Besides, Eu 2 O 3 /Co 3 O 4 exhibited good catalytic performance in presence of different inorganic anions, satisfactory stability and reusability. Singlet oxygen ( 1 O 2 ), hydroxyl radical (•OH), sulfate radical (SO 4 •− ) and superoxide radical (•O 2 − ) contributed to LVX degradation and 1 O 2 played the most key role. In addition, based on the ROSs and LVX degradation intermediates, the possible mechanism and degradation pathways of LVX were further cleared in detail. This work can provide a reference for the eco-friendly and facile preparation strategy of efficient and stable catalysts for rapid and efficient removal of recalcitrant pollutants.
研究领域:
环境科学
·
催化材料
·
污染治理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Wenping Wang,Manshu Zhang,Ruiyu Mi,Yangai Liu,Jian Chen
Nanosized cobalt (II, III) oxide (Co 3 O 4 ) is a promising anode material in virtue of its relatively high theoretical capacity. In this study, nanosized Co 3 O 4 was fabricated by facile hydrothermal method followed by annealing. So-obtained samples exhibited integrated characteristics and advantages including porous nanosheets structure, oxygen vacancy , and pseudocapacitance Pseudo-capacitance. The splendid electrochemical properties of Co 3 O 4 electrodes are inseparable from these features providing synergistic effect. During insertion and extraction of lithium ion , porous nanosheets structure not only assisted in buffering volume changes, but also benefitted the transportation of electron/ion. Furthermore, abundant oxygen vacancies improved internal conductivity and promoted migration of lithium ion via regulating surface electronic structure. The pseudocapacitance behavior was instrumental in electrochemical kinetics. Consequently, the resulting nanosized Co 3 O 4 delivered fine discharge specific capacity (1502.5 mAh g −1 ) after 100 cycles at 200 mA g −1 accompanied by the superior capacity retention rate (97.8%). Discharge specific capacity (1093.5 mAh g −1 ) higher than that of graphite, was recorded even at a current density of 2 A g −1 . The results indicate that the as-obtained MNS-CoO 1.0M with excellent properties may act as promising alternative candidates for lithium storage materials.
研究领域:
材料科学
·
电化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2018
·Vol. 410
·期 29
·7663-7670
·
IF 3.307
Liu Fuyan,Wang Peng,Zhang Qianqian,Wang Zeyan,Liu Yuanyuan,Zheng Zhaoke,Qin Xiaoyan,Zhang Xiaoyang,Dai Ying,Li Lu,Huang Baibiao
Novel porous Co 3 O 4 nanosheets (NSs) were synthesized on the flexible carbon cloth (CC) substrate by a facile hydrothermal method and applied to construct a non-enzymatic sensor for glucose detection. The sensor is based on the electro-catalytic oxidation of glucose on the surface of Co 3 O 4 NSs. Since this particular nanostructure can provide large surface area and more active sites, the Co 3 O 4 NSs non-enzymatic sensor exhibits excellent analytical performance, such as a high sensitivity (8506 μA mM −1 cm −2 ), a fast response time (less than 6 s), low detection limit of 1 μM, good selectivity, and long-term stability. The results suggest that the porous Co 3 O 4 NSs have great potential applications in the development of sensors for enzyme-free detection of glucose.
研究领域:
材料科学
·
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Tan Jingying,Geng Weifu,Li Junde,Wang Zhen,Zhu Shaohao,Wang Xiuzhong
The mimic enzyme has become a research hotspot in recent years because of its advantages of high stability, convenient preparation, and low price. In this article, Co3O4 nanosheets synthesized by a simple hydrothermal method possess the characteristics of a peroxidase-like activity. The results demonstrated that 3,3′,5,5′-Tetramethylbenzidine (TMB) could be oxidized by H2O2 to produce a typical blue product (oxTMB) which has a strong absorption at 650 nm wavelength with the help of the Co3O4 nanosheets. Thus, a simple and sensitive colorimetric detection method for H2O2 was established with a good linear relationship (2–200 μM) and a low limit of detection (0.4 μM). Meanwhile, the colorimetric product can effectively quench the fluorescence emitted by Ru(bpy)32+. Therefore, a colorimetric and fluorescence dual detection mode photochemical sensor for H2O2 detection is constructed based on the principle of the inner filter effect (IFE) between the colorimetric product (oxTMB) and Ru(bpy)32+. It can effectively avoid the false positive problem of a single detection mode. In the presence of glucose oxidase, glucose can be catalyzed to produce gluconic acid and H2O2; therefore, the sensor can also be used for the determination of glucose with a good linear relationship (0.02–2 μM) and a low limit of detection (5 nM). Experimental results showed that the sensor has a high sensitivity and strong anti-interference ability which can be used for the detection of actual samples.
研究领域:
生物传感器
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）