CHEMICAL ENGINEERING SCIENCE
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2022
·
IF 4.889
Yuehua Deng,Wenhao Deng,Wenquan Huang,Zhiyong Zheng,Rui Zhang,Shiyuan Liu,Yanbin Jiang
Amorphization technology has been a promising strategy to improve the solubility and dissolution of drugs. This study aims to prepare norfloxacin (NFX) co-amorphous (CA) systems and evaluate the association between molecular descriptors and the formation and physical stability of NFX CAs. The molecular miscibility between NFX and 17 co-former candidates was firstly predicted using Hansen solubility parameters (HSPs) and six NFX CAs were successfully prepared by dry ball mill. Compared with crystalline NFX, four NFX CAs showed enhanced solubility (up to 2.50-fold) and dissolution rates. NFX CAs exhibited excellent physical stability under dry conditions. According to the quantitative calculations of Pearson correlation coefficient and Ridge regression, molecular descriptors have a great effect on NFX CA formation with structural parameters (Weight, VDW_vol, VDW_area, Rings) stronger than miscibility parameter Δ δ ¯ and p K a. These molecular descriptors corresponding to π···π interactions, molecular miscibility and ionic interactions are also responsible for physical stability. The results demonstrate that NFX CA can be stably formed if the co-former has more rings, smaller Δ δ ¯ (less than or close to 5 MPa 0.5 ) and larger Δp K a. This study offers a potential strategy to screen and design a CA system using multivariate data analysis based on theoretical considerations of molecular descriptors.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Lixia Wang,Jia Huang,Zhiyang Huang,Huatong Li,Tayirjan Taylor Isimjan,Xiulin Yang
Metallic defects can improve catalysts' intrinsic activity by regulating its electronic structure and enhancing conductivity. However, the impact of these defects on the kinetics of the oxygen evolution reaction (OER) has not been extensively studied. Here, a V/P codoped nanoflower-like CoS 2 catalyst with rich Co defects on carbon cloth (V,P-CoS 2 /CC) is fabricated by feasible directional construction. The V,P-CoS 2 /CC validates extraordinary OER performance with overpotentials of 227/300 mV at 10/100 mA cm −2 and robust long-term stability. The enhanced single-electron spin resonance signal and higher lifetime strength indicate an increased number of surface Co defects induced by V/P codoping. Density functional theory (DFT) calculations verify that Co defects induced by V/P codoping of the surface reconstituted V-CoOOH/CoS 2 catalyst can optimize the adsorption/desorption energy of oxygen-containing intermediates to accelerate OER process. Besides, the nanoflower-like morphology with large electrochemical active surface area and good hydrophilicity facilitates electrolyte diffusion/gas emission, thereby synergistically elevating OER performance.
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CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yanwei Zhu,Lang Gan,Jianqiao Shi,Gen Huang,Hongmei Gao,Li Tao,Shuangyin Wang
The structural design and atomic adjustment of the catalyst are the main factors that regulate the intrinsic electrocatalytic activity. Herein, we report a novel and facile strategy of synthesizing three-dimensional porous carbon network by polymer-assisted molding strategy. The porous carbon framework with Co-CoF 2 and carbon nanotubes (PCF@CCFCNT) was directly obtained by the calcination, in which Co-CoF 2 heterojunctions uniformly dispersed in the interconnected holes. Benefiting from the special hierarchical porous morphology, the dual-function catalytic activity of Co-CoF 2 heterojunctions and existence of Co-N x species, the as-obtained PCF@CCFCNT composites exhibit excellent performance in the oxygen evolution reaction (η = 300 mV@10 mA cm −2 ), as well as outstanding oxygen reduction reaction performance in alkaline medium (E 1/2 = 0.852 V, vs RHE). Moreover, as an air electrode in Zn-air batteries (ZABs), PCF@CCFCNT demonstrates a large peak power density of 184 mW cm −2 and superior long-term stability, which is much more stable than the one consisting of commercial Pt/C. This finding not only shows a simple composite design to achieve high-performance ZABs but also may stimulate the rapid development of 3D hierarchical porous electrocatalysts for advanced energy technologies.
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SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Xiaodan Zhao,Jiahui Wei,Ying Wu,Zuoming Zhou,Guohua Jing
Sulfite autoxidation in combination with the cobalt-based heterogeneous activators, has recently emerged as the efficient sulfate radical (SO 4 •− ) generation process for organic micropollutant abatement in the water and wastewater treatment , yet the sluggish >Co(II)/Co(III) redox cycling currently compromises the efficacy of radical generation and the potential applications. Herein, regarding that the reductive W(IV) species in WS 2 can modulate the >Co(II)/Co(III) redox cycling in the advanced oxidation processes , confinement of cobalt with WS 2 (Co-WS 2 ) is designed and characterized. The Co-WS 2 /sulfite process achieves an ultrafast tetracycline (TC) abatement (∼100 % abatement of TC within 1 min) under circumneutral conditions with lower dosage of sulfite and activator, outperforming the current cobalt-based heterogeneous counterparts. The dominant reactive radicals are identified as SO 4 •− and hydroxyl radical (HO • ), which are quantified to be 9.7 μM and 4.5 μM, respectively. The superior radical generation efficiency and the concomitant TC abatement rely on the excellent redox properties and electron transfer capability of Co-WS 2 . The inter-transformation of >Co(II)/>Co(III) can be accelerated via the involvement of the reductive W(IV) species with the redox-reversibility of the W(IV)/W(VI) couple in the presence of sulfite. The TC degradation intermediates and the corresponding pathways are also proposed according to the ultra-performance liquid chromatography and quadrupole-time of flight mass spectrometry (UPLC-QTOF-MS) analysis. In addition, the influences of the reactant dosage, coexisting anions (HCO 3 − , HPO 4 2− , Cl − and NO 3 − ), humic acid and the various real water matrices on TC abatement are thoroughly explored. Especially, the Co-WS 2 /sulfite process is advantageous owing to the negligible effect of the coexisting anions on the TC abatement. This study provides a novel heterogeneous activator for significantly improving sulfite activation efficacy to achieve the efficient organic micropollutant abatement.
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JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Shiyong Xu,Mei Li,Yijun Wang,Caiyun Gao,Rongsheng Xu,Zhiliang Jin
A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots (NSCQDs) nanoparticles on the surface of sheet cobalt-based metal-organic framework (Co-MOF) and graphitic carbon nitride (g-C 3 N 4 , CN). The structure and properties of the obtained catalysts were systematically analyzed. NSCQDs effectively broaden the absorption of Co-MOF and CN in the visible region. The new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254 μmol/(g·h) at pH = 9. At the same time, NSCQDs synergy Co-MOF/CN composites have good stability. After four cycles of hydrogen production, the performance remains relatively stable. The transient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite catalysts. The semiconductor type (n-type semiconductor) of the single-phase catalyst was determined by the Mott-Schottky test, and the band structure was analyzed. The conductive and valence bands of CN are −0.99 and 1.72 eV, respectively, and the conduction and valence bands of Co-MOF are −1.85 and 1.33 eV, respectively. The mechanism of the photocatalytic reaction can be inferred, that is, Z-type heterojunction is formed between CN and Co-MOF, and NSCQDs was used as cocatalyst.
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JOURNAL OF POWER SOURCES
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2023
·
IF 9.2
Gonghe Tong,Yanbin Li,Zhigang Wang,Xiaoyao Tan
Micro-tubular protonic ceramic fuel cells (MT-PCFCs) are prominently advantageous in energy conversion and storage , such as intermediate operating temperature, large volumetric power density, and low sealing requirements. Formation of thin and dense electrolyte film and efficient current collection, particularly from the micro lumen, are the primary challenges for preparing high-performance MT-PCFCs. The present work carries out a one-step fabrication of triple-layer hollow fibers (TLHFs) with anodic current collector/graded anode/electrolyte using BaCe 0 · 7 Zr 0 · 1 Y 0 · 2 O 3-δ via the phase-inversion based co-spinning/co-sintering technique. A BaCo 0 · 4 Fe 0 · 4 Zr 0 · 1 Y 0 · 1 O 3-δ based porous cathode is then applied on the TLHF's outer surface to create a complete fuel cell. The resultant single MT-PCFC yields a peak power density of 601.2 mW cm −2 at 700 °C. Furthermore, an MT-PCFC stack is made by bundling seven TLHFs using the porous cathode. With an effective area exceeding 12 cm 2 , the MT-PCFC stack generates a power output of 2.5 W at 700 °C. The stability test lasts for 100 h at 600 °C under 100 mA cm −2 and for next 60 h at varied temperatures from 700 to 600 °C under 200 mA cm −2 . The inventive design of TLHFs facilitates the scale-up of fuel cells, promoting the development of a large-scale MT-PCFC stack or systems.
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JOURNAL OF THE ENERGY INSTITUTE
·
2020
·
IF 4.748
Min Wang,Shupeng Guo,Ming Xia,Jungang Wang,Zhongyi Ma,Bo Hou,Litao Jia,Debao Li
Whether Co-ZrO 2 interfacial sites have a beneficial effect on Co-based Fischer-Tropsch synthesis is still controversial. In this paper, different quantities of Co-ZrO 2 interfacial sites were fabricated by changing the impregnation sequence of Zr added to Co/SiC catalysts. The effect of the Co-ZrO 2 interfacial sites was investigated by nitrogen adsorption, X-ray diffraction (XRD), hydrogen chemisorption (H 2 -TPD), temperature-programmed reduction (H 2 -TPR) and TEM-EDS- mapping analyses. It was found that when zirconium was on the surface of cobalt, more Co-ZrO 2 interfacial sites were formed, and a higher selectivity of long-chain hydrocarbons was observed. In addition, the formation of Co-ZrO 2 interfacial sites significantly increased the conversion frequency of CO. This work is of great significance for understanding the role of Co-ZrO 2 interfacial sites and guiding the design of related catalysts in Co-based Fischer-Tropsch synthesis.
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JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2018
·Vol. 86
·期 3
·699-710
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IF 1.745
Guo Jiuli,Han Qiuwan,Zhong Siyuan,Zhu Baolin,Huang Weiping,Zhang Shoumin
The M-modified TiO 2 nanotubes (NTs) (M = Ce, Ga, Co, Y, 2.0 wt%) were synthesized by combining sol-gel method with hydrothermal treatment, based on which gold was loaded by the deposition–precipitation approach. These catalysts were loaded with 1.5 wt% gold and calcined at 300 °C, and their catalytic performance was compared with Au/TiO 2 NTs in CO oxidation. TEM results manifested Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y) had smaller gold nanoparticles than Au/TiO 2 NTs. Patterns of XPS revealed the presence of the strong interaction between gold and support in Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y). Ce 4+ , Ga 3+ , Co 2+ , and Y 3+ ions were present as CeO 2 , Ga 2 O 3 , CoO, and Y 2 O 3 in Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y), respectively. Based on O 2 -TPD studies, Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y) provided new O 2 adsorption sites for the adsorption and activation of oxygen in CO oxidation. M (M = Ce, Ga, Co, Y) modifying performed the positive effect on CO oxidation activity and Au/Y-TiO 2 NTs showed the highest activity among these catalysts. Additionally, Au/Y-TiO 2 NTs also performed excellent high-temperature stability. It was likely that the strong interaction between gold and support created the small size of gold nanoparticles, large O 2 adsorption and plenty of defects, thereby enhancing the catalytic activity of Au/M-TiO 2 NTs (M = Ce, Ga, Co, Y).
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CHEMISTRY-A EUROPEAN JOURNAL
·
2018
·Vol. 24
·期 34
·8596-8602
·
IF 5.16
Yong Xu,Jiang Mo,Zi-Cheng Fu,Su Liu,Zhi Yang,Wen-Fu Fu
Graphical A hybrid photocatalyst consisting of Co and Co 2 P nanoparticles embedded in N, P-codoped carbon nanosheets was used in a visible light-driven system for CO 2 -to-CO conversion. The catalytic system displayed a high CO production rate of up to 35 000 μmol h −1 g −1 with CO selectivity of 79.1 % in the first 3 h of reaction. Linear CO production at an exceptionally high rate of 63 000 μmol h −1 g −1 was observed in the first 1 h of photocatalytic reaction. Artificial photosynthesis has attracted wide attention, particularly the development of efficient solar light-driven methods to reduce CO 2 to form energy-rich carbon-based products. Because CO 2 reduction is an uphill process with a large energy barrier, suitable catalysts are necessary to achieve this transformation. In addition, CO 2 adsorption on a catalyst and proton transfer to CO 2 are two important factors for the conversion reaction, and catalysts with high surface area and more active sites are required to improve the efficiency of CO 2 reduction. Here, a visible light-driven system for CO 2 -to-CO conversion is reported, which consists of a heterogeneous hybrid catalyst of Co and Co 2 P nanoparticles embedded in carbon nanolayers codoped with N and P (Co-Co 2 P@NPC) and a homogeneous Ru II -based complex photosensitizer. The average generation rate of CO of the system was up to 35 000 μmol h −1 g −1 with selectivity of 79.1 % in 3 h. Linear CO production at an exceptionally high rate of 63 000 μmol h −1 g −1 was observed in the first hour of reaction. Inspired by this highly active catalyst, Co@NC and Co 2 P@NPC materials were also synthesized and their structure, morphology, and catalytic properties for CO 2 photoreduction were explored. The results showed that the nanoparticle size, partially adsorbed H 2 O molecules on the catalyst surface, and the hybrid nature of the systems influenced their photocatalytic CO 2 reduction performance.
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PubMed
高影响因子
SURFACE AND INTERFACE ANALYSIS
·
2014
·Vol. 47
·期 2
·270-277
·
IF 1.393
Yongli Shi,Suying Ma,Ruiqiong Tian,Yingge Zhao,Qian Jiao,Xu Ma,Qing Shang
A novel amphiphilic copolymer was synthesized from poly (ethylene glycol) methyl ether methacrylate (PEGMA950), methyl methacrylate (MMA) and acryloyl- β -cyclodextrin (acryloyl- β -CD) using the composites of (NH 4 ) 2 S 2 O 8 /NaHSO 3 as the oxidation–reduction initiators. The successful fabrication of poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers was confirmed by Fourier transform infrared spectrometer (FTIR), 1 H-nuclear magnetic resonance ( 1 H NMR) spectra. The amphiphilic copolymer could self-assemble into nanoparticles (NPs), and their morphology and particle size distribution were characterized with transmission electron microscopy (TEM), atomic force microscope (AFM) and dynamic light scattering (DLS) methods. Ibuprofen (IBU) was encapsulated in the novel NPs, and the release profiles of IBU were investigated. FTIR and 1 H NMR spectra illustrated that the poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers were synthesized without any residual monomers and initiators. TEM and AFM photographs suggested that the obtained NPs were spherical, and the DLS results indicated that the diameter of blank NPs was 157.3 ± 32.7 nm. The IBU release profile showed that the IBU-loaded NPs had certain pH responsibility. Copyright © 2014 John Wiley & Sons, Ltd.
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JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 15
·
IF 1.866
Shuangbao Peng,BinShuang Wu,Linbo Wu,Bo-Geng Li,Philippe Dubois
It is indispensable to investigate hydrolytic degradation behavior to develop novel (bio)degradable polyesters. Biobased and biodegradable copolyesters poly(butylene adipate- co -butylene furandicarboxylate) (PBAF) and poly(butylene succinate- co -butylene furandicarboxylate) (PBSF) with BF molar fraction (ϕ BF ) between 40 and 60% were synthesized in this study. The hydrolytic degradation of film samples was conducted in a pH 7.0 PBS buffer solution at 25 °C. Slight mass loss (1–2%) but significant decrease in intrinsic viscosity (35–44%) was observed after 22 weeks. The apparent hydrolytic degradation rate decreased with increasing ϕ BF and initial crystallinity. Meanwhile, PBAFs degraded slightly faster than PBSFs with the same composition. The ϕ BF and crystallinity increased slowly with degradation time, suggesting the aliphatic moiety and the amorphous region are more susceptible to hydrolysis. And high enough tensile properties were retained after hydrolysis degradation, indicating PBAF and PBSF copolyesters are hydrolytically degradable, with tunable hydrolytic degradation rate and good balance between hydrolytic degradability and durability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44674.
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Nanoscale
·
2017
·Vol. 9
·期 29
·10233-10239
·
IF 7.367
Yanli Niu,Xiaoqin Huang,Xiaoshuai Wu,Lei Zhao,Weihua Hu,Chang Ming Li
Exploration of sustainable electrocatalysts toward oxygen reduction reaction (ORR) with high catalytic activity remains a key challenge in the development of metal–air batteries and fuel cells. In this work, a hybrid electrocatalyst composed of cobalt (Co/CoOx) nanoparticles encapsulated in Co/N-doped mesoporous graphene (Co/CoOx@Co/N-graphene) is reported for efficient ORR catalysis. The catalyst is rationally designed and synthesized via a facile combination of spontaneous one-pot polymerization of dopamine in the presence of graphene oxide (GO) and Co2+ ions and the subsequent carbonization process. The morphology, doping nature and ORR activity of the as-prepared catalyst are systematically investigated. It is found that there are abundant Co/N active sites and Co/CoOx nanoparticles in this hybrid catalyst, leading to a synergistic enhancement effect for improved ORR activity. In an alkaline environment, this Co/CoOx@Co/N-graphene catalyst displays Pt/C-comparable ORR activity in terms of half-wave potential and four-electron reduction selectivity, and higher limiting current density, better methanol tolerant ability and long-term durability. When being evaluated in a Zn–air battery, it demonstrates superior performance to the commercial Pt/C catalyst.
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