FUEL
·
2014
·
IF 3.406
Wenqing Li,Liying Wang,Yu Qiao,Jian-Ying Lin,Meijun Wang,Liping Chang
Understanding the effect of the atmosphere on the release of alkali and alkaline-earth metals (AAEM) during oxy-fuel combustion is important for the development of oxy-fuel combustion technologies with reduced problems with particulate formation and corrosion. To this end, we examined the release behavior of AAEM during oxy-fuel combustion in different gas environments. A drop-tube reactor and ion chromatography were used to investigate the release rates of AAEM. Our results show that the release rates of Na and K were higher than those of Ca and Mg in all types of gas environments. Experimental conditions that favor combustion, namely, higher temperature, higher oxygen content, and longer residence time, markedly increased the release rates of Na and K, whereas changes in the release rates of Ca and Mg were much smaller. The presence of SO 2 in the atmosphere suppressed the release of AAEM via formation of sulfates, whereas the presence of H 2 O promoted it. A synergistic effect of H 2 O and SO 2 on the release of AAEM during oxy-fuel combustion was observed.
研究领域:
燃烧化学
·
能源工程
·
环境化学
·
材料腐蚀
·
颗粒物形成
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Ke Wang,Zhaobin Tian,Na Yin
Novel cross-flow disturbance of ceramic membrane was used for the first time to enhance the adsorption of highly toxic Cu(II) onto Zr-based metal–organic frameworks (Zr-MOFs). Effects of temperature and pH were investigated on the adsorption process of Cu(II) onto the MOFs using the jar test. The results showed that the MOFs can well adsorb Cu(II) (59.8 mg g–1) at a pH of 6 and a temperature of 40 °C. On the basis of this, the MOFs were then added into a novel cross-flow ceramic membrane filtration system. Effects of the operation temperature and membrane pore size were also investigated on the adsorption process. The results showed that Zr-MOFs adsorption of Cu(II) increased with temperature. The ceramic membrane with a pore size of 200 nm exhibited better Cu(II) removal and membrane flux than did the 50 nm membrane, as well as better kinetic data fit of the pseudo-second-order model. With the aid of cross-flow disturbance of ceramic membrane, the capacity was incredibly increased to 988.2 mg g–1 at a pH of 6, temperature of 40 °C, cross-flow velocity of 4.5 m s–1, and trans-membrane pressure of 0.05 MPa. The principal advantages of this method are a significant enhancement of adsorption onto the Zr-MOFs in the removal of Cu(II) and convenient application in the continuous treatment of heavy metal wastewater. This can be used as an effective method in continuous adsorptive removal of heavy metals from wastewater.
研究领域:
环境科学
·
材料科学
·
化学工程
·
水处理技术
·
吸附分离
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Weiji Dai,Tao Lu,Ye Pan
Efficient oxygen evolution reaction catalysts based on earth-abundant and low-cost elements are urgently required for water splitting devices and metal-air batteries . Herein, for the first time we report a novel and promising MO x (M = Mn, Fe, Co and Ni) nanosheets catalyst for oxygen evolution reaction based on the MnFeCoNi high entropy alloy . By an electrochemical cyclic voltammetry scan activation, the MO x nanosheets can grow directly on the MnFeCoNi high entropy alloy particle surfaces forming a core-shell structure. The core-shell structure exhibits a low overpotential of 302 mV to achieve current density of 10 mA cm −2 , a small Tafel slope of 83.7 mV dec −1 and exceptional long-term stability of electrolysis for over 20 h in 1 M KOH alkaline solution, which is comparable to the state-of-the-art oxygen evolution reaction electrocatalyst RuO 2 . We make an investigation of the MnFeCoNi high entropy alloy before and after cyclic voltammetry scan activation on their morphologies, chemical states and elements composition to understand the materials evolution. The present work not only provides a promising electrocatalyst but also broadens the application areas of high entropy alloys.
研究领域:
材料科学
·
电化学
·
能源化学
·
纳米科技
·
催化化学
✓ 已验证
DOI
高影响因子
National Science Review
·
2024
·
IF 16.3
Cheng Han,Gui Renjie,Chen Chen,Liu Si,Cao Xuemin,Yin Yifan,Ma Ruize,Wang Wenjie,Zhou Tianpei,Zheng Xusheng,Chu Wangsheng,Xie Yi,Wu Changzheng
Platinum-based intermetallic compounds (IMCs) play a vital role as electrocatalysts in a range of energy and environmental technologies, such as proton exchange membrane fuel cells (PEMFCs). However, the synthesis of IMCs necessitates recombination of ordered Pt-M metallic bonds with high temperature driving, which is generally accompanied by side effects for catalysts’ structure and performance. In this work, we highlight that the semimetal atoms can trigger covalent interactions to break synthesis-temperature limitation of platinum-based intermetallic compounds and benefit for fuel-cell electrocatalysis. Attributed from partial fillings of p-block in semimetal elements, the strong covalent interaction of d-p π backbonding can benefit the recombination of ordered Pt-M metallic bonds (PtGe, PtSb and PtTe) in the synthesis process. Moreover, this covalent interaction in metallic states can further promote both electron transport and orbital fillings of active sites in fuel cells. The semimetal-Pt IMCs were obtained with a temperature 300 K lower than that needed for the synthesis of metal-Pt intermetallic compounds and reached the highest CO-tolerant oxygen reduction activity (0.794 A mg−1 at 0.9 V and 5.1% decay under CO poisoning) among reported electrocatalysts. We anticipate that semimetal-Pt IMCs will offer new insights for rational design of advanced electrocatalysts for fuel cells.
研究领域:
材料科学
·
能源科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2017
·
IF 3.473
Yijun Zhang,Jiaqi Zhang,Junwen Zhang,Sai Lin,Yunyun Huang,Rongrong Yuan,Xiaojuan Liang,Weidong Xiang
A novel gold-carbon dots (GCDs) exhibiting relatively high luminescence have been successfully synthesized by a facile solution cast method. Intriguingly, colloidal Au nanoparticles (Au NPs) present an enhancement effect on the photoluminescence of CDs, which can be attributed to the metal enhanced fluorescence (MEF) included two cooperative mechanisms and near-field interactions. Significantly, the 1.5–3 fold enhancement was obtained in the vicinity of Au NPs. The formation mechanism and chemical structure of the as-prepared GCDs were verified by a series of characterization techniques, such as high-resolution transmission electron microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The GCDs with optimal fluorescence was acquired by varying volume ratio of colloidal Au NPs to CDs, rendering bright visible light under 460 nm excitation and high quantum yield (QY) of 39%. Given that, a simple spin coating technology was developed for fabricating GCDs film composed of GCDs solution and quartz glass. Subsequently, GCDs-based white light emitting diodes (white LED) was designed through integrating blue LED chips with the yellow light-emitting GCDs film. In addition, the GCDs film at appropriate thickness possesses excellent optical performances with the corresponding optimized color coordinate (CIE) of (0.33, 0.36), the color rendering index (CRI) of 78.2, correlated color temperature (CCT) of 5653 K, and the luminous efficiency (LE) approaching to 43.75 lm W −1 . These superior results demonstrate that GCDs constitute a versatile and effective route for achieving high-performance white LED.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2021
·
IF 9.811
Zhongnan Guo,Fan Sun,Danilo Puggioni,Yubo Luo,Xiaotong Li,Xiuquan Zhou,Duck Young Chung,Erjian Cheng,Shiyan Li,James M. Rondinelli,Wenxia Yuan,Mercouri G. Kanatzidis
Metal cluster compounds have garnered renewed interest in the search for novel superconductors and topological semimetals owing to structural instabilities of metal-cluster geometries and broken symmetries. Here we synthesized needle-like crystals of the V-cluster-based quasi-one-dimensional (Q1D) materials AV3Q3Oδ (A = K, Rb, Cs, Q = Se, Te) which can also be viewed as being composed of parallel nanowires. We examine how changes in their average and local structure control their electronic properties. All compounds crystallize in the TlFe3Te3-type structure (P63/m space group) with infinite (V3Q3)− double-walled columnar chains separated by A+ cations. Our single-crystal and synchrotron powder diffraction studies indicate oxygen atoms partially occupy the center site of the V6 octahedral metal cluster cages in KV3Te3O0.33, RbV3Te3O0.32, and CsV3Te3O0.35, whereas KV3Se3 is structurally oxygen-free. Our synchrotron X-ray pair distribution function (PDF) analyses indicate that the oxygen-free V6 cluster octahedra in KV3Se3 are highly distorted perpendicular to the chain direction even at room temperature, reducing the symmetry of the average structure from hexagonal P63/m to monoclinic P21/m. Our theoretical calculation supports this P21/m distortion and suggests the structure further distorts to P21 or P21/c at lower temperatures. In contrast, the oxygen-centered V-cluster in KV3Te3O0.33 exhibits a V3-triangle-trimerization along the chain direction. This feature is discernible from the local PDF and is consistent with lattice dynamical calculations based on density functional theory. Resistivity measurements indicate that KV3Se3 exhibits metallic behavior, whereas a dramatic metal–semiconductor–metal transition emerges in KV3Te3O0.33, RbV3Te3O0.32, and CsV3Te3O0.35 because of oxygen disorder and changes in local structure captured from our electronic structure analyses of the Fermi surface. Our investigation of the AV3Q3Oδ family demonstrates the importance of understanding local changes in structure driven by electronic instabilities, which can guide the search for new quantum materials in other low-dimensional cluster-compound materials.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Shujun Liu,Xiaofei Chen,Zhikuan Wang,Yi Yu,Yongsheng Huang,Jiajun Zeng,Yuxuan Lin,Chongxiong Duan,Hongxia Xi
The design and fabrication of novel two-dimensional (2D) metal-organic framework (MOF) nanosheets with excellent electrochemical performance are significant in the field of energy storage. Herein, a series of 2D bimetallic nickel‑cobalt MOFs (NiCo-MOFs) nanosheets based on thiophene ligand with adjustable components are synthesized using an in situ approach and a facile one-step hydrothermal reaction in DMF/H 2 O mixed solvent. These thienyl based NiCo-MOF nanosheets, grown directly on nickel foam (NF), function as electrodes for supercapacitors . The optimal NiCo-MOF/NF-3-2 (Ni/Co = 3:2) obtained by modulating the Ni/Co molar ratio demonstrates an ultrahigh specific capacity of 615.7 C g −1 (1243 F g −1 ) at the current density of 1 A g −1 and an excellent rate capacity (63.9% retention at 10 A g −1 ). DFT calculations indicate that adjustable bimetallic composition can modulate the electronic structure of metal centers and improve conductivity of MOF materials. The exceptional electrochemical performance of the NiCo-MOF/NF-3-2 electrode can be attributed to regular 2D nanosheet arrays on a conductive substrate, which provides open spaces and short transport distance between abundance active sites and electrolyte ions. Moreover, an asymmetric supercapacitor device composed of NiCo-MOF/NF-3-2 and active carbon exhibits a high energy density of 54.6 Wh kg −1 at a power density of 800 W kg −1 and an outstanding cycle life with a capacitance retention of 84.7% after 5000 cycles. This study demonstrates the remarkable potential of novel 2D bimetallic NiCo-MOF nanosheets for energy storage and conversion applications.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2017
·
IF 3.833
Liwei Dai,Liping Song,Youju Huang,Lei Zhang,Xuefei Lu,Jiawei Zhang,Tao Chen
Due to the larger surface area and the synergistic effects between two noble metals, the bimetallic superstructures exhibit enhanced distinctive optical, catalytic, and photothermal performances and surface-enhanced Raman scattering (SERS) “hot-spot” effect, and thus have attracted great interest in various applications. Compared with the common Pd, Pt hierarchical structures coated onto Au nanoparticles (NPs), easily synthesized via fast autocatalytic surface growth arising from intrinsic properties of Pd and Pt metals, precisely controlling the hierarchical Ag growth onto Au NPs is rarely reported. In our present study, the reducing agent dopamine dithiocarbamate (DDTC) was covalently capped onto the first metal core (Au) to delicately control the growth model of the second metal (Ag). This results in heterogeneous nucleation and growth of Ag precursor on the surface of Au nanorods (NRs), and further formation of cornlike bimetallic Au/Ag core–shell superstructures, which usually cannot be achieved from traditional epitaxial growth. The thickness of the hierarchical Ag shell was finely tuned in a size range from 8 to 22 nm by simply varying the amount of the ratio between Ag ions and DDTC capped on Au NR core. The tunable Ag shell leads to anisotropic bimetallic Au/Ag core–shell superstructures, displaying two distinctive plasmonic resonances in the near-infrared region (NIR). In particular, the longitudinal surface plasmon resonance exhibits a broadly tunable range from 840 to 1277 nm. Additionally, the rich hot spots from obtained Au/Ag superstructures significantly enhance the SERS performance.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 24
·9628-9633
·
IF 3.069
Alam Venugopal Narendra Kumar,Shuli Yin,Ziqiang Wang,Xiaoqian Qian,Dandan Yang,You Xu,Xiaonian Li,Hongjing Wang,Liang Wang
The shape-controlled synthesis of bimetallic Pt-based nanoarchitectonics has attracted considerable interest due to their remarkable electrocatalytic activity for the oxygen reduction reaction (ORR). In this work, we report a direct method for the fabrication of unique bimetallic AuPt nanobrick spherical nanoarchitectonics (AuPt NSNs) in aqueous solution. Benefiting from their rugged surfaces and bimetallic compositions, AuPt NSNs exhibit excellent electrocatalytic performance for the ORR. The proposed method is very useful for the fabrication of metallic nanoarchitectonics with rugged surfaces.
研究领域:
纳米材料学
·
电化学
·
催化化学
·
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Materials Today Energy
·
2020
·
IF 5.604
Ziqi Zhang,Linchuan Cong,Zhuochen Yu,Lina Qu,Weimin Huang
Hydrogen is one of the most desirable sources with large energy density . Electrocatalysis of hydrogen evolution reaction is a promising way to produce hydrogen since it can be powered by renewable energy such as solar and wind energy . However, the mainstream electrocatalyst is noble metal (Pt/Ru/Ir), which is expensive and rare. It is necessary to develop non-noble metal catalysts toward HER from the perspective of sustainable development and long-term environmental conservation. Therefore, this paper provides a cheap and feasible way to synthesize the Fe–Ni bimetallic N-doped carbon framework (Fe–Ni@NCF). The prepared Fe–Ni@NCF exhibits the desired overpotential of 219 mV at 10 mA cm −2 in alkaline and 259 mV at 10 mA cm −2 in acidic solution, respectively. Besides, it exhibits similar current density loss as commercial Pt/C after 10,000 segments of CVs, which suggests satisfactory durability.
研究领域:
材料科学
·
电化学
·
能源化学
·
催化化学
·
纳米材料
✓ 已验证
DOI
高影响因子
Nanoscale Research Letters
·
2013
·Vol. 8
·期 1
·1-8
·
IF 2.524
Jamal Ruxangul,Xu Feng,Shao Weiwei,Abdiryim Tursun
The solid-state method was applied for synthesizing polyaniline (PANI)/noble metal hybrid materials with the presence of HAuCl 4 ·4H 2 O or H 2 PtCl 6 ·6H 2 O in the reaction medium. The structure, morphology, and electrochemical activity of the composites were characterized by Fourier transform infrared (FTIR) spectra, UV-visible (vis) absorption spectra, energy dispersive spectrum (EDS), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and cyclic voltammetry. The results from FTIR and UV-vis spectra showed that the oxidation degree and doping level of the PANI in composites can be influenced by HAuCl 4 ·4H 2 O and H 2 PtCl 6 ·6H 2 O. The EDS data demonstrated that the composites contain a certain amount of Au (or Pt) element. XRD analysis indicated the presence of crystalline-state Au particles in PANI matrix prepared from the presence of HAuCl 4 ·4H 2 O and revealed that the H 2 PtCl 6 ·6H 2 O cannot be converted into metal Pt. The TEM and SEM images implied that the Au particles did exist in the polymer matrix with the size of about 20 nm. The enzymeless H 2 O 2 sensor constructed with PANI/Au composite from the presence of HAuCl 4 ·4H 2 O showed a short response time (within 5 s) and displayed an excellent performance in wide linear range.
研究领域:
材料科学
·
纳米科技
·
电化学
·
生物传感器
·
高分子化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2011
·Vol. 36
·期 23
·15266-15272
·
IF 4.057
Pei Pei Yuan,Bin Hong Liu,Zhou Peng Li
A comparative study was performed on four LiBH 4 -based hydrogen storage composites 2LiBH 4 + MgX 2 and 6LiBH 4 + CaX 2 (X = H and F). The composites with fluorides and those with corresponding hydrides exhibited similar hydrogen storage properties. The dehydrogenation of 2LiBH 4 + MgF 2 demonstrated a strong dependence on the hydrogen back pressure , similar to that of 2LiBH 4 + MgH 2 . The reversible hydrogen storage of 2LiBH 4 + MgF 2 was achieved under a back pressure of 5 bar at 450 °C. Dehydrogenation under lower H 2 pressures resulted in the production of Mg and thus a partial reversibility. In contrast, both 6LiBH 4 + CaH 2 and 6LiBH 4 + CaF 2 revealed reversible hydrogen storage properties regardless of the hydrogen back pressure. The structural difference between MgB 2 and CaB 6 may account for the observed differences in hydrogen storage properties of the Mg- and Ca-containing LiBH 4 reactive composites.
研究领域:
材料科学
·
能源化学
·
固态储氢
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）