Inorganic Chemistry Frontiers
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2022
·Vol. 9
·期 9
·1956-1963
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IF 7.779
Mengen Gao,Qiang Bian,Hongping Wu,Hongwei Yu,Zhanggui Hu,Jiyang Wang,Yicheng Wu
Birefringent crystals, which can modulate the polarization of light, are particularly important in optical communication and the laser industry. Here we report the synthesis, structures, optical properties, and theoretical analyses of four rare-earth borates containing BO3 groups, i.e. LiRb2YB2O6, CaRbYB2O6, and Li2MY4B5O15 (M = Rb, Cs). Their structures are not all typical BO3 group distributions with large birefringence values, e.g., being parallel with each other's distribution or being a regular polygon distribution with a specific form that is parallel with an optical axis. However, their birefringence values exhibit an obvious increase from LiRb2YB2O6 (0.038@532 nm) to Li2MY4B5O15 (M = Rb, Cs) (0.103@532 nm). The origin of this birefringence increase was studied by structural analysis and theoretical calculation. First-principles calculations and structure comparisons indicate that the non-symmetry localization of electron density of the Y–O polyhedra has an important contribution to the large birefringence of Li2MY4B5O15 (M = Rb, Cs).
研究领域:
光学材料
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材料科学
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理论物理
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产品关联
DOI
高影响因子
Energy & Environmental Materials
·
2021
·Vol. 6
·期 1
·e12273
·
IF 15.122
Huanhuan Zhang,Ke Zhang,Saima Ashraf,Yanping Fan,Shuyan Guan,Xianli Wu,Yushan Liu,Baozhong Liu,Baojun Li
Boron hydrides release an abundant amount of hydrogen in the presence of a suitable catalyst. Accelerating bimolecular activation kinetics is the key to designing cost-effective catalysts for borohydride hydrolysis. In this study, the bimolecular activation of a polar O–Co–P site demonstrated superior hydrogen-generation kinetics (turnover frequency, TOF = 37 min −1 , 298 K) and low activation energy (41.0 kJ mol −1 ) close to that of noble-metal-based catalysts. Through a combination of experiments and theoretical calculations, it was revealed that the activated dangling oxygen atom in the Co–O precursor effectively replaced via surface-phosphorization because of strong electronic interactions between the dangling oxygen and P atoms. This substitution modulated the local coordination environment and electronegativity around the surface Co sites and formed a new polar O–Co–P active site for optimizing the activation kinetics of ammonia borane and water. This strategy based on bimolecular activation may create new avenues in the field of catalysis.
研究领域:
催化化学
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材料科学
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理论计算
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2022
·
IF 8.129
Wang Li,Wen-Ying Li,Xing-Bao Wang,Jie Feng
During direct coal liquefaction , selective C al –O bond cleavage is critical for phenol production. In this study, anisole and benzyl phenyl ether were chosen as the oxygen-containing model compounds. Radical-induced sites of benzyl phenyl ether were investigated using the Fukui function and energy barrier calculation. The promotion routes of the C al –O bond cleavage in anisole and benzyl phenyl ether by radicals were illustrated. The formation of o -benzyl phenol was regarded as a sign of benzyl radical-induced pyrolysis based on the most optimal path. The competitive process between the optimal path and β-bond scission path was analyzed from the rate constant perspective. Radical-induced pyrolysis made remarkable differences in product selectivity for benzyl phenyl ether. Similarly, the cleavage of the C al –C al bond can also be promoted using two methods of radical induction, which is referred to as a radical chain process. In contrast to benzyl phenyl ethers, the induced pyrolysis of the C al –C al bond in bibenzyl is more likely to occur via β-bond scission after the H of CH 2 is abstracted by a radical. The findings of this research would provide a theoretical foundation for comprehending the radical mechanism of direct coal liquefaction.
研究领域:
化学工程
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能源科学
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产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2021
·
IF 7.267
Pan Zhang,Yuanyuan Cui,Yongji Yao,Wei Wei,Yuanyuan Sun,Kaiqiang Zhang,Yanfeng Gao
Developing cheap and efficient materials for enhancing the photochromic performance upon visible or solar light irradiation is a hot-topic in the field of solar energy conversion . However, few inorganic photochromic materials can provide satisfying applications due to their low coloring and bleaching efficiency as well as slight color change. Here, we synthesized the bismuth tungstate (Bi 2 WO 6 ) ultrathin nanosheets with the thickness of 1.29 nm via co-precipitation-hydrothermal method using cetyltrimethylammonium bromide (CTAB) surfactant . The prepared ultrathin nanosheets show the similar crystalline structure but a narrowed band gap of 2.73 eV, as compared with the 2.86 eV of pristine Bi 2 WO 6 . Additionally, the numerous [WO 6–x Br 2x ] species and abundant “Bi–O″ vacancy pairs on the surface can serve as active sites that suppress the recombination of photogenerated electron-hole pairs and capture the photogenerated electrons to form the color trapping centers. As a result, Bi 2 WO 6 ultrathin nanosheets exhibit excellent photochromic behavior upon solar light irradiation (coloring time of 5 s) and under dark atmospheric treatment (bleaching time of 35 min) compared with WO 3 -based photochromic materials (coloring time of 20–60 min and bleaching time of 3 h days).
研究领域:
材料科学
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太阳能转换
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纳米技术
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
·
IF 4.097
Jing-Hui Zhu,Meng-Meng Li,Shao-Pu Liu,Zhong-Fang Liu,Yuan-Fang Li,Xiao-Li Hu
Carbon dots (CDs) with a fluorescence quantum yield of approximately 2.41% were prepared by simple one-step hydro-thermal synthesis of triethylenetetramine-N, N, N′, N″, N‴, N‴-hexaacetic acid (TTHA). The obtained CDs possess excitation wavelength-dependent and pH insensitive photoluminescence (PL) properties. Notably, the as-prepared CDs also exhibited unique auramine O (AO)-stimulus-responsive dual-emission fluorescence individuality, with which detection of AO using CDs has been performed through a fluorescence resonance energy transfer process. The fluorescence signals are linearly correlated with the concentration of AO over a range of 0.18–16.0 μM ( R 2 = 0.9989), with a limit of detection (3 σ ) of 54 nM. Additionally, a keypad lock and a NOR–AND logic gate was designed as well.
研究领域:
分析化学
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纳米材料科学
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环境科学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 8
·4893-4902
·
IF 10.7
Zhao Sun,Yunhan Gong,Dongfang Cheng,Zhiqiang Sun
Catalytic methane decomposition shows the prominent superiority of generating hydrogen in one step with almost no carbon oxide production; however, it suffers from catalyst deactivation and low by-product carbon quality. Herein, a series of H2-reduced NixCr2Ox+3 (abbreviated as reduced NixCr2) catalysts were designed and synthesised for highly efficient methane decomposition and carbon nanotube production. A maximum methane conversion of 87.1% and hydrogen concentration of 91.8 vol% were achieved at 750 °C without deactivation. The results from XPS, XAS, and Raman reveal that the reduced NixCr2 catalysts have significant activity and stability. On the one hand, they form the Cr–O–Ni structure, thus possessing strong Ni–Cr2O3 interaction. On the other hand, the lattice oxygen of the reduced NixCr2 catalysts induces methane activation, thus accelerating methane activation, as demonstrated by the generation of a little amount of CO. In addition, the relationship between the types of carbon deposited and Ni/Cr ratio, decomposition temperature, and time was also revealed to guide carbon nanotube synthesis. Density functional theory calculation confirms the lowest dehydrogenation barrier of Ni(111)/Cr2O3(012), demonstrating the superiority of the Cr–O–Ni catalyzed methane decomposition. These findings provide innovative ideas for the construction of functionalized materials, which will substantially promote the development of methane decomposition.
研究领域:
材料科学
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化学工程
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催化技术
✓ 已验证
DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 55
·43972-43977
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IF 3.84
Jun Hu,Dekui Shen,Shiliang Wu,Huiyan Zhang,Rui Xiao
The microwave-assisted cleavage of C–O linkages in benzyl phenyl ether was investigated at 200 °C in the presence of ZrP or SBA-15 doped with or without metal catalyst (Pd/C or Ru/C). The total yield of phenol and benzyl alcohol from benzyl phenyl ether depolymerization with ZrP was 26.91%, while the yield of phenol reached 26.11% for that with Pd/C. Hybrid catalysts performed effectively for promoting the formation of phenol. A conversion of 85.70% was achieved with ZrP–Pd/C catalyst, and the selectivity to phenol reached 47.32%. The highest yield of phenol was obtained at 1 h, and repolymerization was remarkable at longer reaction time. Based on the reaction using phenol and benzyl alcohol as the reactants, benzyl phenyl ether might be decomposed into phenol and benzyl alcohol following with the repolymerization producing thermally stable polymers in the presence of Pd.
研究领域:
化学工程
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 32
·期 30
·2202245
·
IF 19.924
Tingting Liang,Xiaqing Zhang,Lijun Su,Ruilin Hou,Bingjun Yang,Junwei Lang,Shengrong Yang,Xingbin Yan
Perovskite materials can store charge through rapid oxygen anions intercalation. Although numerous perovskite materials owing to rich selections of A and B-site elements are reported as electrodes of supercapatteries, the effect of the crystal structure of perovskite materials on their electrochemical performance has never been studied so far. Herein, using SrCo 0.9 Mo 0.1 O 3− δ , SrFeO 3− δ , Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3− δ , and LaMnO 3− δ as research targets, it is proved that their corresponding cubic structure materials display the best electrochemical performance. And then, the origin of such superiority of cubic structure for SrCo 0.9 Mo 0.1 O 3− δ is explored through experimental investigations and theoretical calculations. The results show that the increase in the content of oxygen vacancies and the enhancement of B-O hybridization of cubic structure can optimize the electronic structure of the perovskite materials, thereby improving its conductivity and accelerating the reaction kinetics. The filtering strategy based on crystal structure proposed by this report will provide a new perspective to faster and more efficient choice of perovskite materials for supercapatteries.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Zhenlong Song,Yuzhen Hu,Song Li,Jianguo Liu,Xinghua Zhang,Longlong Ma,Lungang Chen,Qi Zhang
Valorizing lignin into valuable chemicals requires the selective breaking of a large number of C–O bonds found in the β–O–4 structure. In this study, we present a one-pot strategy that utilizes two NiO/TiO2 catalysts for the photocatalytic depolymerization of β–O–4 alcohols. The S-1.6%NiO/TiO2 catalyst is used for the dehydrogenation of β–O–4 alcohols at 450 nm. Then, the L-0.8%NiO/TiO2 catalyst is employed for the hydrogenolysis of β–O–4 ketones at 365 nm. Remarkably, the dehydrogenation–hydrogenolysis tandem reaction can be conducted in one pot, which affords high yields of ketones and phenols (up to 89%) from β–O–4 alcohols. Additionally, the L-0.8%NiO/TiO2 catalyst prepared in this article is the smallest NiO/TiO2 photocatalyst reported to date, and the size of NiO in the S-1.6%NiO/TiO2 catalyst is even small enough to enter the lattice of TiO2. We successfully regulated the reaction selectivity by controlling the loading method and the amount of NiO. Our work offers a promising solution for efficiently cleaving target bonds in lignin and provides insights into the design of efficient photocatalysts.
研究领域:
化学工程
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材料科学
·
可再生资源转化
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
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2024
·
IF 4.3
Shuai Yang,Tao Li,Jun Fang,Shichong Yao,Zhenyu Li,Yunyun Liu,Jie Chen,Yuanliang Yuan,Xiaocong Zhong
N,O-codoped microporous carbon (HPC) was derived from hypnum plumaeforme via precarbonization and KOH activation and utilized as an electrode for supercapacitors. The HPC750 sample, produced at an activation temperature of 750 °C, demonstrated superior capacitive behavior due to its large specific surface area, microporous architecture, and high number of oxygen and nitrogen heteroatoms. These HPC750 electrodes have a specific capacitance of up to 424 F g −1 at a current density of 1 A g −1 while also providing excellent rate performance, maintaining >85 % capacitance over a range of 1 to 100 A g −1 . In a symmetric supercapacitor configuration using 6 M KOH and 1 M Na 2 SO 4 as electrolytes, the HPC750 electrodes exhibit high specific capacitances of 96.2 F g −1 and 65.8 F g −1 at a current density of 1 A g −1 , respectively. With the Na 2 SO 4 electrolyte, the device achieved a peak energy density of 29.9 W h kg −1 and a peak power density of 225 W kg −1 . In addition, the electrodes retained approximately 90 % of their initial capacitance after 15,000 cycles at a current density of 5 A g −1 .
研究领域:
材料科学
·
能源存储
·
植物学
✓ 已验证
DOI
高影响因子
ACS Nano
·
2025
·
IF 16
Shengxi Li,Yanxin Shang,Xuening Ren,Anqi Zhao,Nan Chen,Li Li,Feng Wu,Renjie Chen
Aqueous lithium-ion batteries (ALIBs) have attracted increasing attention for their inherent safety and environmental benefits. However, the narrow electrochemical stability window of water (1.23 V) imposed by hydrogen evolution reaction (HER) and high melting point (0 °C) critically limits the energy density and low-temperature operation. In this work, we report an electrolyte design principle that water activity can be suppressed by strengthening the O–H bonds between water molecules and regulating the pH. A strong polar solvent N,N-dimethylformamide (DMF) interacts with H2O through intermolecular hydrogen bonds, thereby reinforcing the covalent O–H bonds of water. Meanwhile, KOH renders the electrolyte alkaline, inhibiting water dissociation kinetics and consequently raising the HER overpotential. The designed LD1.7W0.6–KOH electrolyte exhibits a freezing point below −82 °C and expanded electrochemical stability window of 4.3 V. The 2.5 V aqueous LiMn2O4/Li4Ti5O12 full cell delivers 2000 cycles at a rate of 6 C with a Coulombic efficiency of 99% at 30 °C and over 1950 cycles at 0 °C. This work offers atomic-level insights into alkaline HER while providing guidance for advancing low-temperature aqueous batteries by tuning the electrolyte structures.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Zhao Sun,Shufan Yu,Sam Toan,Rufat Abiev,Maohong Fan,Zhiqiang Sun
Steam reforming of methanol is a promising approach to achieving hydrogen storage, transportation, and in situ supply. However, this technology is restricted by its high CO selectivity and catalyst deactivation. In this study, CuCr2O4-based catalytic oxygen carriers are tailored for lattice oxygen participating in low-temperature methanol reforming. We found that the low-temperature activation of methanol originated from Cu–O–Cr structure intensification and highly activated lattice oxygen induction. Specifically, methanol can be activated at temperatures as low as 160 °C, on the one hand, attributed to the reinforcement of the Cu–O–Cr structure and, on the other hand, owing to the highly reactive lattice oxygen from the CuO4 tetrahedron in the CuCr2O4 spinel. Combined with XAS and Raman results, the formation of the Cu–O–Cr structure is demonstrated. The hydrogen production rate with an applied CuCr2O4-based catalytic oxygen carrier is 53.2% higher than the control group without Cu–O–Cr formulation. Satisfactory cyclic stability is retained after the 50th lattice oxygen induction and supplement cycle, ascribing to the Cu–O–Cr structure that strongly intensifies Cu–Cr2O3 interactions. DFT results reveal that the process of CH3OH → CH3O* is the rate-determining step. Compared to Cu(111) and Cr2O3(110), the tailored Cu(111)/Cr2O3(110) surface with a Cu–O–Cr structure exhibits the lowest potential barrier during this process, promoting low-temperature methanol reforming.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）