Molecular Catalysis
·
2023
·
IF 4.6
Shiwei Feng,Chengping Zhang,Hengdao Quan
As an environmentally friendly cleaning agent, Z -1-chloro-3,3,3-trifluoropropene (HCFO-1233zd( Z )) can realize industrial production by the isomerization of HCFO-1233zd( E ). Herein, various isomerization catalysts with different structures, compositions and acid properties were prepared through the fluorination of γ-Al 2 O 3 with CHF 3 by controlling the activation conditions. For the first time, the catalysts for HCFO-1233zd( E ) isomerization were systematically studied by XRD, N 2 physisorption, XPS, SEM, MAS NMR spectroscopy, NH 3 -TPD and py-IR. The active site of this reaction was revealed and the catalyst deactivation mechanism was proposed. It turned out that HCFO-1233zd( E ) isomerization prefers to occur at Lewis acid sites with moderate density and strength. The amorphous particles composed of γ-Al 2 O 3 , Al 2 O 3 (F) and α-AlF 3 ( R 3 ¯ c ) at 450 °C exhibit highly catalytic activity for HCFO-1233zd( E ) isomerization. After 100 h evaluation, it was found that residual γ-Al 2 O 3 can be fluorinated by HCFO-1233zd( E ) to form needle-like structures which could induce the amorphous Al 2 O 3 (F) particles to reorganize and give cubic structures, where the Lewis acid properties were enhanced, leading to catalyst deactivation.
研究领域:
催化
·
化学工程
·
材料科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Yanan Yang,Yu Zhang,Hong Zheng,Baichao Zhang,Qi Zuo,Kaiyue Fan
A key challenge in trace heavy metals removal from drinking water by adsorption technology is to achieve high adsorption capacity and rapid uptake speed of adsorbent. Herein, we report a functionalized double modified covalent organic framework (DMTD–COF–SH) bearing high-density sulfur and nitrogen chelating groups provided simultaneously by 2,5-dimercapto-1,3,4-thiadiazole (DMTD) and 1,2-ethanedithiol, which was prepared via a facile one-pot thiol-ene “click” reaction. PXRD , FTIR, XPS, SEM, BET and 13 C MAS NMR confirmed their successful graft, and DMTD was found to be more easily grafted on the COF surface layer than 1,2-ethanedithiol. The as-prepared DMTD–COF–SH showed remarkable adsorption capacity and ultrafast uptake dynamics to trace heavy metals owing to the synergistic effects resulting from densely populated sulfur and nitrogen chelating groups within ordered COF mesopores and at the COF surface. On the basis of the drinking water treatment units standard NSF/ANSI 53–2020, when the adsorbent dosage was 10 mg/30 mL and 20 mg L −1 calcium ions coexisted, the lead concentration decreased from initial 150 μg L −1 to 2.89 μg L −1 within 10 s, far below the allowable limit of world health organization (WHO) drinking water standard (10 μg L −1 ), and the maximum adsorption capacity meeting the standard attained 14.22 mg g −1 . The adsorbent also exhibited excellent stability, wide applicable pH range and outstanding adsorption performance for coexisting trace lead, mercury, cadmium, chromium (VI) and copper in tap water, indicating that the DMTD–COF–SH material has excellent application prospect for trace heavy metals removal from drinking water.
研究领域:
环境科学
·
材料科学
·
水处理
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Nano
·
2020
·
IF 14.588
Xiang Xu,Yang Guo,Brian P. Bloom,Jianjun Wei,Haoyang Li,Hailong Li,Yankun Du,Zheng Zeng,Liqing Li,David H. Waldeck
High entropy alloy nanoparticles (HEA-NPs) are expanding their influence in many fields. To explore the electronic structures in such multielemental systems, HEA-NPs were synthesized on two different carbon substrates through carbothermal shock and in situ reduction methods. The relationship between the apparent core level energy shifts (negative or positive) and the electron density changes among the components of quinary-metal HEA-NPs was investigated by X-ray photoelectron spectroscopy (XPS) analysis and first-principles electronic structure calculations. It was found that Cu displays a negative core level shift while Fe, Co, Mg, Cr, and Mn display a positive core level shift. While experiments show an apparent positive core level shift for Ni, electronic structure calculations reveal that this arises from shifts in the Fermi level and that the electron density redistribution in Ni behaves more like Cu than the other elements. The findings show that the electron density redistribution in the NPs occurs from less electronegative elements to more electronegative ones. This work should guide the design of HEA-NPs to expand their potential applications in mechanical structures, medicine, catalysis, and energy storage/conversion.
研究领域:
材料科学
·
纳米技术
·
表面科学
·
计算化学
·
催化
·
能源存储/转换
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Chaogang Ban,Yang Wang,Jiangping Ma,Yajie Feng,Junjie Ding,Youyu Duan,Xue Liu,Bin Zhang,Jinjing Tang,Xiaoping Tao,Liyong Gan,Shuangshuang Tan,Xiaoyuan Zhou
Rational fabricating advanced photocatalysts to recycle CO 2 into solar fuel is one of the most promising approaches to simultaneously address energy shortages and global warming. TiO 2 has been widely used in photocatalytic CO 2 reduction due to its abundant reserves, non-toxicity and harmlessness etc. However, it remains significantly challenging for practical applications due to the fast electron-hole recombination. Herein, we design a direct TiO 2 based Z-Scheme heterojunction by self-assembly of C-doped TiO 2 nanoparticles on 3D hierarchical petal of flower-like β-Bi 2 O 3 (C-TiO 2 /β-Bi 2 O 3 ). In situ electron paramagnetic resonance tests, in situ X-ray photoelectron spectroscopy and theoretical calculations reveal that electrons are transferred from β-Bi 2 O 3 to C-TiO 2 due to the formation of Z-Scheme heterojunction, which greatly accelerates the separation of photogenerated carriers to promote efficient CO 2 photoreduction. Ultimately, the optimal heterojunction shows significantly enhanced photocatalytic activity for CO 2 reduction to CO (31.07 μmol g –1 h −1 ) compared to the pure TiO 2 (3.28 μmol g –1 h −1 ) without using any photosensitizers and sacrificial agents. This work provides a unique insight to design direct Z-Scheme heterojunctions and delivers a promising photocatalyst for overcoming global warming and energy-supply issues.
研究领域:
材料科学
·
环境科学
·
化学工程
·
光催化
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 4
·1537-1549
·
IF 3.5
Chen Yongjin,Li Yaru,Fu Jianbo,Zhang Mi,Ren Hui,Jiao Qingjie
Aluminum hydride (AlH 3 ), as a potential new metal fuel, has attracted extensive attention in the field of hydrogen storage materials, propellants and energetic materials due to its excellent properties. In this paper, a new organic liquid phase reduction method was used to prepare AlH 3 , and the microstructure and composition of the prepared samples were characterized by SEM–EDS, XRD, FT-IR, XPS, etc. The main crystal phase of the prepared AlH 3 was α-AlH 3 , with high quality and no other impurities. The thermal decomposition behavior and non-isothermal reaction kinetics of AlH 3 were investigated by TG-DSC. The results show that there are three exothermic stages in the heating process of AlH 3 : dehydrogenation of AlH 3 , first oxidation of Al, and second oxidation of Al. The activation energy of the dehydrogenation of AlH 3 is 77.8675 kJ/mol (Kissinger method) and 81.4862 kJ/mol (Ozawa method), respectively. The morphology evolution of AlH 3 particles during the heating process (300–3000 K) was simulated using a reaction kinetics method based on the ReaxFF force field. The response behavior of AlH 3 in the instantaneous high-temperature detonation environment was investigated using the high-energy laser-induced shock wave technique. Under the impact of a high-energy laser (1006 mJ), the AlH 3 sample undergoes an ultra-fast reaction and generates a large amount of plasma. The expansion of the plasma pushes the surrounding air to form a supersonic shock wave and propagates forward. The shock wave propagation velocity of AlH 3 is 690.99 m/s in the range of 2.1–12.35 μs, and the higher the laser energy, the faster the shock wave propagation velocity. This study provides the basis for the application of AlH 3 . Graphical Abstract
研究领域:
氢存储材料
·
推进剂
·
高能材料
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材料科学
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化学工程
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Chuanyi Ma,Jian Li,Yi Wang,Zhanguo Li
Hydrogels have attracted widespread attention in the field of surface radioactivity decontamination due to their mild and rapid decontamination processes, as well as their tunable properties. However, fabricating decontamination hydrogels with suitable mechanical properties and environmental adaptability remains challenging. In this study, a tough and freeze-resistant hydrogel (PEAG) was prepared based on graphene oxide (GO), polyvinyl alcohol (PVA), agar (AG), and ethylene glycol (EG) for efficient removal of surface radioactive uranium (VI). Due to the dynamic action of borax and the formation of a nanocomposite dual-network structure, PEAG possesses improved modulus and excellent self-healing properties, allowing the hydrogel to be easily applied to surfaces and to perform operations such as stretching and peeling. In addition, it is found that the PEAG achieves excellent decontamination rates for radioactive uranium (VI) on glass (88.53±1.43 %), stainless steel (86.72±3.41 %), rubber (67.0±2.43 %), ceramics (82.39±1.78 %), and cement (64.52±1.72 %) surfaces, respectively. XPS and contact angle experiments demonstrated that the improved decontamination performance of PEAG is mainly due to the abundant hydroxyl and carbonyl functional groups in the graphene oxide adsorbent, which provide a rich source of complexation sites and enhance its hydrophilic properties for PEAG. Additionally, due to the incorporation of EG, the PEAG hydrogel exhibits good environmental adaptability, which can retain internal moisture and maintain softness and decontamination stability at low temperatures of −20°C. Therefore, PEAG hydrogel is a promising and sustainable candidate material for various surface radioactive decontamination scenarios.
研究领域:
材料科学
·
环境科学
·
核工程
·
化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2025
·
IF 4.8
Yanrui Su,Xiaoyu Li,Zimu Gao,Jiajia He,Zizhen Liu,Linjun Duan,Tian Sun,Jiaoge Wu,Dan Liang,Chaojun Wei,Faying Fan,Wa Gao
The incorporation of dual redox sites within catalytic materials for H 2 O 2 activation represents a promising approach to enhance the efficiency of pollutant decomposition. In this study, Cu 2 O modified CuFe-LDH nanocomposite (Cu 2 O/CuFe-LDH) was successfully synthesized via in situ topotactic transformation of CuFe-LDH. The catalytic degradation performance of the Cu 2 O/CuFe-LDH nanocomposite was investigated utilizing tetracycline hydrochloride (TCH) as a typical antibiotic contaminant. It demonstrated exceptional catalytic activity, achieving a TCH elimination rate of 93.0 % in 60 min. A rate constant value of 0.0426 min −1 was calculated for the pseudo-first-order kinetic model, which was 1.6 times and 5.0 times higher than those of CuFe-LDH and Cu 2 O, respectively. Moreover, the Cu 2 O/CuFe-LDH nanocomposite demonstrated remarkable cycling stability (85 % degradation rate after 5 recycling cycles), a wide pH range (3−11), resistance to background ion interference, and lower toxicity of the products of degradation. Based on radical scavenger tests and electron paramagnetic resonance (EPR) spectroscopy, it was verified that TCH degradation was mediated by 1 O 2 , •OH and •O 2 - , with 1 O 2 playing an essential role. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) investigations indicate that the remarkable catalytic efficacy of Cu 2 O/CuFe-LDH is predominantly due to the synergistic interactions between Cu 2 O and CuFe-LDH, with Cu 2 O promoting the accelerated dual Cu 2+ /Cu + and Fe 3+ /Fe 2+ cycling. Thus, the Cu 2 O/CuFe-LDH nanocomposite exhibits exceptional efficiency, environmental friendliness and recyclability, rendering it an ideal candidate for practical wastewater treatment applications.
研究领域:
环境科学
·
材料科学
·
化学工程
·
纳米技术
·
催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2025
·
IF 1.6
Wang Weiran,He Hui,Wang Zhifen
In this study, two new, highly selective, acid-resistant and reusable functionalized magnetic chitosan-based composites (FOS@C-DTPA and FOS@C-PBTCA) were successfully prepared. The adsorption performance of the composites was systematically evaluated through controlled variations in solution pH, exposure time, and starting uranium content, while the underlying mechanisms for uranium uptake were analyzed using kinetic models and thermodynamic equilibrium studies. In the multi-ion competition experiments, a high degree of selectivity for U(VI) was demonstrated; good cyclic regeneration performance was shown in both cycling experiments. XPS analysis combined with complementary characterization techniques demonstrated that uranium adsorption was predominantly caused by surfaces complexation between U(VI) ions and the composite material’s abundant functional groups rich in carbon, nitrogen, and oxygen on the composite material. At pH 5, FOS@C-PBTCA demonstrated an adsorption capacity of 303.53 mg·g −1 , while FOS@C-DTPA achieved 487.39 mg·g −1 at pH 6. The proposed approach aims to achieve efficient and selective uranium extraction by leveraging an anion-assisted synergistic mechanism, enabled through the rational design of acid-resistant and recyclable magnetic composite adsorbents.
研究领域:
环境科学
·
材料科学
·
化学工程
·
核化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2025
·
IF 3.5
Xiaohui Li,Pengjun Zhao,Wenwen Kong,Aimin Chang,Bo Gao
Understanding electrical transport mechanisms and key thermal stability factors in high-temperature thermosensitive ceramics is essential for developing highly stable temperature sensors under extreme thermal conditions. This study develops the high-entropy pyrochlore stannates (La 0.2 Nd 0.2 Sm 0.2 Gd 0.2 M 0.2 ) 2 Sn 2 O 7 (M = Eu, Dy, Ho, or Yb) via solid-state synthesis, demonstrating exceptional negative temperature coefficient (NTC) behavior across 300 – 1400 °C. Hall measurements and X-ray photoelectron spectroscopy (XPS) analyses reveal a dual redox mechanism for these ceramics: partial reduction of Sn 4+ to Sn 2+ at B-sites and rare-earth ions (Sm/Eu/Yb) to RE 2+ at A-sites, generating hole-dominated p-type conductivity. The materials exhibit outstanding thermal stability, with resistance drift below 1.96% after 500 hours at 1400 °C, attributed to the entropy-stabilized structure that effectively suppresses lattice disorder transformation. Aging studies further demonstrate that high oxygen vacancy concentrations lead to resistance drifts, as oxygen filling at elevated temperatures oxidizes RE 2+ to RE 3+ , reducing charge carriers and ultimately increasing resistivity. This study elucidates for the first time the hole-dominated conduction mechanism arising from dual-site cation valence changes (Sn/RE) and the regulation effect of oxygen vacancies on high-temperature stability, which provides an important theoretical basis and material design strategy for the development of the next-generation high-temperature NTC sensors with excellent stability.
研究领域:
材料科学
·
陶瓷材料
·
电气工程
·
固态物理
·
热传感器
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Zia Ahmad,Yun Li,Sajjad Ali,Jiajia Yang,Faheem Jan,Yun Fan,Xiaoyi Gou,Qingye Sun,Jiping Chen
Design of amidoxime-based adsorbents in a cooperative and synergistic manner together with a concept of facile and green fabrication is becoming highly desirable to harvest uranium from seawater. Herein, taking benefit of supramolecular ionic-crosslinking and hydrogen bonding interactions, we have reported a simple and environmentally benign approach to construct novel bifunctional poly(amidoxime)-alginate-poly(acrylic acid) (PAO-A-PAA) composite beads. As a result of synergistic uranyl binding, the PAO-A-PAA composite beads reached a high adsorption capacity of 735.1 mg g −1 for uranium aqueous solution (36 ppm), which is 2.24 and 1.46 times that of monofunctional Alg-PAA (328.1 mg g −1 ) and Alg-PAO (502.2 mg g −1 ), respectively. More importantly, the PAO-A-PAA exhibits excellent selectivity towards U(VI) in the presence of natural organic matter and multiple coexisting metal ions in simulated seawater. The XPS analysis reveals the utilization and coordination of both amidoxime and carboxylate ligands of PAO-A-PAA for uranyl binding, which results in energetically more stable synergistic uranyl complexes (E binding = −9.45 to −10.34 eV) as proved by the density functional theory study. The adsorption efficiency of PAO-A-PAA is further supported by its ability to extract µg L −1 -level uranium in real seawater (94.7–99.5%). The PAO-A-PAA also demonstrates good mechanical and chemical stability over a wide pH range, as well as good reusability. These findings provide insight into the significance of designing efficient sorbent material for enhanced uranyl capture via a supramolecular strategy.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2023
·
IF 5.2
Xuan Liu,Jie Gong,Kai Jiang,Xiaojuan Lai,Yu Tian,Kang Zhang
In order to reduce the apparent viscosity of lignite coal water slurries (CWSs) and improve its static stability, a series of three-arm amphiphilic block copolymers have been prepared through RAFT polymerization by using poly(ethylene glycol) methyl ether acrylate (PEGMA) and sodium 4-vinylbenzenesulfonate (SSNa) as hydrophilic monomers and styrene (St) as hydrophobic monomer. The chemical structure of the copolymers has been investigated, and the impact of relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content on the pulping performance of three-arm amphiphilic block copolymers has been examined. The lignite coal water slurries (CWSs) prepared from the block copolymer tri -P(St 50 - s -SSNa 50 ) 10K - b -PPEGMA 10K exhibit a remarkably low apparent viscosity of 395 mPa·s and excellent static stability when the coal content is at 55 wt% and dispersant content is at 0.5 wt%. Moreover, these CWSs can achieve a maximum pulping concentration of up to 59 wt%. Additionally, the thermogravimetric test reveals insights into the water occurrence in CWSs, indicating that higher levels of free water content correspond to lower apparent viscosities. Suitable hydrophobicity facilitates the removal of internal water from lignite by dispersants, disrupting its flocculation structure and promoting CWSs formation. Meanwhile, the presence of ionic groups enhances the static stability of the resulting CWSs. Furthermore, the adsorption behavior of the three-arm amphiphilic block copolymer dispersant in lignite has been analyzed through XPS testing to elucidate its dispersion mechanism. The use of three-arm amphiphilic block copolymers in preparing lignite CWSs results in lower apparent viscosity and improved static stability, attributed to the amphiphilic and steric hindrance effects of dispersants. This not only expands the application range of lignite CWSs but also highlights the significant potential of this type of dispersant.
研究领域:
聚合物化学
·
材料科学
·
能源工程
·
化工工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 15
·12467-12475
·
IF 2.22
Xie Xinxin,Wang Hui,Zhou Yanping,Huang Kama
Microwave-assisted reduction of graphene oxide (GO) has been reported to be very effective in producing high-quality reduced graphene oxide (rGO) and its composites. However, either pretreatment (e.g., heating) or an external trigger (e.g., copper wire) is required to initiate the process due to the poor microwave absorption ability of GO. In this work, we report a one-step self-triggered microwave-arcing approach for synthesizing rGO composites (NiCo/rGO) for the first time. Evidenced by permittivity value, the synergic microwave absorption between GO and the metal nitrate salts is found to play an important role in initiating the process. From XRD, Raman, XPS and TEM results, it is proposed that mildly reduced rGO is firstly formed after 10 s, which further enables stronger microwave absorption to facilitate the complete reduction of GO as well as formation of well-crystallized NiCo nanoparticles about 10 nm after 90 s. The as-synthesized product shows a minimum refection loss value of − 44.48 dB with an absorption bandwidth of 3.66 GHz at 4.5 mm.
研究领域:
材料科学
·
纳米技术
·
电磁材料
·
复合材料
✓ 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）