ACS Omega
·
2018
·
IF 0
Yucui Hou,Zengqi Lin,Muge Niu,Shuhang Ren,Weize Wu
The conversion of abundant renewable cellulose into versatile formic acid (FA) is a potential process for efficient energy storage and application. Vanadium(V)-catalyzed oxidation with O2 in acidic aqueous media now is the most common method to realize the FA production from cellulose with both high yields and high purity. However, vanadium-based catalysts are difficult to synthesize and expensive. Thus, the seeking for cheaper catalysts with the same high efficiency is expected. In this work, after testing a variety of metal salts in acidic aqueous solution for the conversion of cellulose under O2, iron(III) was found as a cheaper and readily available catalyst for FA formation, with a comparable yield (51.2%, based on carbon) with that of vanadium(V). The effect of reaction parameters was studied. The competition between oxidation and hydrolysis was found and discussed in detail. FeCl3 and H2SO4 can accelerate oxidation and hydrolysis, respectively, whereas suppress the other. The effects can reflect on the product distribution. Intermediates were found and the pathway from cellulose to products was reasonably proposed. The reusability of the catalytic system shows good performance after four runs. The mechanism study suggests a catalytic ability by a mutual transformation between iron(III) and iron(II), where iron(III) oxidizes substrates to iron(II) that is reoxidized by O2.
研究领域:
化学
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能源科学
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催化科学
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DOI
PubMed
MATERIALS LETTERS
·
2021
·
IF 3.423
Lijian Song,Xiahua Zuo,Ying An,Jin Zhan,Youchen Zhang,Weimin Yang,Jing Tan,Lisheng Cheng
Dopamine (DA) has been applied in surface chemistry because of its green and simple polymerization process. However, the polymerization kinetics is slow for mass production. Herein, we proposed a novel method to increase the polymerization rate of DA significantly. The DA solution was treated by a two-step method using microwave irradiation and oxygen oxidation . As a result, the DA solution turned dark only in 6 min. The UV–vis spectra and molecular dynamics showed that microwave irradiation promotes the generation of reactive oxygen species, and the oxygen is used as a supplement to compensate for the overflow of oxygen during the microwave heating process. This study provides a new promising choice to polymerize DA quickly and will inspire related applications in various fields.
研究领域:
材料科学
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化学工程
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生物医学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yaozhi Zhang,Bingru Wang,Fang Wang,Yasen Dai,Shuhang Ren,Yucui Hou,Weize Wu
This work designs a new method for recovering spent LiFePO 4 cathode materials, aiming to address issues with traditional hydrometallurgy processes such as complex operations, low lithium recovery rates, and high wastewater discharge. The method involves using a deep eutectic solvent (DES) composed of chloroacetic acid and ethanol, and oxygen as an oxidant, for the cooperative leaching of LiFePO 4 powders. Based on the acidic nature of the DES and the oxidizing properties of oxygen, LiFePO 4 was undergone an in-situ transformation into solid FePO 4 , while 100% of lithium was dissolved in the DES with high selectivity. The FePO 4 product can be recovered by filtration, and the addition of oxalic acid to the filtrate allows for lithium recovery. Importantly, the structure of the DES remained unchanged after use, allowing for three recycling cycles without a significant decrease in LiFePO 4 recovery efficiency. This process is environmentally friendly, with no generation of acidic or alkaline wastewater, and boasts high metal recovery rates, showcasing its huge potential for application.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 18
·9989-9999
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IF 11.9
Guang-Xing Dong,Meng-Ran Zhang,Ke Su,Zhao-Lei Liu,Min Zhang,Tong-Bu Lu
Activation and catalytic transformation of C–H bonds under mild conditions has long been a great challenge for the chemical industry. Herein, we report a halide-perovskite-based photocatalyst composed of manganese-doped CsPbBr3 decorated on BiVO4 for the efficient and selective transformation of nonpolar CH4 to oxygenates using air as an oxidant. At room temperature and atmospheric pressure, the yield and selectivity of oxygen-containing hydrocarbons (CH3OH and HCHO) from photocatalytic CH4 oxidation are as high as 533.5 μmol g−1 h−1 and 94.8%, respectively. Moreover, transient intermediate capture and isotope labeling experiments demonstrate that the oxygen sources of products for this heterojunction are mainly from O2, which contrasts with that from water in pristine BiVO4, owing to the difference in the pathway of O2 reduction induced by the increased thermodynamic driving force. This work provides an effective strategy for the design and development of a cost-effective catalyst system for CH4 conversion in a mild manner.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Yu-Zhen Xu,Yu-Le Wang,Yu-Dong Shan,Song-Hai Wu,Yong Liu,Xu Han
Selective oxidation of cyclohexene (Cy) to cyclohexene oxide (Cy-ep) by O2 under solvent- and initiator-free conditions is a challenge in chemical processes, which is still constrained by its low selectivity (theoretical selectivity of 50.0%). Given the low epoxide selectivity (<20.0%) of single metal catalysts, we propose a relay catalysis strategy on the oxidation of Cy to Cy-ep with high selectivity by the spherical Mg–Mo bimetallic oxide (MMO). Such a relay catalyst exhibits a desirable Cy conversion of 31.0% and a high selectivity of 49.3% toward Cy-ep. Meanwhile, the high stability and reusability of MMO also indicate its potential to be used for industrial scale-ups. A series of characterizations and DFT calculations reveal that the negatively charged lattice oxygen in [MgII–O–II] adsorbs allylic H of Cy to weaken the bond energy of the allylic C–H bond and form Cy•, and then Cy• rapidly traps O2 to give CyOO•, which subsequently abstracts H from allylic C–H of another Cy to form 2-cyclohexene-1-hydroperoxide (Cy-OOH) and Cy•, achieving the propagation cycle. On the other hand, the Mo(VI) site in MMO catalyzes the produced Cy-OOH peroxo, which then oxidizes Cy to Cy-ep and 2-cyclohexene-1-ol. This work provides insight into the relay catalyst for the epoxidation of olefin with O2 with high selectivity under solvent- and initiator-free conditions.
研究领域:
化学工程
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材料科学
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催化化学
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产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2016
·
IF 3.389
Mazloom Shah,Qing-Xiang Guo,Yao Fu
The Pd, Ni, Ni-Sn, Cu and Ag@Pd nanocatalyst having different shape and size were used for direct dehydrogenation of cyclic ketones to the corresponding phenols in the presence of O 2 as the oxidant. Among all catalyst tested, metallic Pd-1 nanoparticles exhibited excellent catalytic performance both in presence and absence of p-toluenesulfonic acid. The dehydrogenation of cyclohexanone catalyzed by Pd-1 nanocatalyst led to a 93% yield of the desired cyclohexenone and phenol. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed that there was no change in morphology, crystal phases and particles size of Pd-1 nanocatalyst after the reaction.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
J. Ping,S. Rauf,S.Y. Huang,W.S. Li,S.H. Liang,R.L. Wang,Q.A. Huang,V.V. Morchenkov,C.P. Yang
The electrochemical behavior of activated carbon (AC) has been studied in the presence of air at negative potentials in 0.5M Li 2 SO 4 aqueous electrolyte applying the linear sweep voltammetry (LSV). The AC electrodes of low mass loading are disposed and found with distorted LSV curves at constant scan rate, rather than formation of symmetric rectangular shape. Such unusual phenomenon for AC in the electrolyte exposed to air alternatively can be reflected by the discharge capacity of 145 mAh/g with a pretty high coulombic efficiency (332%) obtained in the galvanostatic charge-discharge (GCD) test. Meanwhile, the variation in current with scan rate at fixed potentials corresponds to the remarkable deviation of exponent in the power-law equation from the value 1. The oxidative effect of O 2 and H 2 O is investigated to explain the abnormal electrochemical behavior of AC. In the vessel with N2 flow, AC turns to exhibit recognizable capacitive behavior without considering residual dissolved oxygen in the electrolyte. The self-discharging of AC from 0V to around -0.2V without any external bias is observed in the electrolyte of low level of dissolved oxygen. The above results show the improved electrochemical stability of AC in the absence of air, providing information of value based on application for aqueous lithium-ion hybrid supercapacitors using AC anode.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2020
·Vol. 151
·期 3
·901-908
·
IF 2.482
Wu Yuting,Yang Long,Wu Bo,Li Jie,Liu Binyao,Ke Gaili,Dong Faqin,Zhou Yong,He Huichao
It has been reported that β -MnO 2 has photocatalytic activity for the oxidative-coupling of 2-naphthols into 1,1′-bi-2-naphthols. Nevertheless, it is hard to exclude the possibility that the oxidative-coupling of 2-naphthols is initiated by β -MnO 2 catalysis in dark due to the insufficient investigations in the related reports. In the present work, the oxidative-coupling of 2-naphthols into 1,1′-bi-2-naphthols with different phases MnO 2 catalysis in dark and under visible-light irradiation were systematically investigated. The results revealed that the oxidative-coupling of 2-naphthols is jointly initiated by MnO 2 catalysis and O 2 -oxidation, not by MnO 2 photocatalysis. Among the α -MnO 2 , β -MnO 2 , γ -MnO 2 and δ -MnO 2 catalysis, β -MnO 2 catalysis has the optimal performance, its selectivity for the oxidative-coupling of 2-naphthols into 1,1′-bi-2-naphthols is close to 100%, and its catalytic capacity could be well retained after multiple using. Our findings provide comprehensive and accurate understanding the catalytic role of MnO 2 for the oxidative-coupling of 2-naphthols into 1,1′-bi-2-naphthols. Graphic In the present work, the oxidative-coupling of 2-naphthols into 1,1′-bi-2-naphthols was proved to be jointly initiated by MnO 2 catalysis and O 2 -oxidation, not by MnO 2 photocatalysis. β -MnO 2 has the optimal catalytic activity for the oxidative-coupling of 2-naphthols relative to α -MnO 2 , γ -MnO 2 and δ -MnO 2 .
研究领域:
催化化学
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有机合成
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材料化学
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物理化学
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纳米催化
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DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 128
·105747-105752
·
IF 3.84
Yuanyuan Zheng,Xiaoming Zhang,Yi Yao,Xiaohong Chen,Qihua Yang
Ultra-small Au nanoparticles (<2 nm) supported on hollow silica nanospheres were successfully fabricated with the aid of chemical modification (–SH groups) or through simple immersion method, leading to supported catalysts Au/SH-HNS and Au/HNS. The resulting solid catalysts showed good thermal stability and the small particle sizes could be remained even at high temperature of 350 °C. Such catalysts were catalytically active in the oxidation of styrene using O2 as oxidant under 1 atm pressure. The catalytic results showed that the activity strongly depends on the Au loading amount, and the loading of 4–5 wt% led to the highest activity. Significant rate enhancement was observed with gold nanoparticles supported on pure silica in comparison with thiol modified silica nanospheres, suggesting the negative effects of thiol groups. The solid catalyst could be reused at least 8 reaction cycles without significant decrease in activity and selectivity. This study not only supplies an active, recoverable catalyst for the green transformation of styrene, but also demonstrates that the hollow silica nanosphere material has a superior ability in stabilizing metal nanoparticles against growth.
研究领域:
纳米催化
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材料化学
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绿色化学
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有机氧化反应
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多相催化
✓ 已验证
DOI
高影响因子
ACS Nano
·
2024
·
IF 15.8
Yuansheng Shi,Fushan Geng,Yang Sun,Pengfeng Jiang,Wang Hay Kan,Wei Tong,Xueyi Lu,Guoyu Qian,Nan Zhang,Bin Wei,Bingwen Hu,Dapeng Cao,Xia Lu
The irrational utilization of an anionic electron often accompanies structural degradation with an irreversible cation migration process upon cycling in sodium-layered oxide cathodes. Moreover, the insufficient understanding of the anionic redox involved cation migration makes the design strategies of high energy density electrodes even less effective. Herein, a P3-Na0.67Li0.2Fe0.2Mn0.6O2 (P3-NLFM) cathode is proposed with the in-plane disordered Li distribution after an in-depth remolding of the Li ribbon-ordered P3-Na0.6Li0.2Mn0.8O2 (P3-NLM) layered oxide. The disordered Li sublattice in the transition metal slab of P3-NLFM leads to the dispersed |O2p orbitals, the lowered charge transfer gap, and the suppressed phase transition at high voltages. Then the enhanced Mn–O interaction and electronic stability are disclosed by the crystal orbital Hamilton population (COHP) analysis at high voltage in P3-NLFM. Furthermore, ab initio molecular dynamics (AIMD) simulation suggests the order/disorder of the transition metal layer is highly correlated with the stability of the Li sublattice. The cross-layer migration and loss of Li in P3-NLM are suppressed in P3-NLFM to enable the high reversibility upon cycling. As a result, the P3-NLFM delivers a high capacity of 163 mAh g–1 without oxygen release and an enhanced capacity retention of 81.9% (vs 42.9% in P3-NLM) after 200 cycles, which constitutes a promising approach for sustainable oxygen redox in rechargeable batteries.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）