Industrial Chemistry & Materials
·
2024
·
IF 0
Jiayao Cui,Junyong Min,Hao Wang,Jianglan Shui,Lishan Peng,Zhenye Kang,Jieyuan Liu,Qingjun Chen,Shuo Bai,Yanrong Liu
Developing single-atom Fe–N4/C catalysts is crucial for the large-scale implementation of proton exchange membrane fuel cells (PEMFCs). While Fe–N4/C catalysts are inherently active in accelerating the slow ORR process, their performance is still inferior to that of Pt/C. Herein, a trace Co-doped Fe single-atom catalyst (Fe(tCo)–N–C) containing more active Fe2N8 sites has been synthesized. Interestingly, compared with typical FeN4 sites in an Fe–N–C electrocatalyst, the Fe2N8 sites generate a larger Fe–N bond length due to Co-doping. The elongated Fe–N bond in Fe2N8 lowers the d-band center and charge density of iron sites, enhancing the ORR process by facilitating the formation of *OOH and generation and desorption of *OH. Fe(tCo)–N–C manifested excellent acidic and alkaline ORR activity, with a half-wave potential (E1/2) of 0.80 V in HClO4 solution and 0.89 V in KOH medium. More importantly, high peak power densities (Pmax) were realized by applying Fe(tCo)–N–C in PEMFCs, with the Pmax reaching 890 mW cm−2 in H2–O2 and 380 mW cm−2 in H2–air. Additionally, trace Co dopants in the catalyst improved carbon graphitization and provided high ORR catalytic stability. This research introduces an innovative approach to engineering highly active Fe2N8 sites, providing valuable insights for the sustainable progress of PEMFC technology.
研究领域:
电化学
·
催化
·
能源材料
·
燃料电池
·
纳米技术
✓ 已验证
DOI
CHINESE JOURNAL OF CATALYSIS
·
2021
·
IF 8.271
Fangjun Shao,Zihao Yao,Yijing Gao,Qiang Zhou,Zhikang Bao,Guilin Zhuang,Xing Zhong,Chuan Wu,Zhongzhe Wei,Jianguo Wang
The development of bifunctional catalysts for the efficient hydrogenation and acceptorless dehydrogenation of N -heterocycles is a challenge. In this study, Ru 2 P/AC effectively promoted reversible transformations between unsaturated and saturated N -heterocycles affording yields of 98% and 99%, respectively. Moreover, a remarkable enhancement in the reusability of Ru 2 P/AC was observed compared with other Ru-based catalysts. According to density functional theory calculations, the superior performance of Ru 2 P/AC was ascribed to specific synergistic factors, namely geometric and electronic effects induced by P. P greatly reduced the large Ru-Ru ensembles and finely modified the electronic structures, leading to a low reaction barrier and high desorption ability of the catalyst, further boosting the hydrogenation and acceptorless dehydrogenation processes.
研究领域:
催化化学
·
材料科学
·
理论化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Hefang Liu,Shunyan Ning,Zengyuan Li,Shichang Zhang,Lifeng Chen,Xiangbiao Yin,Toyohisa Fujita,Yuezhou Wei
In this work, a novel silica-based N-donor ligand functional adsorbent (SiVpC) is prepared by in situ polymerization for the efficient separation of palladium from high level liquid waste (HLLW). The as-prepared SiVpC adsorbent is characterized by SEM-EDS, TGA, and BET. The effects of nitric acidity, SiVpC adsorbent dosage, time, temperature, and palladium ion concentration on the adsorption are investigated. Among the 12 typical fission product metal ions (Ru, Rh, La, Y, Pr, Ce, Sm, Nd, Gd, Eu, Zr, Mo) existing in HLLW, SiVpC adsorbent can selectively adsorb palladium ( SF Pd/other metals = 137.6) in 0.5 M HNO 3 solution. The adsorptio kinetics of Pd(II) are consistent with the pseudo-second-order model, reaching equilibrium within 120 min. The maximum adsorption capacity is 38.4 mg/g in 0.5 M HNO 3 , and the adsorption process is consistent with the Langmuir model. The adsorbed palladium can be completely desorbed with 0.5 M HNO 3 -0.5 M Thiourea. Furthermore, SiVpC adsorbent remains good performance after five adsorption–desorption cycles, which indicates good reusability. The adsorption mechanism of SiVpC adsorbent on palladium is analyzed by FT-IR and XPS that N-containing functional groups on the ligand are coordinated with palladium, which is also further verified by DFT calculations. In addition, through the column chromatography separation system, SiVpC adsorbent can efficiently adsorb palladium from HLLW and the adsorbed palladium can be desorbed with 0.5 M HNO 3 -0.5 M thiourea solution, which has great application potential.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2024
·
IF 3.3
Jun-Feng Yang,Yun-Fei Liu,Lin-Lin Wei,Kai-Kai Qiao,Yan-Qiu Zhao,Lei Shi
The Minisci-type dehydrogenative coupling of N-heteroaromatic rings with inert C–H or Si–H partners via visible-light-catalyzed hydrogen atom transfer has been reported. This methodology allows the coupling reactions to be carried out in water as a solvent under air atmospheric conditions with visible-light illumination. A wide range of inert C–H and Si–H partners could be directly coupled with various N-aromatic heterocycles to deliver products in good to excellent yields.
研究领域:
有机化学
·
光化学
✓ 已验证
DOI
PubMed
高影响因子
ChemCatChem
·
2017
·Vol. 10
·期 4
·796-803
·
IF 4.803
Shi Feng,Xingyue Li,Jia Huo,Qiling Li,Chao Xie,Tingting Liu,Zhigang Liu,Zhenjun Wu,Shuangyin Wang
Graphical Porous carbon electrode : CoS 2 @N/S-codoped porous carbon is prepared through an electrodeposition–ZIF conversion–sulfuration strategy. The loading of active sites can be controlled easily by varying the electrodeposition time. The resulting material can be employed directly as a working electrode for the hydrogen evolution reaction and shows an excellent catalytic activity and stability. A convenient, controllable method to fabricate an electrode is necessary to achieve the practical application of a hydrogen evolution reaction (HER) catalyst. In this work, an electrodeposition–ZIF conversion–sulfuration strategy is developed to produce a CoS 2 @N/S-codoped porous carbon (CoS 2 @NSC/CFP) to drive the HER efficiently. CoS 2 @NSC/CFP was prepared by the electrodeposition of Co(OH) 2 on a carbon fiber paper followed by conversion into ZIF-67 and subsequent sulfuration with sulfur. The loading of electroactive components can be controlled easily in the range of 0.7–10.0 mg cm −2 by varying electrodeposition time from 5 min to 2 h. The resulting material can be employed directly as a working electrode for the HER and it shows an excellent catalytic activity and stability with an overpotential of 95 mV at 10 mA cm −2 and 158 mV to reach 100 mA cm −2 in an acidic medium. The high efficiency is related intimately to the high dispersion of ultra-small CoS 2 nanoparticles, heteroatom-codoping, and the 3 D porous network configuration of the carbon fiber paper.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Aling Chen,Qingfeng Yi,Kuang Sheng,Yuebing Wang,Jiangchuan Chen,Qiaoli Zhang,Kaiwen Xiang,Guanghua Tan
Development of high-efficiency oxygen reduction reaction (ORR) catalysts under neutral conditions has made little research progress. In this work, we synthesized a three-dimensional porous N/P codoped carbon nanosheet composites (CNP@PNS) by high-temperature thermal treatment of dicyandiamide, starch, and triphenylphosphine and subsequent porous structure-making treatment using the NaCl molten salt template. In the neutral solution, the electrocatalytic performance of the CNP@PNS-4 catalyst exhibits an onset potential of 0.98 V (vs reversible hydrogen electrode) and a half-wave potential of 0.91 V for ORR, which greatly surpasses commercial Pt/C (40%). Three kinds of neutral metal–air batteries (Zn–air, Al–air, and Fe–air) using the prepared samples as cathodic catalysts were constructed, corresponding to the maximum power density of 120.2, 78.3, and 18.9 mW·cm–2, respectively. Also, they reveal outstanding discharge stability under different current densities. The density functional theory calculation depicts the reduction of the free energy of the determining step and subsequent decline of the overpotential for ORR.
研究领域:
材料科学
·
电化学
·
能源科学
✓ 已验证
DOI
高影响因子
Environmental Science-Nano
·
2020
·Vol. 7
·期 12
·3814-3823
·
IF 7.683
Hanfeng Zhou,Zhibo Deng,Tianbao Liu,Tao Liu,Lijuan Zhang,Xintai Su,Zhang Lin
The science linking thermochemical conversion of large-scale industry oily sludge with applied materials has been improved in the last ten years. However, with the traditional converting methods it is hard to precisely control the composition and structure of oily sludge-based products during pyrolysis due to the complexity of the composition of the oily sludge. Here, a chlorinating calcination method using sodium chloride (NaCl) as a chlorinating salt and template was first developed to prepare porous Fe–N–C materials (FCN-500) through pyrolysis of oily sludge containing iron-bearing minerals and pyridine. The formation mechanism of FCN-500 was proposed, where iron ions (Fe3+) from the inorganic component (anorthite) in the sludge were rapidly dissociated with the assistance of NaCl, followed by coordination with the organic component (pyridine nitrogen) in the oily sludge to form the pyridine nitrogen–iron ((C5H6N)n–Fe) complex, and then carbonization. As-obtained FCN-500 exhibited higher specific capacitance (286.3 F g−1 at a current density of 0.5 A g−1), enhanced energy density (33.5 W h kg−1 at a power density of 606.1 W kg−1) and more excellent stability and durability (more than 80.1% capacitance retention after 10 000 cycles) compared with two other electrodes. The reasonably better performance of the obtained FCN-500 in supercapacitors (SCs) is attributed to its large surface area, hierarchically porous channels, high conductivity, and unique Fe–N–C structure. Therefore, this work not only provides a feasible way to solve the bottleneck problem in sludge pyrolysis, but also provides a method to design large scale porous Fe–N–C materials for practical applications.
研究领域:
环境科学
·
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Chun Bai,Kexin Li,Yanping Wang,Haining Liu,Huifang Zhang,Quan Li,Jun Li,Xiushen Ye,Zhijian Wu
ABSTRACT A novel boron flotation agent (N-2-hydroxyoctadecyl-N-Methylglucamine, NHO-NMDG) was fabricated using 1,2-epoxyoctadecane and N-methyl-D-glucamine. The obtained collector possesses both collecting and foaming properties and it was characterized by nuclear magnetic resonance, mass spectrometry, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy methods. The flotation performance for boron removal from the salt lake brine has been studied. The flotation experiments indicated a highly effective removal of boron from the salt lake brine. The boron removal rate in the Da Qaidam brine could reach 67.08% by NHO-NMDG. The mechanism analysis shows that the meglumine group in the bifunctional flotation agent can be complexed with boron, and the long-chain alkyl group can attach to the surface of the bubble and enter into the bubble layer, so as to separate boron from the aqueous solution.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Runren Jiang,Donghai Wu,Guanghua Lu,Zhenhua Yan,Jianchao Liu,Ranran Zhou,Matthew Nkoom
Herein, Fe 3 O 4 quantum dots modified BiOCl/BiVO 4 p-n heterojunction was successfully synthesized by a facile strategy. Multiple techniques were carried out to characterize the as-prepared samples. Results show that the photocatalysts possess regular crystal structure and consisted of BiOCl/BiVO 4 nanosheet structure with Fe 3 O 4 QDs on its surface. Particularly, 20% Fe 3 O 4 QDs@BiOCl/BiVO 4 p-n heterojunction shows universal outstanding photocatalytic activity for removing four different broad-spectrum antibiotics under visible light. Meanwhile, the mineralization degree and degradation pathways of antibiotic were further studied by 3D-EEMs and LC-MS/MS. The improved photocatalytic performance for degradation of broad-spectrum antibiotics mainly attributes to the effective charge carrier mobility, large specific surface areas, and strong visible light absorption. The photocatalytic reaction mechanism was also revealed by the electron spin resonance (ESR) technique and the active species trapping experiments. The photocatalyst stays stable crystal structures after four reaction cycles and it can be easily separated from the solution by an external magnetic field both demonstrate that the Fe 3 O 4 QDs@BiOCl/BiVO 4 p-n heterojunction has unlimited potential for practical usage. This work is expected to be widely applicable to the removal of broad-spectrum antibiotics.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Boyin Yan,Songxue Wang,Zhiquan Liu,Da Wang,Wenxin Shi,Fuyi Cui
In this work, the UV 254 /H 2 O 2 process was utilized to remove β-N-methylamino- l -alanine (BMAA), a kind of cyanobacteria neurotoxin, and the influence of reaction parameters and environmental factors on the degradation of BMAA has been systematically investigated. The results showed that BMAA could be effectively removed in the UV 254 /H 2 O 2 system compared to UV or H 2 O 2 alone and OH was confirmed as the main ROS to degrade BMAA. The degradation rate of BMAA increased first and then decreased with the increase of pH and the maximum k obs was 0.1545 min −1 obtained at pH 9. The removal of BMAA in the UV 254 /H 2 O 2 system was inhibited in actual water, while the degradation rate of BMAA in actual water could still exceed 90% by appropriately extending the reaction time. The decrease in the degradation efficiency of BMAA in actual water was primarily due to the ultraviolet light absorption and competition effects of NOM, and anions (Cl − and HCO 3 − ) would also inhibit the degradation of BMAA. Five by-products ([M − H] - = 118, 103, 88, 87 and 59) were identified in this study and the degradation pathways of BMAA were proposed. The production of by-products was attributed to the fracture of the C–N bond and hydroxylation reaction. This study is worthwhile to deepen the understanding of the degradation mechanism of BMAA in the UV 254 /H 2 O 2 system.
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
高影响因子
ACS Applied Engineering Materials
·
2023
·
IF 0
Demin Jiang,Kai Cheng,Liang Li,Kun Xie,Haijun Tao,Yuqiao Wang
Anodes are considered an important component of microbial fuel cells (MFCs) to recover electric energy from organic wastewater. Herein, Fe/N codoped paper carbon fiber foam was developed as an anode for MFCs to enhance electricity generation and wastewater treatment. The interconnected microporous network was beneficial for bacteria colonization and biofilm formation. The N doping enhanced the hydrophilicity to facilitate bacterial proximity. The Fe doping modulation adhered to the microorganisms due to the positive charge of iron ions. The codoped anode promoted the organic matter degradation efficiency and intrinsic electricity generation property based on the optimized thick biofilm. The high electricity output of MFCs was increased by the decreased internal resistance. The assembled MFCs possessed a short start-up time of 29.1 h, high maximum power density of 2270 ± 118 mW·m–2, desirable chemical oxygen demand removal efficiency of 71.7 ± 1.9%, and high decolorization efficiency of 90.3 ± 2.5% at 44 h. Fe/N codoped strategy is proposed to construct anodes for improving the electricity generation property and wastewater treatment efficiency of MFCs.
研究领域:
环境科学
·
生物电化学
·
材料科学
·
微生物学
✓ 已验证
DOI
RSC Advances
·
2020
·Vol. 10
·期 33
·19169-19177
·
IF 3.119
Biao Zhou,Bo Yang,Muhammad Waqas,Ke Xiao,Caizhen Zhu,Ling Wu
Constructing a 0D/3D p–n heterojunction is a feasible strategy for accelerating photo-induced charge separation and promoting photocatalytic H2 production. In this study, a 0D/3D MoS2/g-C3N4 (0D/3D-MCN) photocatalyst with a p–n heterojunction was prepared via a facile light-assisted deposition procedure, and the 3D spongy-like g-C3N4 (3D-CN) was synthesized through simple thermolysis of NH4Cl and melamine mixture. For comparison, 2D-MoS2 nanosheets were also embedded in 3D-CN by a solution impregnation method to synthesize a 2D/3D-MCN photocatalyst. As a result, the as-prepared 0D/3D-MCN-3.5% composite containing 3.5 wt% 0D-MoS2 QDs exhibited the highest photocatalytic H2 evolution rate of 817.1 μmol h−1 g−1, which was 1.9 and 19.4 times higher than that of 2D/3D-MCN-5% (containing 5 wt% 2D-MoS2 nanosheets) and 3D-CN, respectively. The results of XPS and electrochemical tests confirmed that a p–n heterojunction was formed in the 0D/3D-MCN-3.5% composite, which could accelerate the electron and hole movement in the opposite direction and retard their recombination; however, it was not found in 2D/3D-MCN-5%. This study revealed the relationship among the morphologies of MoS2 using g-C3N4 as a substrate, the formation of a p–n heterojunction, and the H2 evolution activity; and provided further insights into fabricating a 3D g-C3N4-based photocatalyst with a p–n heterojunction for photocatalytic H2 evolution.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）