EUROPEAN POLYMER JOURNAL
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2022
·
IF 5.546
Ge Zhu,Haoji Lao,Feng Feng,Minyan Wang,Xingzhong Fang,Guofei Chen
Two series of poly(amide imide)s (PAIs) based on two novel isomeric amide-containing diamine monomers and different commercial aromatic dianhydrides were synthesized via thermal imidization. These PAIs exhibited excellent T g s ranging from 368 to 431 °C, low coefficients of thermal expansion (CTE) of 6.7–47.2 ppm/K, and good 5% weight loss temperatures ( T d5% s) in N 2 of 494–540 °C, which was attributed to the introduction of rigid backbone and strong intermolecular hydrogen bonding resulted from amide bond. In particular, PAI-1a and PAI-1b displayed well-balanced performance with T g s in the range of 419–431 °C, CTE in the range of 6.7–9.0 ppm/K, and mechanical properties with tensile strengths of 116–125 MPa, tensile moduli of 8.4–8.7 GPa, which could be probably used in flexible displays. In addition, the effects of two isomeric monomers on the properties of films were compared, and it was found that PAI-(1 – 3)a showed higher T g, T d5% and CTE, but lower tensile strength and transparency than PAI-(1 – 3)b .
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高影响因子
Batteries-Basel
·
2022
·Vol. 8
·期 10
·161
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IF 5.938
Han Wang,Sidra Jamil,Wenwen Tang,Jing Zhao,Hui Liu,Shujuan Bao,Yijun Liu,Maowen Xu
Due to the high theoretical capacity of 1675 mAh g−1of sulfur, lithium-sulfur (Li-S) batteries can reach a high energy density of 2600 Wh kg−1, which has shown fascinating potential in recent decades. Herein, we report the spiderweb-like nanocage (Co/Mel) as a novel sulfur host with a melamine-sacrificed pyrolysis method. The incorporation of embedded cobalt nanoparticles (Co NPs) in the tips of carbon nanotubes (CNTs) can catalyze polysulfide transformation kinetics. In addition, the nanocages form a conductive three-dimensional spiderweb-like network that facilitates electrolytic penetration and electronic/ionic transportation. Moreover, the porous internal nano-cavities not only improve sulfur loading levels but also provide buffer space for volume expansion during charging and discharging. As a result, the hollow Co/Mel polyhedra with a high content of sulfur (75.5 wt%) displays outstanding electrochemical performance with an initial discharge-specific capacity of 1425.2 mAh g−1at 0.1 C and a low decay rate of only 0.028% after 1000 cycles at 1 C.Keywords:lithium-sulfur batteries;pyrolytic synthesis;zeolite imidazolate framework;spiderweb-like nanocages;catalytic conversion
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APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Cai Xu,Liyan Dai,Yingqi Chen,Shaoyong Zhang,Chaozheng He,Xiaozhong Wang
WO 3 -WS 2 supported on mesoporous N, S co-doped carbon were prepared via one-step molten-salt strategy, and an enhanced interfacial interaction between metal and carbon was formed, which boosted the selective oxidation of benzyl alcohol to benzaldehyde. Under green conditions (solvent: H 2 O, oxidant: H 2 O 2 , no base-additives), 96.2 % conversion and 97.0 % selectivity were achieved within 2 h. It was found that N, S co-doped carbon with abundant mesopores served as an excellent support, the pyrrolic and graphitic N species of carbon provided main anchoring sites for metal nanoparticles. Additionally, the N, S co-doped carbon support could effectively promote the distribution of metal species, and thereafter induced the formation of metal–carbon interfacial interaction. Such advantages resulted in the satisfactory reusability (negligible activity loss after six cycles) and remarkable catalytic activity. The scavenger tests and EPR results disclosed that ·OH was the main oxidative species for this reaction. DFT calculations revealed that co-doping of N, S into carbon promoted the adsorption of benzyl alcohol, and the enhanced metal–carbon interaction reduced migration energy barrier of ·OH on catalyst surface. In sum, this work provided some new insights into the interfacial interaction of mesoporous carbon supported metal catalyst for boosting the selective oxidation of alcohols.
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JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Menglan Gao,Xiaobin Liao,Jing Yu,Xinna Lin,Huan Qi,Linlu Shen,Shupo Liu,Zhimin Yang
Bromide ions (Br - ) affected non-brominated nitroso-dimethylamine (NDMA) formation during ozonation , but the mechanism is still unclear. 1,1,1′,1′-tetramethyl-4,4′-(methylene-di- p -phenylene) di-semicarbazide (TMDS) was chosen to further probe this problem. The results indicated that low levels of Br - (≤20 μM) enhanced NDMA from 3.27 to 7.56 μg/L, while its amount slightly dropped to 6.22 μg/L raising Br - to 100 μM. It was experimentally verified that intermediates 1,1-dimethylsemicarbazide (DMSC) and 1,1-dimethylhydrazine (UDMH) played important roles on promoting NDMA generation, whose contribution rates were 40.2% and 32.2%, respectively. The brominated substances with higher NDMA molar yields were detected. ∙OH reduced NDMA formation without Br - , while it played promotion role with Br - ; the corresponding contribution rates were − 26.9% and 29.2%, respectively. No matter with or without Br - , both ∙O 2 - and l O 2 brought a boost to NDMA formation, their contribution ratios were 34.9% and 58.1% without Br - , while raised significantly to 64.6% and 81.5% when Br - existed. Br - not only facilitated NDMA formation, but also benefited the degradation of TMDS. Based on the calculation results and intermediates detected, the influence mechanisms of Br - were proposed. The results would provide theoretical basis and technical guarantee for treating NDMA precursors and bromide co-existing water in the future.
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高影响因子
CARBON
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2022
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IF 11.307
Min Yuan,Zeping Wang,Yifan Rao,Ying Wang,Bo Gao,Jiabing Yu,Hui Li,Xianping Chen
Carbon materials with multiple heteroatoms co-doping and hierarchically porous structures have attracted great attention as promising electrode-active materials for supercapacitors. In this paper, an efficient, green, and low-cost strategy is reported to produce O/N/S co-doped hierarchically porous graphene, using laser direct writing on carboxymethyl chitosan (CMCS)/sodium lignosulphonate (SLS) reinforced wood. The resultant materials possess a typical three-dimensional (3D) framework composed of interconnected micro-, meso- and macropores, a large specific surface area, together with rich heteroatoms doping (13.72 wt% for O, 2.06 wt% for N, and 1.68 wt% for S). These superior features have afforded the as-fabricated microsupercapacitor (MSC) with an excellent areal capacitance of 82.1 mF cm −2 at 0.1 mA cm −2 and correspondingly high energy density of 7.3 μWh cm −2 . Moreover, the MSC has good cycling stability (retaining 84.3% of capacitance after 10000 cycles) and favorable modular integration capabilities. Accordingly, this facile preparation of multiple heteroatoms-doped porous graphenes from various renewable and eco-friendly biomass precursors offers promising prospects for low-cost mass production of graphene-based sustainable high-performance electrochemical energy storage.
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APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jiabao Gu,Chaogang Ban,Jiazhi Meng,Qianwen Li,Xuanyu Long,Xiaohan Zhou,Nan Liu,Zequan Li
Rapid recombination of the photogenerated carrier, a limited range of photoexcitation, and unsatisfactory photocatalytic activity are the limiting factors in photocatalytic applications. Accelerating photogenerated carrier transfer and constructing surface active sites have become critical tasks. In this study, a dual Z-scheme UNiMOF/BiVO 4 /S-C 3 N 4 (NBSCN) photocatalyst with a 2D/3D/2D structure was successfully constructed. Under visible-light irradiation, NBSCN outperforms single and binary composites in photocatalytic tetracycline photodegradation and Cr(VI) photoreduction due to the synergistic effect of adsorption and photocatalysis. The maximum photocatalytic efficiency of tetracycline (90.1 %) and Cr(VI) (93.6 %) in 120 min was achieved by NBSCN-20 %. The exceptional photocatalytic activity of NBSCN-20 % can be attributed to the large specific surface area, increased active sites, improved visible-light absorption ranges, and the construction of heterojunctions. The fabricated dual Z-scheme heterojunction at the interface of NBSCN reduces the recombination rate of photogenerated carriers and widens the range of light absorption. NBSCN-20 % exhibits excellent stability in the process of cyclic experiments. On the basis of the results, the feasibility of the dual Z-scheme mechanism is proposed. This work demonstrates that NBSCN-20 % photocatalyst has promising application prospects in removing heavy-metal ions and organic pollutants from aqueous environments.
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ACS Sustainable Chemistry & Engineering
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2022
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IF 9.224
Lei Xiao,Chaowei Yuan,Peng Chen,Yongyi Liu,Jianping Sheng,Shihan Zhang,Fan Dong,Yanjuan Sun
Due to the intrinsic chemically inert CO2 with the dissociation energy of C═O bond as high as 750 kJ mol–1, low efficiency and selectivity have become the most significant restraints for the practical application of photocatalytic CO2 reduction. Renewing the electronic structure of adsorbed CO2 on the catalyst surface through a rational catalyst design is crucial to achieving performance improvement. Herein, we prepared ZnIn2S4 and Cu-substituted ZnIn2S4 containing both Lewis acid and Lewis base sites as a model system for investigating the activation of CO2 by M–S chemical bonds (M represents a metal site). The Cu–S chemical bond can effectively activate CO2 as a vital electron channel and lower the Gibbs free energy for generating the essential intermediate *COOH. Besides, the Cu0.7-ZnIn2S4 sample displays 74.8% selectivity for reducing CO2 to CO with a rate of 47.2 μmol g–1 h–1, roughly 7.14 times that of ZnIn2S4.
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高影响因子
FUEL
·
2022
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IF 8.035
Baicheng Feng,Zichen Zhang,Jiaqiang Wang,Donglin Yang,Qun Li,Yaping Liu,Hengjun Gai,Tingting Huang,Hongbing Song
The catalytic hydrogenation of carbon dioxide (CO 2 ) into formic acid is among the most important reactions to alleviate global warming and realize the carbon cycle. How to achieve rapid activation of CO 2 remains a challenge. In this work, we designed two novel hydrophobic poly(ionic liquid)s (PILs) with a good affinity for CO 2 . Since the abundant N atoms in the PILs can anchor palladium (Pd) nanoparticles, the designed catalyst can rapidly activate CO 2 and H 2 simultaneously, thus efficiently catalyzing the hydrogenation of CO 2 to formic acid under mild conditions. Due to the synergy from the bis(trifluoromethanesulfonyl)amide anion ([Tf 2 N − ]) with strong hydrophobicity and CO 2 affinity and trimethylamine (NEt 3 ) as a low dissociation energy alkaline additive, the resultant Pd/PIL-bip-Tf 2 N exhibited the best catalytic performance on the hydrogenation of CO 2 to formic acid. The TOF value reached 1,190 h −1 in the aqueous solution of NEt 3 at 100 °C, 1 h, and a total pressure of 4 MPa. The activation energy and dissociation energy during the catalytic process were calculated by DFT, indicating that the synergistic effect of NEt 3 is better than that of other alkaline additives. In addition, the catalytic activity of the catalyst remained stable after several cycling experiments. Based on the obtained results, we proposed a possible reaction pathway. Therefore, PILs have great potential as catalyst carrier material for CO 2 hydrogenation.
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Nanomaterials
·
2022
·Vol. 12
·期 12
·2079
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IF 5.719
Dong Li,Fachao Wu,Caiyun Gao,Hongfang Shen,Fei Han,Fenglan Han,Zhanlin Chen
In this work, a highly efficient wide-visible-light-driven photoanode, namely, nitrogen and sulfur co-doped tungsten trioxide (S-N-WO3), was synthesized using tungstic acid (H2WO4) as W source and ammonium sulfide ((NH4)2S), which functioned simultaneously as a sulfur source and as a nitrogen source for the co-doping of nitrogen and sulfur. The EDS and XPS results indicated that the controllable formation of either N-doped WO3(N-WO3) or S-N-WO3by changing the nW:n(NH4)2Sratio below or above 1:5. Both N and S contents increased when increasing the nW:n(NH4)2Sratio from 1:0 to 1:15 and thereafter decreased up to 1:25. The UV-visible diffuse reflectance spectra (DRS) of S-N-WO3exhibited a significant redshift of the absorption edge with new shoulders appearing at 470–650 nm, which became more intense as the nW:n(NH4)2Sratio increased from 1:5 and then decreased up to 1:25, with the maximum at 1:15. The values of nW:n(NH4)2Sratio dependence is consistent with the cases of the S and N contents. This suggests that S and N co-doped into the WO3lattice are responsible for the considerable redshift in the absorption edge, with a new shoulder appearing at 470–650 nm owing to the intrabandgap formation above the valence band (VB) edge and a dopant energy level below the conduction band (CB) of WO3. Therefore, benefiting from the S and N co-doping, the S-N-WO3photoanode generated a photoanodic current under visible light irradiation below 580 nm due to the photoelectrochemical (PEC) water oxidation, compared with pure WO3doing so below 470 nm.Keywords:N, S co-doped;water oxidation;tungsten trioxide;photoanode;photoelectrochemical;water splitting
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高影响因子
CARBON
·
2022
·
IF 11.307
Wenjie Wei,Fenghong Lu,Lixiu Cui,Yu Zhang,Yanze Wei,Lingbo Zong
Tuning of the coordination environment of atomically dispersed single atoms (SAs) by heteroatom doping is a promising strategy to boost the electrocatalytic activity for oxygen reduction reaction (ORR). The synergistic effect of dual heteroatom doping provides additional degrees of freedom to achieve higher ORR efficiency through decreased energy barriers of the intermediates in catalytic processes. Herein, Fe–SAs anchored within the N, S co-doped porous nanosized carbonaceous spheres (Fe–SAs@N/S-PCSs) was fabricated through the pyrolysis of anchored heteroatom sources and ferric precursors. Under the low catalyst loading capacity of 0.255 mg cm −2 , the obtained Fe–SAs@N/S-PCSs exhibits exceptionally high performance with ORR onset potential (E onset ) of 1.02 V, and half wave potential (E 1/2 ) of 0.90 V (vs. RHE) in 0.1 M KOH solution, outperforming benchmark Pt/C (E onset = 1.01 V, E 1/2 = 0.86 V). Superior oxygen evolution reaction (OER) activity (450 mV at 10 mA cm −2 ) is also demonstrated, thus displaying outstanding performance for Zn-air battery. The porous structure , rich accessible Fe SAs, and the optimal binding of ORR-related species induced by S doping in carbon matrix generate the excellent ORR activity and durability. This work provides insights into the rational design of cost-effective single atom catalysts (SACs) with impressive electrocatalytic activities for efficient energy conversion applications.
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JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 28
·13527-13540
·
IF 4.682
Chen Dongli,Zhu Ming,Zhan Wenwei,Long Lei,Yu Lu,Zhu Tao,Kang Peibin,Yang Xiaoping,Sui Gang
Abstract Lithium–sulfur (Li–S) batteries have been considered as a promising substitute for lithium-ion batteries because of their high theoretical specific capacity, low cost, and environmental friendliness. However, the further practical application of Li–S batteries is greatly limited by the intrinsic insulation of sulfur, the shuttle effects of polysulfides and sluggish kinetics of the redox reaction. Herein, a well-designed Fe, N co-doped mesoporous carbon sphere (Fe-N-MCS) was fabricated to modify separator for absorbing and reutilizing polysulfides in high-performance Li–S batteries using cost-effective S cathode. The obtained Fe-N-MCS was not only acted as a physical barrier layer to block polysulfides, but also as trapper to capture and anchor polysulfides due to its highly porous structure and N dopants in the carbon frameworks. Furthermore, the high-conductive Fe-N-MCS barrier layer can facilitate electron and ion transfer to improve the electrochemical reutilization of polysulfide trapped therein, because the Fe-N-MCSs exhibited high catalytic activity for enormously boosting the redox kinetics of polysulfides. In consequence, the Li–S batteries with Fe-N-MCS modified separator exhibited high reversible capacity, superior rate capability and impressively cycling stability. The construction of non-precious metal barrier layer with catalyst activity is a promising pathway for the development of high-energy–density Li–S batteries. Graphical abstract The polysulfides were anchored and reutilized by the Fe-N-MCS layer for high-performance lithium sulfur battery.
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CHEMOSPHERE
·
2022
·
IF 8.943
Zhihong Li,Danquan Lan,Zuji Li,Jiangli Sun,Shuo Chen,Jinhang Yang,Jingwen Wei,Zebing Yu,Shuangfei Wang,Yanping Hou
Development of efficient photocatalysts for efficient recalcitrant organic pollutants degradation is of great significance. Herein, the step-doped disulfide vacancies S-scheme Cu 3 SnS 4 /L-BiOBr (CTS/L-BiOBr) heterojunction photocatalyst was prepared for ciprofloxacin (CIP) degradation. X-ray photoelectron spectroscopy (XPS) analysis, ultraviolet photo-electron spectroscopy (UPS) analysis, band structure and dominant radicals’ identification together verified that the transfer of photogenerated carriers conformed to the S-scheme mechanism. Benefited from the interfacial electric field (IEF) of the S-scheme heterojunction and incorporation of L-cysteine with introducing S-vacancies and surface functional groups (-NH 2 , -COO - ), photogenerated charges generation and separation of the CTS/L-BiOBr (10) were greatly improved. With ·OH and h + as dominant reactive species, CIP removal reached 93% using CTS/L-BiOBr (10) within 180 min of visible light irradiation, which was 3.5 times and 2.6 times of pristine Cu 3 SnS 4 and L-BiOBr, respectively. Moreover, possible CIP degradation pathways were proposed and the degradation intermediates ecotoxicity were evaluated. This study could provide reference for designing efficient S-scheme photocatalysts for recalcitrant wastewater treatment .
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高影响因子
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