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Novel strategies to tailor the photocatalytic activity of metal–organic frameworks for hydrogen generation: a mini-review

《能源前沿（英文）》页码 734-746 doi: 10.1007/s11708-022-0840-x

摘要： This review provides a recompilation of the most important and recent strategies employed to increase the efficiency of metal–organic framework (MOF)-based systems toward the photocatalytic hydrogen evolution (PHE) reaction through specific strategies: tailoring the photocatalytic activity of bare MOFs and guest@MOF composites, formation of heterojunctions based on MOFs and various photocatalysts, and inorganic photocatalysts derived from MOFs. According to the data reported in this mini-review, the most effective strategy to improve the PHE of MOFs relies on modifying the linkers with new secondary building units (SBUs). Although several reviews have investigated the photocatalytic activity of MOFs from a general point of view, many of these studies relate this activity to the physicochemical and catalytic properties of MOFs. However, they did not consider the interactions between the components of the photocatalytic material. This study highlights the effects of strength of the supramolecular interactions on the photocatalytic performance of bare and MOF-based materials during PHE. A thorough review and comparison of the results established that metal–nanoparticle@MOF composites have weak van der Waals forces between components, whereas heterostructures only interact with MOFs at the surface of bare materials. Regarding material derivatives from MOFs, we found that pyrolysis destroyed some beneficial properties of MOFs for PHE. Thus, we conclude that adding SBUs to organic linkers is the most efficient strategy to perform the PHE because the SBUs added to the MOFs promote synergy between the two materials through strong coordination bonds.

关键词： metal–organic frameworks (MOFs) photocatalytic hydrogen evolution MOF heterojunctions materials derived from MOFs bandgap recombination

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Crystalline porous materials: from zeolites to metal-organic frameworks (MOFs)

Zaiku Xie, Bao-Lian Su

《化学科学与工程前沿（英文）》 2020年第14卷第2期页码 123-126 doi: 10.1007/s11705-020-1921-1

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Ultrafine Fe-modulated Ni nanoparticles embedded within nitrogen-doped carbon from Zr-MOFs-confined conversion

《化学科学与工程前沿（英文）》 2022年第16卷第7期页码 1114-1124 doi: 10.1007/s11705-021-2087-1

摘要： Improvement of the low-cost transition metal electrocatalyst used in sluggish oxygen evolution reaction is a significant but challenging problem. In this study, ultrafine Fe-modulated Ni nanoparticles embedded in a porous Ni-doped carbon matrix were produced by the pyrolysis of zirconium metal-organic-frameworks, in which 2,2′-bipyridine-5,5′-dicarboxylate operating as a ligand can coordinate with Ni²⁺ and Fe³⁺. This strategy allows formation of Fe-modulated Ni nanoparticles with a uniform dimension of about 2 nm which can be ascribed to the spatial blocking effect of ZrO₂. This unique catalyst displays an efficient oxygen evolution reaction electrocatalytic activity with a low overpotential of 372 mV at 10 mA·cm^–2 and a small Tafel slope of 84.4 mV·dec^–1 in alkaline media. More importantly, it shows superior durability and structural stability after 43 h in a chronoamperometry test. Meanwhile, it shows excellent cycling stability during 4000 cyclic voltammetry cycles. This research offers a new insight into the construction of uniform nanoscale transition metals and their alloys as highly efficient and durable electrocatalysts.

关键词： metal-organic framework pyrolysis ultrafine Fe-modulated Ni nanoparticles oxygen evolution reaction

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A belated revelation: from gastroesophageal reflux derived asthma to laryngotracheal irritation even

WANG Zhonggao

《医学前沿（英文）》 2008年第2卷第2期页码 127-129 doi: 10.1007/s11684-008-0023-0

摘要： The author has been inspired by the Global Evidence-Based Consensus for gastroesophageal reflux (GER), which put forward four extra-esophageal syndromes: reflux cough syndrome, reflux laryngitis syndrome, reflux dental erosion syndrome and the reflux asthma syndrome. The author himself happened to receive five emergency rescue treatments following apparent “bronchial asthma”, which was to be diagnosed as GER at his own insistence. PPI resulted in some relief. After being rescued again from suffocation, he had a fundaplication, which was performed at the Englewood Hospital & Medical Center, Englewood, USA in March 2006. The procedure immediately cleared up his “asthma”. A month later he brought forth a Center for GER in an army hospital in Beijing, China. Up to now, 601 patients with mainly respiratory distress (84%) were treated by Stretta Radiofrequency, 58 by surgery and more by PPI. The GER Center is now complete with a ward. GER patients with respiratory distresses turned out to fare better than those with acid regurgitation. A nozzle-shaped pharynx was found in patients with the reflux. Animal study revealed that the refluxate entered into trachea and even lungs. Gradually a hypothesis of a gastro-oesophago-laryngo-tracheal reflux took shape.Our modest effort to treat GER-derived respiratory distresses has got off to an encouraging start amid relative shortage of experience and facilities. We would like to share two thoughts with scholars and experts at home and abroad:1. The GER-derived asthma is not asthma, but GER pure and simple;2. The pathogenesis of “asthma” is not asthma, but laryngotracheal irritation/spasm and its sequence.

关键词： laryngotracheal irritation/spasm gastro-oesophago-laryngo-tracheal sequence fundaplication encouraging

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Synthesis of magnetic carbonaceous acid derived from waste garlic peel for biodiesel production via esterification

《能源前沿（英文）》 doi: 10.1007/s11708-022-0836-6

摘要： Waste biomass-supported magnetic solid acids have particular advantages in catalyst separation. First, a novel magnetic carbonaceous catalyst was synthesized from waste garlic peel (GP) via in situ impregnation before conducting carbonization at 450–600°C and sulfonation at 105°C. The physical and chemical properties of the synthesized catalysts were characterized. It was found that the magnetism of the catalyst increased with the carbonization temperature. The optimized catalyst, carbonized at 600°C (C600-S), possessed an excellent magnetization value of 12.5 emu/g, with a specific surface area of 175.1 m²/g, a pore volume of 0.16 cm³/g, and an acidic property of 0.74 mmol/g -SO₃H density. By optimizing the esterification conditions to produce biodiesel, an oleic acid conversion of 94.5% was achieved at w(catalyst dosage) = 10% (w is mass fraction), a molar ratio of n(methanol): n(oleic acid) = 10: 1 (n is the amount of substance), and a reaction for 4 h at 90°C. Further, for catalyst regeneration, it was found that sulfuric acid treatment was more effective for improving the esterification activity than solvent washing, with which a conversion of more than 76% was achieved after the third run.

关键词： garlic peel (GP) magnetic carbonaceous acid esterification biodiesel

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Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen

《化学科学与工程前沿（英文）》 2021年第15卷第6期页码 1550-1560 doi: 10.1007/s11705-021-2104-4

摘要： The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy technologies. In this work, cobalt nanoparticle decorated N-doped carbons (Co@NC) are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert atmosphere. The Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles, indicating the important role of cobalt. The well-dispersed active sites (Co-N_x) and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction reaction. In addition, the Co content has a significant effect on the catalytic activity. The resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential (0.90 V), half-wave potential (0.80 V) and the limiting current density (4.84 mA·cm^–2), and a high selectivity, as well as a strong methanol tolerance and superior durability, these results are comparable to those of the Pt/C catalyst. Furthermore, the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built Zn-air battery, signifying the possibility for application in electrode materials and in current energy conversion and storage devices.

关键词： cobalt embedment N-doped carbons covalent organic framework oxygen reduction Zn-air battery

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Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated

《医学前沿（英文）》页码 68-74 doi: 10.1007/s11684-022-0955-9

摘要： Most information used to evaluate diabetic statuses is collected at a special time-point, such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk. As a new parameter for continuously evaluating personal clinical statuses, the newly developed technique “continuous glucose monitoring” (CGM) can characterize glucose dynamics. By calculating the complexity of glucose time series index (CGI) with refined composite multi-scale entropy analysis of the CGM data, the study showed for the first time that the complexity of glucose time series in subjects decreased gradually from normal glucose tolerance to impaired glucose regulation and then to type 2 diabetes (P for trend < 0.01). Furthermore, CGI was significantly associated with various parameters such as insulin sensitivity/secretion (all P < 0.01), and multiple linear stepwise regression showed that the disposition index, which reflects β-cell function after adjusting for insulin sensitivity, was the only independent factor correlated with CGI (P < 0.01). Our findings indicate that the CGI derived from the CGM data may serve as a novel marker to evaluate glucose homeostasis.

关键词： complexity of glucose time series continuous glucose monitoring impaired glucose regulation insulin secretion and sensitivity refined composite multi-scale entropy

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Bimetallic Ni-Fe catalysts derived from layered double hydroxides for CO methanation from syngas

Honggui Tang, Shuangshuang Li, Dandan Gong, Yi Guan, Yuan Liu

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 613-623 doi: 10.1007/s11705-017-1664-9

摘要： Carbon deposition and sintering of active components such as nano particles are great challenges for Ni-based catalysts for CO methanation to generate synthetic natural gas from syngas. Facing the challenges, bimetallic catalysts with different Fe content derived from layered double hydroxide containing Ni, Fe, Mg, Al elements were prepared by co-precipitation method. Nanoparticles of Ni-Fe alloy were supported on mixed oxides of aluminium and magnesium after calcination and reduction. The catalysts were characterized by Brunner-Emmett-Teller (BET), X-ray diffraction, hydrogen temperature programmed reduction, inductively coupled plasma, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric techniques, and their catalytic activity for CO methanation was investigated. The results show that the Ni-Fe alloy catalysts exhibit better catalytic performance than monometallic catalysts except for the Ni4Fe-red catalyst. The Ni2Fe-red catalyst shows the highest CO conversion (100% at 260–350 °C), as well as the highest CH selectivity (over 95% at 280–350 °C), owing to the formation of Ni-Fe alloy. In stability test, the Ni2Fe-red catalyst exhibits great improvement in both anti-sintering and resistance to carbon formation compared with the Ni0Fe-red catalyst. The strong interaction between Ni and Fe element in alloy and surface distribution of Fe element not only inhibits the sintering of nanoparticles but restrains the formation of Ni clusters.

关键词： methanation layered double hydroxide bimetal Ni-Fe alloy sintering carbon deposition

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adsorption and reduction of chromium(VI) to chromium(III) using nitrogen-doped porous carbon adsorbent derivedfrom loofah sponge

《环境科学与工程前沿（英文）》 2022年第16卷第5期 doi: 10.1007/s11783-021-1491-6

摘要：

• A high-efficiency N-doped porous carbon adsorbent for Cr(VI) was synthesized.

关键词： Chromium(VI) Nitrogen-doped porous carbon Adsorption Reduction Loofah sponge

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Electrospun porous carbon nanofibers derived from bio-based phenolic resins as free-standing electrodes

《化学科学与工程前沿（英文）》 doi: 10.1007/s11705-022-2260-1

摘要： Phenolic resins were employed to prepare electrospun porous carbon nanofibers with a high specific surface area as free-standing electrodes for high-performance supercapacitors. However, the sustainable development of conventional phenolic resin has been challenged by petroleum-based phenol and formaldehyde. Lignin with abundant phenolic hydroxyl groups is the main non-petroleum resource that can provide renewable aromatic compounds. Hence, lignin, phenol, and furfural were used to synthesize bio-based phenolic resins, and the activated carbon nanofibers were obtained by electrospinning and one-step carbonization activation. Fourier transform infrared and differential scanning calorimetry were used to characterize the structural and thermal properties. The results reveal that the apparent activation energy of the curing reaction is 89.21 kJ·mol^–1 and the reaction order is 0.78. The activated carbon nanofibers show a uniform diameter, specific surface area up to 1100 m²·g^–1, and total pore volume of 0.62 cm³·g^–1. The electrode demonstrates a specific capacitance of 238 F·g^–1 (0.1 A·g^–1) and good rate capability. The symmetric supercapacitor yields a high energy density of 26.39 W·h·kg^–1 at 100 W·kg^–1 and an excellent capacitance retention of 98% after 10000 cycles. These results confirm that the activated carbon nanofiber from bio-based phenolic resins can be applied as electrode material for high-performance supercapacitors.

关键词： lignin bio-based phenolic resins electrospinning activated carbon nanofibers supercapacitors

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Upgrading of derived pyrolysis vapors for the production of biofuels from corncobs

Liaoyuan Mao, Yanxin Li, Z. Conrad Zhang

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 50-58 doi: 10.1007/s11705-017-1685-4

摘要： A bubbling fluidized bed pyrolyzer was integrated with an honeycomb as a catalytic upgrading zone for the conversion of biomass to liquid fuels. In the upgrading zone, zeolite coated ceramic honeycomb (ZCCH) catalysts consisting of ZSM-5 (Si/Al=25) were stacked and N or recycled non-condensable gas was used as a carrier gas. Ground corncob particles were fast pyrolyzed in the bubbling bed using fine sand particles as a heat carrier and the resulting pyrolysis vapors were passed on-line over the catalytic upgrading zone. The influence of carrier gas, temperature, and weight hourly space velocity (WHSV) of catalyst on the oil product properties, distribution and mass balance were studied. Using ZCCH effectively increased the hydrocarbon yield and the heating value of the dry oil, especially in the presence of the recycled noncondensable gas. Even a low usage of zeolite catalyst at WSHV of 180 h was effective in upgrading the pyrolysis oil and other light olefins. The highest hydrocarbon (≥C2) and liquid aromatics yields reached to 14.23 and 4.17 wt-%, respectively. The undesirable products including light oxygenates, furans dramatically decreased in the presence of the ZCCH catalyst.

关键词： corncob monolith upgrading pyrolysis

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Preparation of starch esters with crosslinking structures derived from dianhydride

Huijuan CHU, Hongliang WEI, Jing ZHU, Shouyin HU

《化学科学与工程前沿（英文）》 2011年第5卷第1期页码 51-54 doi: 10.1007/s11705-010-0534-5

摘要： Starch is a kind of natural polymer used in many industrial fields because of its low cost, availability and biodegradation. Potato starch was modified by esterification with pyromellitic dianhydride, and the products were obtained with crosslinking structures. Orthogonal experiments showed that reactive temperature was the primary influencing factor. The product prepared at 40°C for 3 h with the mass ratio of starch and dianhydride of 16∶1 and pH value of 7.5 exhibited a degree of substitution of 11%. FTIR and UV analysis verified the formation of starch esters.

关键词： potato starch pyromellitic dianhydride esterification crosslink

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Characterization of value-added chemicals derived from the thermal hydrolysis and wet oxidation of sewage

Milan Malhotra, Anurag Garg

《环境科学与工程前沿（英文）》 2021年第15卷第1期 doi: 10.1007/s11783-020-1305-2

摘要： Abstract • Hydrothermal treatment can greatly improve resource recovery from sewage sludge. • tCOD removal during WO was ~55% compared with ~23% after TH. • TOC solubilization during hydrothermal treatment followed first-order kinetics. • Solids and carbon balance confirmed loss of organics during thermal hydrolysis. • Reaction pathways for thermal hydrolysis and wet oxidation are proposed. We evaluated the effect of hydrothermal pretreatments, i.e., thermal hydrolysis (TH) and wet oxidation (WO) on sewage sludge to promote resource recovery. The hydrothermal processes were performed under mild temperature conditions (140°C–180°C) in a high pressure reactor. The reaction in acidic environment (pH= 3.3) suppressed the formation of the color imparting undesirable Maillard’s compounds. The oxidative conditions resulted in higher volatile suspended solids (VSS) reduction (~90%) and chemical oxygen demand (COD) removal (~55%) whereas TH caused VSS and COD removals of ~65% and ~27%, respectively at a temperature of 180°C. During TH, the concentrations of carbohydrates and proteins in treated sludge were 400–1000 mg/L and 1500–2500 mg/L, respectively. Whereas, WO resulted in solids solubilization followed by oxidative degradation of organics into smaller molecular weight carboxylic acids such as acetic acid (~400–500 mg/L). Based on sludge transformation products generated during the hydrothermal pretreatments, simplified reaction pathways are predicted. Finally, the application of macromolecules (such as proteins), VFAs and nutrients present in the treated sludge are also discussed. The future study should focus on the development of economic recovery methods for various value-added compounds.

关键词： Hydrothermal pretreatment Reaction kinetics Reaction pathway Sewage sludge Thermal hydrolysis Wet oxidation

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Recycling Materials from Waste Electrical and Electronic Equipment

Jinhui Li

《环境科学与工程前沿（英文）》 2017年第11卷第5期 doi: 10.1007/s11783-017-1001-z

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Hierarchical porous carbon derived from one-step self-activation of zinc gluconate for symmetric supercapacitors

《化学科学与工程前沿（英文）》页码 387-394 doi: 10.1007/s11705-022-2250-3

摘要： Porous carbons with high specific area surfaces are promising electrode materials for supercapacitors. However, their production usually involves complex, time-consuming, and corrosive processes. Hence, a straightforward and effective strategy is presented for producing highly porous carbons via a self-activation procedure utilizing zinc gluconate as the precursor. The volatile nature of zinc at high temperatures gives the carbons a large specific surface area and an abundance of mesopores, which avoids the use of additional activators and templates. Consequently, the obtained porous carbon electrode delivers a satisfactory specific capacitance and outstanding cycling durability of 90.9% after 50000 cycles at 10 A∙g^–1. The symmetric supercapacitors assembled by the optimal electrodes exhibit an acceptable rate capability and a distinguished cycling stability in both aqueous and ionic liquid electrolytes. Accordingly, capacitance retention rates of 77.8% and 85.7% are achieved after 50000 cycles in aqueous alkaline electrolyte and 10000 cycles in ionic liquid electrolyte. Moreover, the symmetric supercapacitors deliver high energy/power densities of 49.8 W∙h∙kg^–1/2477.8 W∙kg^–1 in the Et₄NBF₄ electrolyte, outperforming the majority of previously reported porous carbon-based symmetric supercapacitors in ionic liquid electrolytes.

关键词： self-activation zinc organic salts abundant mesopores symmetric supercapacitor liquid electrolyte

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标题作者时间类型操作

Novel strategies to tailor the photocatalytic activity of metal–organic frameworks for hydrogen generation: a mini-review

期刊论文

Crystalline porous materials: from zeolites to metal-organic frameworks (MOFs)

Zaiku Xie, Bao-Lian Su

期刊论文

Ultrafine Fe-modulated Ni nanoparticles embedded within nitrogen-doped carbon from Zr-MOFs-confined conversion

期刊论文

A belated revelation: from gastroesophageal reflux derived asthma to laryngotracheal irritation even

WANG Zhonggao

期刊论文

Synthesis of magnetic carbonaceous acid derived from waste garlic peel for biodiesel production via esterification

期刊论文

Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen

期刊论文

Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated

期刊论文

Bimetallic Ni-Fe catalysts derived from layered double hydroxides for CO methanation from syngas

Honggui Tang, Shuangshuang Li, Dandan Gong, Yi Guan, Yuan Liu

期刊论文

adsorption and reduction of chromium(VI) to chromium(III) using nitrogen-doped porous carbon adsorbent derivedfrom loofah sponge

期刊论文

Electrospun porous carbon nanofibers derived from bio-based phenolic resins as free-standing electrodes

期刊论文

Upgrading of derived pyrolysis vapors for the production of biofuels from corncobs

Liaoyuan Mao, Yanxin Li, Z. Conrad Zhang

期刊论文

Preparation of starch esters with crosslinking structures derived from dianhydride

Huijuan CHU, Hongliang WEI, Jing ZHU, Shouyin HU

期刊论文

Characterization of value-added chemicals derived from the thermal hydrolysis and wet oxidation of sewage

Milan Malhotra, Anurag Garg

期刊论文

Recycling Materials from Waste Electrical and Electronic Equipment

Jinhui Li

期刊论文

Hierarchical porous carbon derived from one-step self-activation of zinc gluconate for symmetric supercapacitors

期刊论文

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