An effective and environmentally benign benzylic oxidation for transition of alkylarenes into the corresponding carbonyl compounds was reported. Alkylarenes were mixed and stirred with potassium bromide, m-chloroperbe...An effective and environmentally benign benzylic oxidation for transition of alkylarenes into the corresponding carbonyl compounds was reported. Alkylarenes were mixed and stirred with potassium bromide, m-chloroperbenzoic acid and a catalytic amount of iodobenzene in water at 60 ℃ for several hours, a series of the corresponding carbonyl compounds was obtained in moderate to good yields. In the reaction, iodobenzene was first oxidized by m-chloroperbenzoic acid into the hypervalent iodine intermediate which then reacted with potassium bromide to form the key radical initiator for the benzylic oxidation.展开更多
A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly（1,4-phenylene-2,5-pyridine dicarboxyamide）. This polymeric reagent was used for the selective oxidation of primary benzylic alcohols...A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly（1,4-phenylene-2,5-pyridine dicarboxyamide）. This polymeric reagent was used for the selective oxidation of primary benzylic alcohols to the corresponding benzaldehydes in CH_3CN at reflux conditions.Excellent selectivity was observed between primary benzyl alcohols and secondary ones as well as non-benzylic alcohols in the oxidation reactions.Allylic alcohols were also converted to the corresponding aldehydes with good yields.展开更多
Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely bee...Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely been produced through the modulation of their structure and composition.In this study,a series of bimetallic nickel-iron phosphide(Ni_(x)Fe_(2-x)P,where 0<x<2)cocatalysts with controllable structures and overpotentials were designed by adjusting the atomic ratio of Ni/Fe onto nonmetallic elemental red phosphorus(RP)for the photocatalytic selective oxidation of benzyl alcohol(BA)coupled with hydrogen production.The catalysts exhibited an outstanding photocatalytic activity for benzaldehyde and a high H_(2)yield.The RP regulated by bimetallic phosphide cocatalysts(Ni_(x)Fe_(2-x)P)demonstrated higher photocatalytic oxidation-reduction activity than that regulated by monometallic phosphide cocatalysts(Ni_(2)P and Fe2P).In particular,the RP regulated by Ni_(1.25)Fe_(0.75)P exhibited the best photocatalytic performance.In addition,experimental and theoretical calculations further illustrated that Ni_(1.25)Fe_(0.75)P,with the optimized electronic structure,possessed good electrical conductivity and provided strong adsorption and abundant active sites,thereby accelerating electron migration and lowering the reaction energy barrier of RP.This finding offers valuable insights into the rational design of highly effective cocatalysts aimed at optimizing the photocatalytic activity of composite photocatalysts.展开更多
The development of efficient photocatalysts for selective organic transformations under visible light remains a major challenge in sustainable chemistry.In this study,we present a straightforward solvothermal strategy...The development of efficient photocatalysts for selective organic transformations under visible light remains a major challenge in sustainable chemistry.In this study,we present a straightforward solvothermal strategy for fabricating a defect-engineered ZrO_(2)/UiO-66-NH_(2)hybrid material with abundant oxygen vacancies,enabling the visible-light-driven oxidation of benzyl alcohol to benzaldehyde.By optimizing the solvothermal treatment duration,the composite(UiO-66-NH_(2)-2h)achieves a 74.1%conversion of benzyl alcohol with>99%selectivity toward benzaldehyde under mild conditions,substantially out-performing pristine UiO-66-NH_(2).Structural and mechanistic studies reveal that the solvothermal process induces the in situ formation of ultrasmall,uniformly dispersed ZrO_(2)nanoparticles(~2.3 nm)within the MOF matrix,while simultaneously generating abundant oxygen vacancies,as confirmed by XPS,EPR,and HRTEM analyses.The defect-mediated electronic structure of the ZrO_(2)/UiO-66-NH_(2)hybrid enhances visible-light absorption,facilitates charge carrier separation,and pro-motes efficient activation of O_(2)into superoxide radicals(·O_(2)^(−)),the primary reactive species.Transient photocurrent measure-ments and electrochemical impedance spectroscopy further verify the improved charge separation efficiency.The synergistic interplay between oxygen vacancies and the intimate ZrO_(2)/UiO-66-NH_(2)interface provides a unique defect-mediated charge transfer pathway,distinguishing this system from conventional heterojunctions.This study demonstrates a facile,one-step approach to integrate defect engineering with interfacial hybridization in MOF-based photocatalysts,off ering a scalable route for solar-driven organic synthesis.展开更多
Various manganese oxide nanorods with similar one-dimensional morphology were prepared by calcination of MnOOH nanorods under different gas atmosphere and at different temper- atures, which were synthesized by a hydro...Various manganese oxide nanorods with similar one-dimensional morphology were prepared by calcination of MnOOH nanorods under different gas atmosphere and at different temper- atures, which were synthesized by a hydrothermal route. The morphology and structure of MnOx catalysts were characterized by a series of techniques including X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and tempera- ture programmed reduction （TPR）. The catalytic activities of the prepared MnO~ nanorods were tested in the liquid phase aerobic oxidation of benzyl alcohol, which follow a sequence as MnO2〉Mn203~Mn304〉MnOOH with benzaldehyde being the main product. On the basis of H2-TPR results, the superior activity of MnO2 is ascribed to its lower reduction temperature and therefore high oxygen mobility and excellent redox ability. Moreover, a good recycling ability was observed over MnO2 catalysts by simply thermal treatment in air.展开更多
The water promotion effects,where water can provide a solution-mediated reaction pathway in various heterogeneous chemical catalysis,have been presented and attracted wide attention recently,yet,the rational design of...The water promotion effects,where water can provide a solution-mediated reaction pathway in various heterogeneous chemical catalysis,have been presented and attracted wide attention recently,yet,the rational design of catalysts with a certain ability of enhancing water-induced reaction process is full of challenges and difficulties.Here,we show that by incorporating alkali(Na,K)cations as an electronic and/or structural promoter into Pd/rGO-ZnCr_(2)O_(4)(r GO,reduced graphene oxide),the obtained Pd(Na)/rGO-ZnCr_(2)O_(4)as a representative example demonstrates an outstanding benzyl alcohol oxidation activity in the Pickering emulsion system in comparison to the alkali-free counterpart.The response experiments of water injection confirm the enhanced activity,and the Na-modified catalyst can further enhance the promotion effects of water on the reaction.The effects of alkali cations for Pd nanoparticles are identified and deciphered by a series of experimental characterizations(XPS,in situ CO-DRIFTS,and CO-TPR coupled with MS),showing that there is abundant-OH on the surface of the catalyst,which is stabilized by the formation of Pd-OH_(x).The alkali-stabilized Pd-OH_(x)is helpful to enhance the waterinduced reaction process.According to the results of in situ Raman as well as UV-vis absorption spectra,the Na-modulated Pd(Na)/rGO-ZnCr_(2)O_(4)enables the beneficial characteristics for distorting the benzyl alcohol structure and enhancing the adsorption of benzyl alcohol.Further,the mechanism for enhanced water promotion effects is rationally proposed.The strategy of alkali cations-modified catalysts can provide a new direction to effectively enhance the chemical reaction involving small molecule water.展开更多
Ferric acetylacetonate/covalent organic framework(Fe(acac)_(3)/COF)composite was synthesized by interfacial polymerization method at room temperature.The crystal structure,morphology and porosity property of the compo...Ferric acetylacetonate/covalent organic framework(Fe(acac)_(3)/COF)composite was synthesized by interfacial polymerization method at room temperature.The crystal structure,morphology and porosity property of the composite were characterized by X-ray diffraction,scanning electron microscope,transmission electron microscope and nitrogen adsorption.The interaction between Fe(acac)_(3) and COF was investigated by Fourier transform infrared spectra and X-ray photoelectron spectroscopy.The Fe(acac)_(3)/COF composite was used as a photocatalyst for the oxidation of benzyl alcohol under mild conditions.It exhibits high activity and selectivity for the reaction,of which the mechanism was investigated by determining its photoelectric properties.The Fe(acac)_(3)/COF catalyst developed in this work has application potential in other photocatalytic reactions.展开更多
Various Au/GO catalysts were prepared by depositing Au nanoparticles on thermally- and chemically-treated graphite oxide （GO） supports using a sol-immobilization method. The surface chemistry and structure of GO sup...Various Au/GO catalysts were prepared by depositing Au nanoparticles on thermally- and chemically-treated graphite oxide （GO） supports using a sol-immobilization method. The surface chemistry and structure of GO supports were characterized by a series of analytical techniques including X-ray photoelectron spectroscopy, temperature-programmed desorption and Raman spectroscopy. The results show that thermal and chemical treatments have large influence on the presence of surface oxygenated groups and the crystalline structure of GO supports. A strong support effect was observed on the catalytic activity of Au/GO catalysts in the liquid phase aerobic oxidation of benzyl alcohol. Compared to the amount and the type of surface oxygen functional groups, the ordered structure of GO supports may play a more important role in determining the catalytic performance of Au/GO catalysts.展开更多
Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively ...Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions.Herein,aza-fused7 r-conjugated microporous polymer(aza-CMP)with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation.The AuPd nanoparticles anchored on aza-CMP(aza-CM P/Au_xPdy)exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm^2 light irradiation.The improved catalytic performance by the aza-CMP/Au_xPdy is attributed to the unique photothermal effect induced by aza-CMP,which can promote the catalytic benzyl alcohol oxidation occurring at Au Pd.This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect.展开更多
A novel magnetically recoverable thioporphyrazine catalyst（CoPz（S-Bu）8/SiO2@Fe3O4） was prepared by immobilization of the cobalt octkis（butylthio） porphyrazine complex（CoPz（S-Bu）8） on silica-coated magnetic n...A novel magnetically recoverable thioporphyrazine catalyst（CoPz（S-Bu）8/SiO2@Fe3O4） was prepared by immobilization of the cobalt octkis（butylthio） porphyrazine complex（CoPz（S-Bu）8） on silica-coated magnetic nanospheres（SiO2@Fe3O4）. The composite CoPz（S-Bu）8/SiO2@Fe3O4appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide（H2O2） as oxidant under Xe-lamp irradiation,with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number（TON） of 61.7 at ambient temperature. The biomimetic catalyst CoPz（S-Bu）8was supported on the magnetic carrier SiO2@Fe3O4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz（S-Bu）8can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications.展开更多
Homojunction engineering is a promising modification strategy to improve charge carrier separation and photocatalytic performance of carbon nitrides.Leveraging intrinsic heptazine/triazine phase and face-to-face conta...Homojunction engineering is a promising modification strategy to improve charge carrier separation and photocatalytic performance of carbon nitrides.Leveraging intrinsic heptazine/triazine phase and face-to-face contact,crystalline C_(3)N_(5)(CC3N5)was combined with protonated g-C_(3)N_(4)(pgCN)through electrostatic self-assembly to achieve robust 2D/2D homojunction interfaces.The highest photocatalytic performance was obtained through crystallinity and homojunction engineering,by controlling the pgCN:CC3N5 ratio.The 25:100 pgCN:CC3N5 homo-junction(25CgCN)had the highest hydrogen production(1409.51 μmol h^(-1))and apparent quantum efficiency(25.04%,420 nm),8-fold and 180-fold higher than CC3N5 and pgCN,respectively.This photocatalytic homojunction improves benzaldehyde and hydrogen production activity,retaining 89%performance after 3 cycles(12 h)on a 3D-printed substrate.Electron paramagnetic resonance demonstrated higher·OH,·O_(2) and hole production of irradiated 25CgCN,attributed to crystallinity and homojunction interaction.Thus,electrostatic self-assembly to couple CC3N5 and pgCN in a 2D/2D homojunction interface ameliorates the performance of multifunctional solar-driven applications.展开更多
By harnessing the power of MoS_(2) as a cocatalyst to enhance electron transfer and charge carrier separation,a groundbreaking two-in-one redox photocatalytic system was developed.This innovative system integrated 2D ...By harnessing the power of MoS_(2) as a cocatalyst to enhance electron transfer and charge carrier separation,a groundbreaking two-in-one redox photocatalytic system was developed.This innovative system integrated 2D MoS_(2) nanosheets onto hydrangea-like Zn_(3)In_(2)S_(6) nanosheets,forming a 2D/3D heterostructure that established a stable and intimate interface.This unique architecture significantly improved cooperative photocatalytic performance,enabling the simultaneous production of hydrogen and benzaldehyde under light irradiation≥420 nm.Notably,the system achieved remarkable yields of hydrogen(41.9 mmol g^(-1) h^(-1))and benzaldehyde(38.9 mmol g^(-1) h^(-1)),surpassing the pristine Zn_(3)In_(2)S_(6) by 22.4 times.An impressive electron-hole pair utilization rate of approximately 93%was attained,underscoring the high efficiency of this two-in-one redox system.Additionally,the targeted 10 wt%-MoS_(2) loaded Zn_(3)In_(2)S_(6)(10MZ)nanohybrids at 400 nm obtained an apparent quantum yield(AQY)value of 17.66%without sacrificial agents or noble metals.The exceptional performance was attributed to improved charge carrier separation and reduced recombination,facilitated by cocatalyst integration and evidenced via photoluminescence,photoelectrochemical and Kelvin probe force microscopy measurements.This work highlighted the critical role of two-in-one redox-functioning heterojunctions in optimizing electron-hole pair utilization,offering a promising approach for sustainable energy production and organic synthesis.By demonstrating the potential for efficient,simultaneous generation of valuable chemicals and fuels,this research paves the way for the development of next-generation photocatalytic systems.展开更多
Despite advances in photocatalytic half-reduction reactions,challenges remain in effectively utilizing electron-hole pairs in concurrent redox processes.The present study involved the construction of a p-n junction Co...Despite advances in photocatalytic half-reduction reactions,challenges remain in effectively utilizing electron-hole pairs in concurrent redox processes.The present study involved the construction of a p-n junction Co_(3)O_(4)/Zn_(3)In_(2)S_(6)(CoZ)hybrid with a complementary band edge potential.The photocatalyst formed by the 2D assembled-nanostructure portrayed an optimal yield of 13.8(H_(2))and 13.1(benzaldehyde)mmol g^(-1)h^(-1)when exposed to light(λ>420 nm),surpassing 1%Pt-added ZIS(12.4(H_(2))and 10.71(benzaldehyde)mmol g^(-1)h^(-1)).Around 95%of the electron-hole utilization rate was achieved.The solar-to-hydrogen(STH)and apparent quantum yield(AQY)values of 0.466%and 4.96%(420nm)achieved by this system in the absence of sacrificial agents exceeded those of previous works.The exceptional performance was mostly ascribed to the synergistic development of adjoining p-n heterojunctions and the built-in electric field for effective charge separation.Moreover,scavenger studies elucidated the intricate mechanistic enigma of the dual-redox process,in which benzaldehyde was produced via O-H activation and subsequent C-H cleavage of benzyl alcohol over CoZ hybrids.Furthermore,the widespread use of the optimal 1-CoZ composites was confirmed in multiple photoredox systems.This work presents an innovative perspective on the construction of dual-functioning p-n heterojunctions for practical photoredox applications.展开更多
We have developed a chemo-and site-selective aerobic oxidation of methylbenzenes to aromatic aldehydes.It offers several advantages,including the use of an environmentally friendly catalyst(5 mol%of inexpensive ferric...We have developed a chemo-and site-selective aerobic oxidation of methylbenzenes to aromatic aldehydes.It offers several advantages,including the use of an environmentally friendly catalyst(5 mol%of inexpensive ferric chloride hexahydrate),the utilization of air as a green oxidant,mild conditions,scalability(up to 5 g scale),and operational simplicity.Furthermore,the reaction demonstrates remarkable chemo-selectivity and site-selectivity.This is evident from the lack of over-oxidation leading to carboxylic acids.Additionally,the reaction effectively converts substrates with multiple methyl groups into mono-aromatic aldehydes.The synthetic potential of this approach lies in the ability to modify complex molecules at a late stage,and conversion of inexpensive compounds into high-value fine chemicals.We expect that these characteristics will facilitate the widespread adoption of this reaction in future applications.展开更多
Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and conversion.Herein,a ...Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and conversion.Herein,a facile strategy was explored for preparing a hierarchical porous heterostructure of Fe_(4)Ni_(5)S_(8)@ZnIn_(2)S_(4)(FNS@ZIS)by the in situ growth of ZIS nanosheets on Prussian blue analogue(PBA)-derived bimetallic FNS sulfides.A series of FNS@ZIS hierarchical structures were facilely prepared by adjusting the loading amount(n%)of FNS(n=19,26,and 32 for FNS@ZIS-1-3).These structures can efficiently drive the solar co-production of H_(2) and organic chemicals.The optimal co-production was achieved with FNS@ZIS-2,affording a H_(2) evolution rate of 10465μmol·g^(-1)·h^(-1),along with high selectivity for the oxidation of benzyl alcohol to benzaldehyde(>99.9%).The performance was 22 and 31 times higher than that of FNS and ZIS,respectively,and even superior to the state-of-the-art results achieved using various sacrificial agents.Further mechanistic study indicated that the unique hierarchical core/shell architecture can facilitate interfacial charge separation,afford bimetallic synergy,abundant active sites and excellent photostability.This work highlights a simple and efficient method for preparing porous multimetallic hierarchical structures for the solar co-production of organic chemicals and H_(2) fuel.展开更多
Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Micro...Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
Simultaneous generation of H_(2) fuel and value-added chemicals has attracted increasing attention since the photogenerated electrons and holes can be both employed to convert solar light into chemical energy.Herein,f...Simultaneous generation of H_(2) fuel and value-added chemicals has attracted increasing attention since the photogenerated electrons and holes can be both employed to convert solar light into chemical energy.Herein,for realizing UV-visible-NIR light driven dehydrogenation of benzyl alcohol(BA)into benzaldehydes(BAD)and H_(2),a novel localized surface plasmon resonance(LSPR)enhanced S-scheme heterojunction was designed by combining noble-metal-free plasmon MoO_(3-x) as oxidation semiconductor and Zn_(0.1)Cd_(0.9)S as reduction semiconductor.The photoredox system of Zn_(0.1)Cd_(0.9)S/MoO_(3-x) displayed an unconventional reaction model,in which the BA served as both electron donor and acceptor.The S-scheme charge transfer mechanism induced by the formed internal electric field enhanced the redox ability of charge carriers thermodynamically and boosted charge separation kinetically.Moreover,due to the LSPR effect of MoO_(3-x) nanosheets,Zn_(0.1)Cd_(0.9)S/MoO_(3-x) photocatalysts exhibited strong absorption in the region of full solar spectrum.Therefore,the Zn_(0.1)Cd_(0.9)S/MoO_(3-x) composite generated H_(2) and BAD simultaneously via selective oxidation of BA with high production(34.38 and 33.83 mmol×g^(–1) for H_(2) and BAD,respectively)upon full solar illumination.Even under NIR light irradiation,the H_(2) production rate could up to 94.5 mmol×g^(–1)×h^(–1).In addition,the Zn_(0.1)Cd_(0.9)S/MoO_(3-x) composite displayed effective photocatalytic H_(2) evolution rate up to 149.2 mmol×g^(–1)×h^(–1) from water,which was approximate 6 times that of pure Zn_(0.1)Cd_(0.9)S.This work provides a reference for rational design of plasmonic S-scheme heterojunction photocatalysts for coproduction of high-value chemicals and solar fuel production.展开更多
Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols ...Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols and the dibromination of unsaturated hydrocarbons.This chemical process carries substantial research significance in the field of organic synthesis.In this study,two types of triaryl phosphine oxides and benzyl diaryl phosphine oxides containing alkyne groups were designed and synthesized.These compounds were then subjected to reaction with oxalyl bromide,resulting in the formation of novel benzophosphonium tribromides and trans-phosphoryl dibromoalkenes,respectively.These findings demonstrate variations from their reactions with oxalyl chloride.Furthermore,the benzophosphonium tribromide obtained can act as an alternative reagent for bromine,enabling the direct bromination of aromatics compounds,olefin,alkyne and acetophenone derivatives.展开更多
Active oxygen radicals(OH^(*)/O^(*)/OOH^(*))generated from oxygen evolution reaction(OER)play a crucial role in facilitating the electrooxidation of organic compounds into high value-added chemicals.However,constructi...Active oxygen radicals(OH^(*)/O^(*)/OOH^(*))generated from oxygen evolution reaction(OER)play a crucial role in facilitating the electrooxidation of organic compounds into high value-added chemicals.However,constructing atomically precise active sites with a specific function to catalyze water-coupled electrooxidation reactions in a tandem system still confronts a great challenge.Herein,we propose a novel water-participating benzyl alcohol electrooxidation tandem process by constructing homogeneous isolated Fe-Pt dual-atom site catalysts on CoOOH nanosheet arrays(FePt DAC).The Fe and Pt dual atomic sites synergistically deliver excellent benzyl alcohol oxidation reaction activity with a high current density of 1500 mA·cm^(−2)at a low potential of 1.49 V(vs.reversible hydrogen electrode(RHE))and remarkable long-term durability without obvious attenuation after 530 h operation.In-situ Fourier-transform infrared spectroscopy,isotopic tracing experiment,and detailed theoretical calculations further reveal the tandem mechanism,in which the in-situ generated O^(*)species on the Fe site through OER process serve as key intermediates that bridge the subsequent electrochemical benzyl alcohol oxidation on neighboring Pt site.This coupled oxidation mechanism turns competitive OER process into mutual benefits and provides insights to achieve directional transformation of chemical bonds via construction of collaborative dual atomic sites.展开更多
Photocatalytic H_(2) production has been regarded as a charming strategy for harvesting solar energy to chemical energy yet remains a great challenge due to the weak light absorption in visible range,low charge transf...Photocatalytic H_(2) production has been regarded as a charming strategy for harvesting solar energy to chemical energy yet remains a great challenge due to the weak light absorption in visible range,low charge transfer,and fast recombination of photogenerated carriers.Here,we integrate solar-driven water splitting with benzyl alcohol(BA)oxidation,a typical platform chemical from biomass,for producing H_(2) and benzaldehyde(BAD)over ZnIn_(2)S_(4) nanosheets doped with Ni and N(Ni-N/ZIS).Mechanism studies show that Ni-N/ZIS provides a fast charge channel(i.e.,Ni-N)for separating photogenerated electrons and holes,as a result of significantly enhanced photocatalytic performance.Impressively,Ni-N/ZIS displays a H_(2) productivity of 18.7 mmol g^(-1) h^(-1) with an apparent quantum yield(AQE)of 29.1% at 420 nm,which is 37.4,10.6 and 2.8 times higher than that of pristine ZIS,N/ZIS and Ni/ZIS,surpassing all the reported noble metal-free catalysts.Besides,the productivity of BAD reaches 17.5 mmol g^(-1) h^(-1) under the irradiation of visible light(λ≥420 nm).This work integrates two significant processes(i.e.,solar-driven water splitting with benzyl alcohol oxidation)for producing H_(2) and BAD,respectively,which will contribute to alleviating the current energy and environmental crisis.展开更多
基金support from the Natural Science Foundation of China (No. 21072176)the Zhejiang ProvinceNatural Science Foundation of China (No. Y4100231)
文摘An effective and environmentally benign benzylic oxidation for transition of alkylarenes into the corresponding carbonyl compounds was reported. Alkylarenes were mixed and stirred with potassium bromide, m-chloroperbenzoic acid and a catalytic amount of iodobenzene in water at 60 ℃ for several hours, a series of the corresponding carbonyl compounds was obtained in moderate to good yields. In the reaction, iodobenzene was first oxidized by m-chloroperbenzoic acid into the hypervalent iodine intermediate which then reacted with potassium bromide to form the key radical initiator for the benzylic oxidation.
基金The Damghan University Research Council for the partial support of this work
文摘A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly（1,4-phenylene-2,5-pyridine dicarboxyamide）. This polymeric reagent was used for the selective oxidation of primary benzylic alcohols to the corresponding benzaldehydes in CH_3CN at reflux conditions.Excellent selectivity was observed between primary benzyl alcohols and secondary ones as well as non-benzylic alcohols in the oxidation reactions.Allylic alcohols were also converted to the corresponding aldehydes with good yields.
文摘Although bimetallic phosphide cocatalysts have attracted considerable interest in photocatalysis research owing to their advantageous thermodynamic characteristics,superstable and efficient cocatalysts have rarely been produced through the modulation of their structure and composition.In this study,a series of bimetallic nickel-iron phosphide(Ni_(x)Fe_(2-x)P,where 0<x<2)cocatalysts with controllable structures and overpotentials were designed by adjusting the atomic ratio of Ni/Fe onto nonmetallic elemental red phosphorus(RP)for the photocatalytic selective oxidation of benzyl alcohol(BA)coupled with hydrogen production.The catalysts exhibited an outstanding photocatalytic activity for benzaldehyde and a high H_(2)yield.The RP regulated by bimetallic phosphide cocatalysts(Ni_(x)Fe_(2-x)P)demonstrated higher photocatalytic oxidation-reduction activity than that regulated by monometallic phosphide cocatalysts(Ni_(2)P and Fe2P).In particular,the RP regulated by Ni_(1.25)Fe_(0.75)P exhibited the best photocatalytic performance.In addition,experimental and theoretical calculations further illustrated that Ni_(1.25)Fe_(0.75)P,with the optimized electronic structure,possessed good electrical conductivity and provided strong adsorption and abundant active sites,thereby accelerating electron migration and lowering the reaction energy barrier of RP.This finding offers valuable insights into the rational design of highly effective cocatalysts aimed at optimizing the photocatalytic activity of composite photocatalysts.
基金the National Natural Sci-ence Foundation of China(Nos.22271038,22378038,22172012)C.P.thanks Dalian Science and Technology Innovation Fund(No.2024JJ12CG033)+1 种基金C.P.and Z.S thank State Key Laboratory of Heavy Oil Processing(Nos.WX20230149,SKLHOP202402005)Y.-Y.L.thanks the Guangxi Key Laboratory of Information Materials,Guilin University of Electronic Technology(No.231019-K).
文摘The development of efficient photocatalysts for selective organic transformations under visible light remains a major challenge in sustainable chemistry.In this study,we present a straightforward solvothermal strategy for fabricating a defect-engineered ZrO_(2)/UiO-66-NH_(2)hybrid material with abundant oxygen vacancies,enabling the visible-light-driven oxidation of benzyl alcohol to benzaldehyde.By optimizing the solvothermal treatment duration,the composite(UiO-66-NH_(2)-2h)achieves a 74.1%conversion of benzyl alcohol with>99%selectivity toward benzaldehyde under mild conditions,substantially out-performing pristine UiO-66-NH_(2).Structural and mechanistic studies reveal that the solvothermal process induces the in situ formation of ultrasmall,uniformly dispersed ZrO_(2)nanoparticles(~2.3 nm)within the MOF matrix,while simultaneously generating abundant oxygen vacancies,as confirmed by XPS,EPR,and HRTEM analyses.The defect-mediated electronic structure of the ZrO_(2)/UiO-66-NH_(2)hybrid enhances visible-light absorption,facilitates charge carrier separation,and pro-motes efficient activation of O_(2)into superoxide radicals(·O_(2)^(−)),the primary reactive species.Transient photocurrent measure-ments and electrochemical impedance spectroscopy further verify the improved charge separation efficiency.The synergistic interplay between oxygen vacancies and the intimate ZrO_(2)/UiO-66-NH_(2)interface provides a unique defect-mediated charge transfer pathway,distinguishing this system from conventional heterojunctions.This study demonstrates a facile,one-step approach to integrate defect engineering with interfacial hybridization in MOF-based photocatalysts,off ering a scalable route for solar-driven organic synthesis.
文摘Various manganese oxide nanorods with similar one-dimensional morphology were prepared by calcination of MnOOH nanorods under different gas atmosphere and at different temper- atures, which were synthesized by a hydrothermal route. The morphology and structure of MnOx catalysts were characterized by a series of techniques including X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and tempera- ture programmed reduction （TPR）. The catalytic activities of the prepared MnO~ nanorods were tested in the liquid phase aerobic oxidation of benzyl alcohol, which follow a sequence as MnO2〉Mn203~Mn304〉MnOOH with benzaldehyde being the main product. On the basis of H2-TPR results, the superior activity of MnO2 is ascribed to its lower reduction temperature and therefore high oxygen mobility and excellent redox ability. Moreover, a good recycling ability was observed over MnO2 catalysts by simply thermal treatment in air.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.51872035 and 22078052)the Innovation Program of Dalian City of Liaoning Province(No.2019RJ03)。
文摘The water promotion effects,where water can provide a solution-mediated reaction pathway in various heterogeneous chemical catalysis,have been presented and attracted wide attention recently,yet,the rational design of catalysts with a certain ability of enhancing water-induced reaction process is full of challenges and difficulties.Here,we show that by incorporating alkali(Na,K)cations as an electronic and/or structural promoter into Pd/rGO-ZnCr_(2)O_(4)(r GO,reduced graphene oxide),the obtained Pd(Na)/rGO-ZnCr_(2)O_(4)as a representative example demonstrates an outstanding benzyl alcohol oxidation activity in the Pickering emulsion system in comparison to the alkali-free counterpart.The response experiments of water injection confirm the enhanced activity,and the Na-modified catalyst can further enhance the promotion effects of water on the reaction.The effects of alkali cations for Pd nanoparticles are identified and deciphered by a series of experimental characterizations(XPS,in situ CO-DRIFTS,and CO-TPR coupled with MS),showing that there is abundant-OH on the surface of the catalyst,which is stabilized by the formation of Pd-OH_(x).The alkali-stabilized Pd-OH_(x)is helpful to enhance the waterinduced reaction process.According to the results of in situ Raman as well as UV-vis absorption spectra,the Na-modulated Pd(Na)/rGO-ZnCr_(2)O_(4)enables the beneficial characteristics for distorting the benzyl alcohol structure and enhancing the adsorption of benzyl alcohol.Further,the mechanism for enhanced water promotion effects is rationally proposed.The strategy of alkali cations-modified catalysts can provide a new direction to effectively enhance the chemical reaction involving small molecule water.
基金financial supports from National Natural Science Foundation of China(21525316,21673254)Ministry of Science and Technology of China(2017YFA0403003)+1 种基金Chinese Academy of Sciences(QYZDYSSW-SLH013)Beijing Municipal Science&Technology Commission(Z191100007219009).
文摘Ferric acetylacetonate/covalent organic framework(Fe(acac)_(3)/COF)composite was synthesized by interfacial polymerization method at room temperature.The crystal structure,morphology and porosity property of the composite were characterized by X-ray diffraction,scanning electron microscope,transmission electron microscope and nitrogen adsorption.The interaction between Fe(acac)_(3) and COF was investigated by Fourier transform infrared spectra and X-ray photoelectron spectroscopy.The Fe(acac)_(3)/COF composite was used as a photocatalyst for the oxidation of benzyl alcohol under mild conditions.It exhibits high activity and selectivity for the reaction,of which the mechanism was investigated by determining its photoelectric properties.The Fe(acac)_(3)/COF catalyst developed in this work has application potential in other photocatalytic reactions.
基金This work was supported by the Natural Science Foundation of Anhui Province （No.11040606M39） and the Fundamental Research Funds for the Central Universities.
文摘Various Au/GO catalysts were prepared by depositing Au nanoparticles on thermally- and chemically-treated graphite oxide （GO） supports using a sol-immobilization method. The surface chemistry and structure of GO supports were characterized by a series of analytical techniques including X-ray photoelectron spectroscopy, temperature-programmed desorption and Raman spectroscopy. The results show that thermal and chemical treatments have large influence on the presence of surface oxygenated groups and the crystalline structure of GO supports. A strong support effect was observed on the catalytic activity of Au/GO catalysts in the liquid phase aerobic oxidation of benzyl alcohol. Compared to the amount and the type of surface oxygen functional groups, the ordered structure of GO supports may play a more important role in determining the catalytic performance of Au/GO catalysts.
基金supported by National Key R&D Program of China (Nos.2017YFA0207301,2017YFA0207302)the National Natural Science Foundation of China (NSFC,Nos.21725102,21601173, U1832156,21881240040,21573212)+3 种基金CAS Key Research Program of Frontier Sciences (No.QYZDB-SSW-SLH018)CAS Interdisciplinary Innovation Team,and Chinese Universities Scientific Fund (No. WK2310000067)funded by Chinese Academy of Sciences President’s International Fellowship Initiative (No. 2019PC0114)support from USTC Center for Microand Nanoscale Research and Fabrication
文摘Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions.Herein,aza-fused7 r-conjugated microporous polymer(aza-CMP)with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation.The AuPd nanoparticles anchored on aza-CMP(aza-CM P/Au_xPdy)exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm^2 light irradiation.The improved catalytic performance by the aza-CMP/Au_xPdy is attributed to the unique photothermal effect induced by aza-CMP,which can promote the catalytic benzyl alcohol oxidation occurring at Au Pd.This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect.
基金supported by the National Natural Science Foundation of China (Nos. 21272281 and 20977115)Natural Science Foundation of Hubei Province (2014CFB919)+1 种基金"the Fundamental Research Funds for the Central Universities", South-Central University for Nationalities (CZY14003)the Science and Technology Plan Innovation Team of Wuhan City (2015070504020220)
文摘A novel magnetically recoverable thioporphyrazine catalyst（CoPz（S-Bu）8/SiO2@Fe3O4） was prepared by immobilization of the cobalt octkis（butylthio） porphyrazine complex（CoPz（S-Bu）8） on silica-coated magnetic nanospheres（SiO2@Fe3O4）. The composite CoPz（S-Bu）8/SiO2@Fe3O4appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide（H2O2） as oxidant under Xe-lamp irradiation,with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number（TON） of 61.7 at ambient temperature. The biomimetic catalyst CoPz（S-Bu）8was supported on the magnetic carrier SiO2@Fe3O4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz（S-Bu）8can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications.
基金the financial support provided by the Ministry of Higher Education(MOHE)Malaysia under the Fundamental Research Grant Scheme(FRGS)(Ref no:FRGS/1/2020/TK0/XMU/02/1)The authors would like to thank the Ministry of Science,Technology and Innovation(MOSTI)Malaysia under the Strategic Research Fund(SRF-APP NanoMalaysia BICEP Project 4,S.22015)+5 种基金The authors gratefully acknowledge Agilent Technologies Malaysia Sdn.Bhd.for their contribution through chromatography.This research was supported by the National Natural Science Foundation of China(Ref no:22202168)Guangdong Basic and Applied Basic Research Foundation(Ref no:2021A1515111019)We would also like to acknowledge the financial support from the State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University(Ref.no:2023X11)The authors are thankful to the Embassy of the People's Republic of China in Malaysia for the financial support(Grant no:EENG/0045)This work was also funded by Xiamen University Malaysia Investigatorship Grant(Grant no:IENG/0038)Xiamen University Malaysia Research Fund(ICOE/0001 and XMUMRF/2021-C8/IENG/0041).
文摘Homojunction engineering is a promising modification strategy to improve charge carrier separation and photocatalytic performance of carbon nitrides.Leveraging intrinsic heptazine/triazine phase and face-to-face contact,crystalline C_(3)N_(5)(CC3N5)was combined with protonated g-C_(3)N_(4)(pgCN)through electrostatic self-assembly to achieve robust 2D/2D homojunction interfaces.The highest photocatalytic performance was obtained through crystallinity and homojunction engineering,by controlling the pgCN:CC3N5 ratio.The 25:100 pgCN:CC3N5 homo-junction(25CgCN)had the highest hydrogen production(1409.51 μmol h^(-1))and apparent quantum efficiency(25.04%,420 nm),8-fold and 180-fold higher than CC3N5 and pgCN,respectively.This photocatalytic homojunction improves benzaldehyde and hydrogen production activity,retaining 89%performance after 3 cycles(12 h)on a 3D-printed substrate.Electron paramagnetic resonance demonstrated higher·OH,·O_(2) and hole production of irradiated 25CgCN,attributed to crystallinity and homojunction interaction.Thus,electrostatic self-assembly to couple CC3N5 and pgCN in a 2D/2D homojunction interface ameliorates the performance of multifunctional solar-driven applications.
基金support provided by the Ministry of Higher Education Malaysia under the Xiamen University Malaysia.-Fundamental Research Grant Scheme(FRGS)(Ref no.FRGS/1/2024/TK08/XMU/02/1)supported by the PETRONAS-Academia Collaboration Dialogue(PACD 2023)grant,provided by PETRONAS Research Sdn.Bhd.(PRSB)+6 种基金the Ministry of Science,Technology and Innovation(MOSTI)Malaysia under the Strategic Research Fund(SRF)(S.22015)supported by the National Natural Science Foundation of China(Ref no:22202168)Guangdong Basic and Applied Basic Research Foundation(Ref no:2021A1515111019)the financial support from the State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University(Ref no:2023X11)supported by the Xiamen University,Embassy of the People's Republic of China in Malaysia(EENG/0045)funded by Xiamen University Malaysia Investigatorship Grant(Grant no:IENG/0038)Xiamen University Malaysia Research Fund(ICOE/0001,XMUMRF/2021-C8/IENG/0041 and XMUMRF/2025-C15/IENG/0080).
文摘By harnessing the power of MoS_(2) as a cocatalyst to enhance electron transfer and charge carrier separation,a groundbreaking two-in-one redox photocatalytic system was developed.This innovative system integrated 2D MoS_(2) nanosheets onto hydrangea-like Zn_(3)In_(2)S_(6) nanosheets,forming a 2D/3D heterostructure that established a stable and intimate interface.This unique architecture significantly improved cooperative photocatalytic performance,enabling the simultaneous production of hydrogen and benzaldehyde under light irradiation≥420 nm.Notably,the system achieved remarkable yields of hydrogen(41.9 mmol g^(-1) h^(-1))and benzaldehyde(38.9 mmol g^(-1) h^(-1)),surpassing the pristine Zn_(3)In_(2)S_(6) by 22.4 times.An impressive electron-hole pair utilization rate of approximately 93%was attained,underscoring the high efficiency of this two-in-one redox system.Additionally,the targeted 10 wt%-MoS_(2) loaded Zn_(3)In_(2)S_(6)(10MZ)nanohybrids at 400 nm obtained an apparent quantum yield(AQY)value of 17.66%without sacrificial agents or noble metals.The exceptional performance was attributed to improved charge carrier separation and reduced recombination,facilitated by cocatalyst integration and evidenced via photoluminescence,photoelectrochemical and Kelvin probe force microscopy measurements.This work highlighted the critical role of two-in-one redox-functioning heterojunctions in optimizing electron-hole pair utilization,offering a promising approach for sustainable energy production and organic synthesis.By demonstrating the potential for efficient,simultaneous generation of valuable chemicals and fuels,this research paves the way for the development of next-generation photocatalytic systems.
基金support provided by the Ministry of Higher Education Malaysia under the Fundamental Research Grant Scheme(FRGS)(No.FRGS/1/2024/TK08/XMU/02/1)supported by the PETRONAS-Academia Collaboration Dialogue(PACD 2023)grant,provided by PETRONAS Research Sdn.Bhd.(PRSB)+6 种基金the Ministry of Science,Technology and Innovation(MOSTI)Malaysia under the Strategic Research Fund(SRF)(S.22015)supported by the National Natural Science Foundation of China(No.22202168)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515111019)support from the State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University(No.2023X11)supported by the Embassy of the People's Republic of China in Malaysia(EENG/0045)funded by Xiamen University Malaysia Investigatorship Grant(No.IENG/0038)Xiamen University Malaysia Research Fund(ICOE/0001,XMUMRF/2021-C8/IENG/0041 and XMUMRF/2025-C15/IENG/0080).
文摘Despite advances in photocatalytic half-reduction reactions,challenges remain in effectively utilizing electron-hole pairs in concurrent redox processes.The present study involved the construction of a p-n junction Co_(3)O_(4)/Zn_(3)In_(2)S_(6)(CoZ)hybrid with a complementary band edge potential.The photocatalyst formed by the 2D assembled-nanostructure portrayed an optimal yield of 13.8(H_(2))and 13.1(benzaldehyde)mmol g^(-1)h^(-1)when exposed to light(λ>420 nm),surpassing 1%Pt-added ZIS(12.4(H_(2))and 10.71(benzaldehyde)mmol g^(-1)h^(-1)).Around 95%of the electron-hole utilization rate was achieved.The solar-to-hydrogen(STH)and apparent quantum yield(AQY)values of 0.466%and 4.96%(420nm)achieved by this system in the absence of sacrificial agents exceeded those of previous works.The exceptional performance was mostly ascribed to the synergistic development of adjoining p-n heterojunctions and the built-in electric field for effective charge separation.Moreover,scavenger studies elucidated the intricate mechanistic enigma of the dual-redox process,in which benzaldehyde was produced via O-H activation and subsequent C-H cleavage of benzyl alcohol over CoZ hybrids.Furthermore,the widespread use of the optimal 1-CoZ composites was confirmed in multiple photoredox systems.This work presents an innovative perspective on the construction of dual-functioning p-n heterojunctions for practical photoredox applications.
基金National Natural Science Foundation of China(Nos.22067009 and 22377044)for fundingNational Natural Science Foundation of China(No.21772013)Beijing Natural Science Foundation(No.2202049)for their support.
文摘We have developed a chemo-and site-selective aerobic oxidation of methylbenzenes to aromatic aldehydes.It offers several advantages,including the use of an environmentally friendly catalyst(5 mol%of inexpensive ferric chloride hexahydrate),the utilization of air as a green oxidant,mild conditions,scalability(up to 5 g scale),and operational simplicity.Furthermore,the reaction demonstrates remarkable chemo-selectivity and site-selectivity.This is evident from the lack of over-oxidation leading to carboxylic acids.Additionally,the reaction effectively converts substrates with multiple methyl groups into mono-aromatic aldehydes.The synthetic potential of this approach lies in the ability to modify complex molecules at a late stage,and conversion of inexpensive compounds into high-value fine chemicals.We expect that these characteristics will facilitate the widespread adoption of this reaction in future applications.
基金financial support from the National Natural Science Foundation of China(21722104,21671032 and 21501072)the Natural Science Foundation of Tianjin City of China(18JCJQJC47700 and 17JCQNJC05100)。
文摘Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and conversion.Herein,a facile strategy was explored for preparing a hierarchical porous heterostructure of Fe_(4)Ni_(5)S_(8)@ZnIn_(2)S_(4)(FNS@ZIS)by the in situ growth of ZIS nanosheets on Prussian blue analogue(PBA)-derived bimetallic FNS sulfides.A series of FNS@ZIS hierarchical structures were facilely prepared by adjusting the loading amount(n%)of FNS(n=19,26,and 32 for FNS@ZIS-1-3).These structures can efficiently drive the solar co-production of H_(2) and organic chemicals.The optimal co-production was achieved with FNS@ZIS-2,affording a H_(2) evolution rate of 10465μmol·g^(-1)·h^(-1),along with high selectivity for the oxidation of benzyl alcohol to benzaldehyde(>99.9%).The performance was 22 and 31 times higher than that of FNS and ZIS,respectively,and even superior to the state-of-the-art results achieved using various sacrificial agents.Further mechanistic study indicated that the unique hierarchical core/shell architecture can facilitate interfacial charge separation,afford bimetallic synergy,abundant active sites and excellent photostability.This work highlights a simple and efficient method for preparing porous multimetallic hierarchical structures for the solar co-production of organic chemicals and H_(2) fuel.
基金supported by the National Basic Research Program of China(2013CB933104)the National Natural Science Foundation of China(21525313,21173204,21373192,U1332113)+1 种基金MOE Fundamental Research Funds for the Central Universities(WK2060030017)Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
文摘Simultaneous generation of H_(2) fuel and value-added chemicals has attracted increasing attention since the photogenerated electrons and holes can be both employed to convert solar light into chemical energy.Herein,for realizing UV-visible-NIR light driven dehydrogenation of benzyl alcohol(BA)into benzaldehydes(BAD)and H_(2),a novel localized surface plasmon resonance(LSPR)enhanced S-scheme heterojunction was designed by combining noble-metal-free plasmon MoO_(3-x) as oxidation semiconductor and Zn_(0.1)Cd_(0.9)S as reduction semiconductor.The photoredox system of Zn_(0.1)Cd_(0.9)S/MoO_(3-x) displayed an unconventional reaction model,in which the BA served as both electron donor and acceptor.The S-scheme charge transfer mechanism induced by the formed internal electric field enhanced the redox ability of charge carriers thermodynamically and boosted charge separation kinetically.Moreover,due to the LSPR effect of MoO_(3-x) nanosheets,Zn_(0.1)Cd_(0.9)S/MoO_(3-x) photocatalysts exhibited strong absorption in the region of full solar spectrum.Therefore,the Zn_(0.1)Cd_(0.9)S/MoO_(3-x) composite generated H_(2) and BAD simultaneously via selective oxidation of BA with high production(34.38 and 33.83 mmol×g^(–1) for H_(2) and BAD,respectively)upon full solar illumination.Even under NIR light irradiation,the H_(2) production rate could up to 94.5 mmol×g^(–1)×h^(–1).In addition,the Zn_(0.1)Cd_(0.9)S/MoO_(3-x) composite displayed effective photocatalytic H_(2) evolution rate up to 149.2 mmol×g^(–1)×h^(–1) from water,which was approximate 6 times that of pure Zn_(0.1)Cd_(0.9)S.This work provides a reference for rational design of plasmonic S-scheme heterojunction photocatalysts for coproduction of high-value chemicals and solar fuel production.
文摘Tertiary phosphines and their oxides react with oxalyl bromide to generate corresponding quaternary phosphonium salts,which can be further transformed as active intermediates to facilitate the bromination of alcohols and the dibromination of unsaturated hydrocarbons.This chemical process carries substantial research significance in the field of organic synthesis.In this study,two types of triaryl phosphine oxides and benzyl diaryl phosphine oxides containing alkyne groups were designed and synthesized.These compounds were then subjected to reaction with oxalyl bromide,resulting in the formation of novel benzophosphonium tribromides and trans-phosphoryl dibromoalkenes,respectively.These findings demonstrate variations from their reactions with oxalyl chloride.Furthermore,the benzophosphonium tribromide obtained can act as an alternative reagent for bromine,enabling the direct bromination of aromatics compounds,olefin,alkyne and acetophenone derivatives.
基金supported by the National Natural Science Foundation of China(Nos.22375131,52172096,and 22405180).
文摘Active oxygen radicals(OH^(*)/O^(*)/OOH^(*))generated from oxygen evolution reaction(OER)play a crucial role in facilitating the electrooxidation of organic compounds into high value-added chemicals.However,constructing atomically precise active sites with a specific function to catalyze water-coupled electrooxidation reactions in a tandem system still confronts a great challenge.Herein,we propose a novel water-participating benzyl alcohol electrooxidation tandem process by constructing homogeneous isolated Fe-Pt dual-atom site catalysts on CoOOH nanosheet arrays(FePt DAC).The Fe and Pt dual atomic sites synergistically deliver excellent benzyl alcohol oxidation reaction activity with a high current density of 1500 mA·cm^(−2)at a low potential of 1.49 V(vs.reversible hydrogen electrode(RHE))and remarkable long-term durability without obvious attenuation after 530 h operation.In-situ Fourier-transform infrared spectroscopy,isotopic tracing experiment,and detailed theoretical calculations further reveal the tandem mechanism,in which the in-situ generated O^(*)species on the Fe site through OER process serve as key intermediates that bridge the subsequent electrochemical benzyl alcohol oxidation on neighboring Pt site.This coupled oxidation mechanism turns competitive OER process into mutual benefits and provides insights to achieve directional transformation of chemical bonds via construction of collaborative dual atomic sites.
基金supported by the National Key R&D Program of China(2022YFA1504500)National Natural Science Foundation of China(52472310,22025108,U21A20327,and 22121001)+4 种基金Gusu Leading Talent Program(ZXL2024347)Guangdong Provincial Natural Science Fund for Distinguished Young Scholars(2021B1515020081)Pioneer Hundred Talents Program of Chinese Academy of SciencesNatural Science Foundation of the Jiangsu Higher Education Institutions(22KJA430009)Science and Technology Development Plan of Suzhou(ZXL2022176).
文摘Photocatalytic H_(2) production has been regarded as a charming strategy for harvesting solar energy to chemical energy yet remains a great challenge due to the weak light absorption in visible range,low charge transfer,and fast recombination of photogenerated carriers.Here,we integrate solar-driven water splitting with benzyl alcohol(BA)oxidation,a typical platform chemical from biomass,for producing H_(2) and benzaldehyde(BAD)over ZnIn_(2)S_(4) nanosheets doped with Ni and N(Ni-N/ZIS).Mechanism studies show that Ni-N/ZIS provides a fast charge channel(i.e.,Ni-N)for separating photogenerated electrons and holes,as a result of significantly enhanced photocatalytic performance.Impressively,Ni-N/ZIS displays a H_(2) productivity of 18.7 mmol g^(-1) h^(-1) with an apparent quantum yield(AQE)of 29.1% at 420 nm,which is 37.4,10.6 and 2.8 times higher than that of pristine ZIS,N/ZIS and Ni/ZIS,surpassing all the reported noble metal-free catalysts.Besides,the productivity of BAD reaches 17.5 mmol g^(-1) h^(-1) under the irradiation of visible light(λ≥420 nm).This work integrates two significant processes(i.e.,solar-driven water splitting with benzyl alcohol oxidation)for producing H_(2) and BAD,respectively,which will contribute to alleviating the current energy and environmental crisis.
