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Carbon Doping Triggered Efficient Electrochemical Hydrogen Evolution of Cross-Linked Porous Ru-MoO_(2) Via Solid-Phase Reaction Strategy 被引量:1
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作者 Jialin Cai Jianye Yang +7 位作者 Xin Xie Jie Ding Leyan Liu Wanyu Tian Yushan Liu Zhiyong Tang Baozhong Liu Siyu Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期392-400,共9页
The defect-free structure of Mo-based materials is a“double-edged sword”,which endows the material with excellent stability,but limits its chemical versatility and application in electrochemical hydrogen evolution r... The defect-free structure of Mo-based materials is a“double-edged sword”,which endows the material with excellent stability,but limits its chemical versatility and application in electrochemical hydrogen evolution reaction(HER).Carbon doping engineering is an attractive strategy to effectively improve the performance of Mo-based catalyst and maintain their stability.Herein,we report a cross-linked porous carbon-doped MoO_(2)(C–MoO_(2))-based catalyst Ru/C–MoO_(2) for electrochemical HER,which is prepared by the convenient redox solid-phase reaction(SPR)of porous RuO_(2)/Mo_(2)C composite precursor.Theoretical studies reveal that due to the presence of carbon atoms,the electronic structure of C–MoO_(2) has been properly adjusted,and the loaded small Ru nanoparticles provide a fast water dissociation rate and moderate H adsorption strength.In electrochemical studies under a pH-universal environment,Ru/C–MoO_(2) electrocatalyst exhibits a low overpotential at a current density of 10 mA cm^(-2) and has a low Tafel slope.Meanwhile,Ru/C-MoO_(2) has excellent stability for more than 100 h at an initial current density of 100 mA cm^(-2). 展开更多
关键词 carbon doped hydrogen evolution reaction macro-meso-micropore MoO_(2) RU solid-phase reaction
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Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery 被引量:1
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作者 Leijun Ye Weiheng Chen +1 位作者 Zhong-Jie Jiang Zhongqing Jiang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第7期14-25,共12页
Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well... Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma treatment.As a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V vs.reversible hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported electrocatalysts.Impressively,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling stability.First-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics rates.This work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs. 展开更多
关键词 HETEROJUNCTION oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes
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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation
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作者 Yonghai Feng Min Yu +2 位作者 Minjia Meng Lei Liu Dewei Rao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期27-35,共9页
In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited... In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C cleavage.Given the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to LA.The carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction efficacy.Therefore,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→LA.Specifically,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling. 展开更多
关键词 Selective oxidation Copper and nitrogen doped carbon 1 2-PROPANEDIOL Ultrasmall Cu nanoparticles Lactic acid
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Structure,electronic,and nonlinear optical properties of superalkaline M_(3)O(M=Li,Na)doped cyclo[18]carbon
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作者 刘晓东 卢其亮 罗其全 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期311-317,共7页
Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an ef... Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer occurs.In this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not coplanar.The C_(18) ring still exhibits alternating long and short bonds.The charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm. 展开更多
关键词 superalkaline doped carbon structure and electronic properties nonlinear optical properties density functional theory(DFT)
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New strategy of S,N co‐doping of conductive‐copolymer‐derived carbon nanotubes to effectively improve the dispersion of PtCu nanocrystals for boosting the electrocatalytic oxidation of methanol 被引量:2
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作者 Jingping Zhong Kexin Huang +6 位作者 Wentao Xu Huaguo Tang Muhammad Waqas Youjun Fan Ruixiang Wang Wei Chen Yixuan Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1205-1215,共11页
Efficacious regulation of the geometric and electronic structures of carbon nanomaterials via the introduction of defects and their synergy is essential to achieving good electrochemical performance.However,the guidel... Efficacious regulation of the geometric and electronic structures of carbon nanomaterials via the introduction of defects and their synergy is essential to achieving good electrochemical performance.However,the guidelines for designing hybrid materials with advantageous structures and the fundamental understanding of their electrocatalytic mechanisms remain unclear.Herein,superfine Pt and PtCu nanoparticles supported by novel S,N‐co‐doped multi‐walled CNT(MWCNTs)were prepared through the innovative pyrolysis of a poly(3,4‐ethylenedioxythiophene)/polyaniline copolymer as a source of S and N.The uniform wrapping of the copolymer around the MWCNTs provides a high density of evenly distributed defects on the surface after the pyrolysis treatment,facilitating the uniform distribution of ultrafine Pt and PtCu nanoparticles.Remarkably,the Pt_(1)Cu_(2)/SN‐MWCNTs show an obviously larger electroactive surface area and higher mass activity,stability,and CO poisoning resistance in methanol oxidation compared to Pt/SN‐MWCNTs,Pt/S‐MWCNTs,Pt/N‐MWCNTs,and commercial Pt/C.Density functional theory studies confirm that the co‐doping of S and N considerably deforms the CNTs and polarizes the adjacent C atoms.Consequently,both the adsorption of Pt1Cu2 onto the SN‐MWCNTs and the subsequent adsorption of methanol are enhanced;in addition,the catalytic activity of Pt_(1)Cu_(2)/SN‐MWCNTs for methanol oxidation is thermodynamically and kinetically more favorable than that of its CNT and N‐CNT counterparts.This work provides a novel method to fabricate high‐performance fuel cell electrocatalysts with highly dispersed and stable Pt‐based nanoparticles on a carbon substrate. 展开更多
关键词 Methanol oxidation Conductive copolymers Dual‐doped carbon nanotubes Pt‐based nanoparticles DFT calculation
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Mechanochemical Synthesis of Visible-light Induced Photocatalyst with Nitrogen and Carbon Doping 被引量:2
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作者 殷澍 Maskazu Komatsu +4 位作者 张其武 李锐星 唐清 Fumio Saito Tsugio Sato 《过程工程学报》 CAS CSCD 北大核心 2006年第3期477-481,共5页
Nitrogen and/or carbon doped titania photocatalysts were prepared by a novel mechanochemical method. The prepared powders possessed two absorption edges around 400 and 540 nm wavelengths and showed excellent photocata... Nitrogen and/or carbon doped titania photocatalysts were prepared by a novel mechanochemical method. The prepared powders possessed two absorption edges around 400 and 540 nm wavelengths and showed excellent photocatalytic ability for nitrogen monoxide oxidation under visible light irradiation. Under the irradiation of visible light of wavelength >510 nm,37% of nitrogen monoxide could be continuously removed by the carbon and nitrogen co-doped titania prepared by planetary ball milling of P-25 titania–10% hexamethylenetetramine mixture followed by calcination in air at 400-C. 展开更多
关键词 mechanochemical synthesis titania photocatalyst carbon and nitrogen doping nitrogen monoxide OXIDATION
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Synergistic effects of carbon doping and coating of TiO_(2) with exceptional photocurrent enhancement for high performance H2 production from water splitting 被引量:2
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作者 Yingying Wang Yan-Xin Chen +7 位作者 Tarek Barakat Tian-Ming Wang Alain Krief Yu-Jia Zeng Marvin Laboureur Luca Fusaro Hong-Gang Liao Bao-Lian Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期141-151,共11页
The"one pot"simultaneous carbon coating and doping of TiO_(2) materials by the hydrolysis of TiCl4 in fructose is reported.The synergistic effect of carbon doping and coating of TiO_(2) to significantly boos... The"one pot"simultaneous carbon coating and doping of TiO_(2) materials by the hydrolysis of TiCl4 in fructose is reported.The synergistic effect of carbon doping and coating of TiO_(2) to significantly boost textural,optical and electronic properties and photocurrent of TiO_(2) for high performance visible light H2 production from water splitting has been comprehensively investigated.Carbon doping can significantly increase the thermal stability,thus inhibiting the phase transformation of the Titania material from anatase to rutile while carbon coating can suppress the grain aggregation of TiO_(2).The synergy of carbon doping and coating can not only ensure an enhanced narrowing effect of the electronic band gap of TiO_(2) thus extending the absorption of photocatalysts to the visible regions,but also promote dramatically the separation of electron-hole pairs.Owing to these synergistic effects,the carbon coated and doped TiO_(2) shows much superior photocatalytic activity for both degradation of organics and photocatalytic/photoelectro chemical(PEC)water splitting under simulated sunlight illumination.The photocatalytic activity of obtained materials can reach 5,4 and 2 times higher than that of pristine TiO_(2),carbon doped TiO_(2) and carbon coated TiO_(2),respectively in the degradation of organic pollutants.The carbon coated and doped TiO_(2) materials exhibited more than 37 times and hundreds of times photocurrent enhancement under simulated sunlight and visible light,respectively compared to that of pristine TiO_(2).The present work providing new comprehensive understanding on carbon coating and doping effect could be very helpful for the development of advanced TiO_(2) materials for a large series of applications. 展开更多
关键词 carbon coating and doping TiO_(2) ONE-POT PEC water splitting Solar light photocatalysis
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Influence of Sodium Carbonate Amount on Crystalline Phase and Structure Stability for Doping Nickel Hydroxide
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作者 赵腾起 朱燕娟 +3 位作者 LI Wenhua FENG Zuyong ZHANG Wei JIAN Xiuwen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第3期552-558,共7页
Alpha nickel hydroxide has better performances than commercial beta nickel hydroxide. However, the main defect is that α-phase is difficult to synthesize and easily transformed to β-phase Ni(OH)2 upon aging in a s... Alpha nickel hydroxide has better performances than commercial beta nickel hydroxide. However, the main defect is that α-phase is difficult to synthesize and easily transformed to β-phase Ni(OH)2 upon aging in a strong alkaline solution. In this study, the Al-Co, Al-Yb, Yb-Co and Al-Yb-Co multiple doping was used respectively. By controlling the amount of sodium carbonate, the α-Ni(OH)2 was prepared by ultrasonic-assisted precipitation. And the influence of sodium carbonate on the crystalline phase and structure stability for alpha nickel hydroxide was studied. The results demonstrate that, with increasing amount, the biphase nickel hydroxide transforms to pure alpha nickel hydroxide gradually, and the structure stability is also improved. When the amount of sodium carbonate is 2 g, the sample still keeps α-Ni(OH)2 after being aged for 30 days, for Al-Yb-Co-Ni(OH)2. And when the amount is less than 2 g, the phase transformations exist in the samples with different extents. These results demonstrated that the amount of sodium carbonate is a critical factor to maintain the structural stability of α-Ni(OH)2. 展开更多
关键词 sodium carbonate nickel hydroxide crystalline structural stability multiple doping
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Porous carbon materials for CO_(2)capture,storage and electrochemical conversion
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作者 Changmin Kim Siddulu Naidu Talapaneni Liming Dai 《Materials Reports(Energy)》 2023年第2期43-61,I0002,共20页
Continuous accumulation and emission into the atmosphere of anthropogenic carbon dioxide(CO_(2)),a major greenhouse gas,has been recognized as a primary contributor to climate change associated with the global warming... Continuous accumulation and emission into the atmosphere of anthropogenic carbon dioxide(CO_(2)),a major greenhouse gas,has been recognized as a primary contributor to climate change associated with the global warming and acidification of oceans.This has led to drastic changes in the natural ecosystem,and hence an unhealthy ecological environment for human society.Thus,the effective mitigation of the ever increasing CO_(2)emission has been recognized as the most important global challenge.To achieve zero carbon footprint,novel materials and approaches are required for potentially reducing the CO_(2)release,while our current fossil-fuel-based energy must be replaced by renewable energy free from emissions.In this paper,porous carbons with hierarchical pore structures are promising for CO_(2)adsorption and electrochemical CO_(2)reduction owing to their high specific surface area,excellent catalytic performance,low cost and long-term stability.Since efficient gas-phased(electro)catalysis involves the access of reactants to active sites at the gas-liquid-solid triple phase,the hierarchical porous carbon materials possess multiple advantages for various CO_(2)-related applications with enhanced volumetric and gravimetric activities(e.g.,CO_(2)uptake and current density)for practical operations.Recent studies have demonstrated that porous carbon materials exhibited notable activities as CO_(2)adsorbents and provided facile conducting pathways and mass diffusion channels for efficient electrochemical CO_(2)reduction even under the high current operation conditions.Herein,we summarize recent advances in porous carbon materials for CO_(2)capture,storage,and electrochemical conversion.Prospectives and challenges on the rational design of porous carbon materials for scalable and practical CO_(2)capture and conversion are also discussed. 展开更多
关键词 Porous carbons carbon dioxide storage carbon dioxide reduction ELECTROCATALYSTS carbon dioxide adsorbents Doped carbon
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Effect of carbon on microstructures of Ti-45Al-3Fe-2Mo-xC alloy 被引量:2
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作者 周灿旭 刘彬 +2 位作者 刘咏 邱从章 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1730-1736,共7页
The effect of carbon addition on the microstructures of TiAl-based alloy(Ti-45Al-3Fe-2Mo) was studied.The proportion of β/B2 phase reduces with the content of carbon increasing,while the colony size increases.With ... The effect of carbon addition on the microstructures of TiAl-based alloy(Ti-45Al-3Fe-2Mo) was studied.The proportion of β/B2 phase reduces with the content of carbon increasing,while the colony size increases.With increasing the carbon content,the lamellar spacing first decreases from 267 nm(Ti-45Al-3Fe-2Mo) to 237 nm(Ti-45Al-3Fe-2Mo-0.3C) and 155 nm(Ti-45Al-3Fe-2Mo-0.5C),but then increases to 230 nm(Ti-45Al-3Fe-2Mo-1.0C) with further increase in C level,which is affected by the inhibition of carbon atom and precipitation of carbides at the lamellar interface.Precipitation of carbides shows a response to aging time at 800 ℃.P-type carbides grow up at the boundaries and near the dislocation areas with the prolonging of aging time.And these carbides are projected different morphology in different beam directions(BD).The effects of these microstructural modifications were examined and the observations were discussed. 展开更多
关键词 TiAl alloy carbon doping microstructure CARBIDE
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Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction
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作者 Kyung‐Jong Noh Byoung Joon Park +5 位作者 Ying Wang Yejung Choi Sang‐Hoon You Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期79-90,共12页
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc... Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions. 展开更多
关键词 atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst
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Co_3O_4 supported on N,P-doped carbon as a bifunctional electrocatalyst for oxygen reduction and evolution reactions 被引量:6
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作者 黄颖彬 张敏 +2 位作者 柳鹏 程发良 王立世 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1249-1256,共8页
Noble metals, such as platinum, ruthenium and iridium‐group metals, are often used as oxygen reduction or evolution reaction (ORR/OER) electrocatalysts. To reduce the cost and provide an application of bifunctional... Noble metals, such as platinum, ruthenium and iridium‐group metals, are often used as oxygen reduction or evolution reaction (ORR/OER) electrocatalysts. To reduce the cost and provide an application of bifunctional catalysis, in this work, cobalt oxide supported on nitrogen and phospho‐rus co‐doped carbon (Co3O4/NPC) was fabricated and examined as a bifunctional electrocatalyst for OER and ORR. To prepare Co3O4/NPC, NPC was pyrolyzed from melamine and phytic acid support‐ed on carbon, followed by the solvothermal synthesis of Co3O4 on NPC. Linear sweep voltammetry was used to evaluate the activity for OER and ORR. For OER, Co3O4/NPC showed an onset potential of 0.54 V (versus the saturated calomel electrode) and a current density of 21.95 mA/cm2 at 0.80 V, which was better than both Co3O4/C and NPC. The high activity of Co3O4/NPC was attributed to a synergistic effect of the N, P co‐dopants and Co3O4. For ORR, Co3O4/NPC exhibited an activity close to commercial Pt/C in terms of the diffusion limited current density (–4.49 vs–4.76 mA/cm2 at–0.80 V), and Co3O4 played the key role for the catalysis. Chronoamperometry (current versus time) was used to evaluate the stability, which showed that Co3O4/NPC maintained 46%current after the chronoamperometry test for OER and 95% current for ORR. Overall, Co3O4/NPC exhibited high activity and improved stability for both OER and ORR. 展开更多
关键词 Cathode catalyst Oxygen reduction reaction Oxygen evolution reaction Doped carbon COBALT
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Nitrogen doped carbon catalyzing acetylene conversion to vinyl chloride 被引量:11
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作者 Xingyun Li Xiulian Pan Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期131-135,共5页
Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vi... Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vital to explore alternative catalysts without mercury. We report here that N-doped carbon can catalyze directly transformation of acetylene to vinyl chloride. Particularly, N-doped high surface area mesoporous carbon exhibits a rather high activity with the acetylene conversion reaching 77% and vinyl chloride selectivity above 98% at a space velocity of 1.0 mL.min-l.g-1 and 200 ~C. It delivers a stable performa℃nce within a test period of 100h and no obvious deactivation is observed, demonstrating potentials to substitute the notoriously toxic mercuric chloride catalyst. 展开更多
关键词 ACETYLENE HYDROCHLORINATION vinyl chloride MERCURY-FREE N doped carbon
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Enhanced visible-light photocatalytic oxidation capability of carbon-doped TiO_2 via coupling with fly ash 被引量:13
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作者 Ning An Yuwei Ma +3 位作者 Juming Liu Huiyan Ma Jucai Yang Qiancheng Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第12期1890-1900,共11页
A carbon‐doped TiO2/fly ash support(C‐TiO2/FAS)composite photocatalyst was successfully synthesized through sol impregnation and subsequent carbonization.The carbon dopants were derived from the organic species gene... A carbon‐doped TiO2/fly ash support(C‐TiO2/FAS)composite photocatalyst was successfully synthesized through sol impregnation and subsequent carbonization.The carbon dopants were derived from the organic species generated during the synthesis of the C‐TiO2/FAS composite.A series of analytical techniques,such as scanning electron microscopy(SEM),attenuated total reflection‐Fourier transform infrared(ATR‐FTIR)spectroscopy,X‐ray photoelectron spectroscopy(XPS),and ultraviolet‐visible diffuse reflectance spectroscopy(UV‐Vis DRS),were used to characterize the properties of the prepared samples.The results indicated that C‐TiO2 was successfully coated on the FAS surface.Coupling between C‐TiO2 and FAS resulted in the formation of Si–O–C and Al–O–Ti bonds at their interface.The formation of Si–O–C and Al–O–Ti bonds gave rise to a positive shift of the valence band edge of C‐TiO2 and enhanced its oxidation capability of photogenerated holes as well as photodegradation efficiency of methyl orange.Moreover,the C‐TiO2/FAS photocatalyst exhibited favorable reusability and separability.This work may provide a new route for tuning the electronic band structure of TiO2. 展开更多
关键词 Fly ash TiO2 carbon doping Visible‐light photocatalysis Photocatalytic oxidation
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Decomposition kinetics of carbon-doped FeCoCrNiMn high-entropy alloy at intermediate temperature 被引量:9
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作者 Jian PENG Zi-yong LI +3 位作者 Xin-bo JI Yan-le SUN Li-ming FU Ai-dang SHAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第7期1884-1894,共11页
Phase decomposition kinetics and the corresponding mechanical properties of the severe cold-rolled(SCRed) carbon-doped(1.3 at.%) equimolar FeCoCrNiMn high-entropy alloy(HEA) after being annealed at 500 ℃ were investi... Phase decomposition kinetics and the corresponding mechanical properties of the severe cold-rolled(SCRed) carbon-doped(1.3 at.%) equimolar FeCoCrNiMn high-entropy alloy(HEA) after being annealed at 500 ℃ were investigated. This single face-centered cubic(FCC) solid-solution HEA decomposed to M23 C6+L10, B2, and σ in chronological order. The formation kinetics of the L10, B2, and σ phases followed the Johnson-Mehl-AvramiKolmogorov(JMAK) equation. The yield strength of the HEA was 1520 MPa and increased to 1920 MPa after being annealed at 500 ℃ for 1 h, as a result of the formation of nanosized M23 C6 and L10. Both strength and ductility decreased after 2 d of annealing due to the increase of volume fractions and the coarsening of the M23C6 and L10 precipitates. From 4 to 32 d, the hardness was found to increase, which is ascribed to the rapid formation of the B2 and σ phases. From 32 to 64 d, the hardness increased further to finally reach about HV 760, with the FCC matrix almost exhausted to form the M23 C6, L10, B2, and σ phases. The results of this work may serve as a guide for the heat-treatment of carbon-doped HEAs. 展开更多
关键词 FeCoCrNiMn high-entropy alloy decomposition kinetics mechanical properties carbon doping
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Biomass derived porous nitrogen doped carbon for electrochemical devices 被引量:4
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作者 Litao Yan Jiuling Yu +2 位作者 Jessica Houston Nancy Flores Hongmei Luo 《Green Energy & Environment》 SCIE 2017年第2期84-99,共16页
Biomass derived porous nanostructured nitrogen doped carbon(PNC) has been extensively investigated as the electrode material for electrochemical catalytic reactions and rechargeable batteries. Biomass with and without... Biomass derived porous nanostructured nitrogen doped carbon(PNC) has been extensively investigated as the electrode material for electrochemical catalytic reactions and rechargeable batteries. Biomass with and without containing nitrogen could be designed and optimized to prepare PNC via hydrothermal carbonization, pyrolysis, and other methods. The presence of nitrogen in carbon can provide more active sites for ion absorption, improve the electronic conductivity, increase the bonding between carbon and sulfur, and enhance the electrochemical catalytic reaction. The synthetic methods of natural biomass derived PNC, heteroatomic co-or tri-doping into biomass derived carbon and the application of biomass derived PNC in rechargeable Li/Na batteries, high energy density Li-S batteries, supercapacitors, metal-air batteries and electrochemical catalytic reaction(oxygen reduction and evolution reactions, hydrogen evolution reaction) are summarized and discussed in this review. Biomass derived PNCs deliver high performance electrochemical storage properties for rechargeable batteries/supercapacitors and superior electrochemical catalytic performance toward hydrogen evolution, oxygen reduction and evolution, as promising electrodes for electrochemical devices including battery technologies, fuel cell and electrolyzer. 展开更多
关键词 BIOMASS Nitrogen doped carbon BATTERIES Fuel cell ELECTROLYZER
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Wheat flour-derived N-doped mesoporous carbon extrudes as an efficient support for Au catalyst in acetylene hydrochlorination 被引量:4
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作者 Jie Liu Guojun Lan +2 位作者 Yiyang Qiu Xiaolong Wang Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1664-1671,共8页
We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent ... We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent catalytic performance in acetylene hydrochlorination.Herein,we examined the activity of Au supported on N‐MC(Au/N‐MC)and compared it with that of Au supported on nitrogen‐free mesoporous carbon(Au/MC).The acetylene conversion of Au/N‐MC was 50%at 180°C with an acetylene space velocity of 600 h–1 and VHCl/VC2H2 of 1.1,which was double the activity of Au/MC(25%).The introduced nitrogen atoms acted as anchor sites that stabilized the Au3+species and inhibited the reduction of Au3+to Au0 during the preparation of Au/N‐MC catalysts. 展开更多
关键词 Au catalyst Mercury free catalyst Acetylene hydrochlorination N doped mesoporous carbon
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Graphitic‐shell encapsulated FeNi alloy/nitride nanocrystals on biomass‐derived N‐doped carbon as an efficient electrocatalyst for rechargeable Zn‐air battery 被引量:12
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作者 Mingjie Wu Gaixia Zhang +5 位作者 Yongfeng Hu Jian Wang Tianxiao Sun Tom Regier Jinli Qiao Shuhui Sun 《Carbon Energy》 CAS 2021年第1期176-187,共12页
Oxygen reduction/evolution reactions(ORR/OERs)catalysts play a key role in the metal‐air battery and water‐splitting process.Herein,we developed a facile template‐free method to fabricate a new type of non–noble m... Oxygen reduction/evolution reactions(ORR/OERs)catalysts play a key role in the metal‐air battery and water‐splitting process.Herein,we developed a facile template‐free method to fabricate a new type of non–noble metal‐based hybrid catalyst which consists of binary FeNi alloy/nitride nanocrystals with graphitic‐shell and biomass‐derived N‐doped carbon(NC)(FexNiyN@C/NC).This novel nanostructure exhibits superior performance for ORR/OER,which can be attributed to the strong interactions between the graphitic‐shell encapsulated FeNi alloy/nitride nanocrystals and the N‐doped porous carbon substrate.The X‐ray absorption spectroscopy technique was employed to reveal the underlying mechanisms for the excellent performance.The assembled Zn‐air battery device exhibits outstanding charging/discharging performance and cycling stability,indicating the great potential of this type of novel catalysts. 展开更多
关键词 binary FeNi alloy/nitride N‐doped carbon oxygen reduction and evolution reactions X‐ray absorption spectroscopy Zn‐air battery
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Carbon‐based materials for all‐solid‐state zinc–air batteries 被引量:8
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作者 Dan Yang Dong Chen +4 位作者 Yu Jiang Edison Huixiang Ang Yuezhan Feng Xianhong Rui Yan Yu 《Carbon Energy》 CAS 2021年第1期50-65,共16页
Solid‐state Zn–air batteries(ZABs)hold great potential for application in wearable and flexible electronics.However,further commercialization of current ZABs is still limited by the poor stability and low energy eff... Solid‐state Zn–air batteries(ZABs)hold great potential for application in wearable and flexible electronics.However,further commercialization of current ZABs is still limited by the poor stability and low energy efficiency.It is,thus,crucial to develop efficient catalysts as well as optimize the solid electrolyte system to unveil potential of the ZAB technology.Due to the low cost and versatility in tailoring the structures and properties,carbon materials have been extensively used as the conductive substrates,catalytic air electrodes,and important components in the electrolytes for the solid‐state ZABs.Within this context,we discuss the challenges facing current solid‐state ZABs and summarize the strategies developed to modify properties of carbon‐based electrodes and electrolytes.We highlight the metal−organic framework/covalent organic framework‐based electrodes,heteroatom‐doped carbon,and the composites formed of carbon with metal oxides/sulfides/phosphides.We also briefly discuss the progress of graphene oxide‐based solid electrolyte. 展开更多
关键词 carbon material heteroatom‐doped carbon solid electrolyte solid‐state Zn–air battery
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Highly dispersed few-layer MoS_2 nanosheets on S, N co-doped carbon for electrocatalytic H_2 production 被引量:2
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作者 Shixin Hua Dan Qu +5 位作者 Li An Guangcheng Xi Ge Chen Fan Li Zhijun Zhou Zaicheng Sun 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第6期1028-1037,共10页
Ultrathin small MoS2nanosheets exhibit a higher electrocatalytic activity for the hydrogen evolution reaction.However,strong interactions between MoS2layers may result in aggregation;together with the low conductivity... Ultrathin small MoS2nanosheets exhibit a higher electrocatalytic activity for the hydrogen evolution reaction.However,strong interactions between MoS2layers may result in aggregation;together with the low conductivity of MoS2,this may lower its electrocatalytic activity.In this paper we present a method that we developed to directly produce solid S,N co‐doped carbon(SNC)with a graphite structure and multiple surface groups through a hydrothermal route.When Na2MoO4was added to the reaction,polymolybdate could be anchored into the carbon materials via a chemical interaction that helps polymolybdate disperse uniformly into the SNC.After a high temperature treatment,polymolybdate transformed into MoS2at800°C for6h in a N2atmosphere at a heating rate of5°C/min,owing to S2?being released from the SNC during the treatment(denoted as MoS2/SNC‐800‐6h).The SNC effectively prevents MoS2from aggregating into large particles,and we successfully prepared highly dispersed MoS2in the SNC matrix.Electrochemical characterizations indicate that MoS2/SNC‐900‐12h exhibits a low onset potential of115mV and a low overpotential of237mV at a current density of10mA/cm2.Furthermore,MoS2/SNC‐900‐12h also had an excellent stability with only^2.6%decay at a current density of10mA/cm2after5000test cycles. 展开更多
关键词 MoS2 nanosheet S N co‐doped carbon Electrocatalytic hydrogen production Composite Hydrogen evolution reaction
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