Gold nanoparticles(AuNPs)supported on the Cu-doped LaMnO_(3)perovskites exhibit strong Au-Mn-Cu synergy in the aerobic oxidation of gaseous ethanol to acetaldehyde(AC).The Au/LaMnCuO_(3)catalysts achieve AC yields exc...Gold nanoparticles(AuNPs)supported on the Cu-doped LaMnO_(3)perovskites exhibit strong Au-Mn-Cu synergy in the aerobic oxidation of gaseous ethanol to acetaldehyde(AC).The Au/LaMnCuO_(3)catalysts achieve AC yields exceeding 90%and a space-time yield of 715 g_(AC)g_(AU)^(-1)h^(-1)at 225℃,outperforming reported catalysts.The outstanding performance is attributed to adjacent Cu^(+)and Mn^(2+)ions in the perovskite surface,which,together with nearby AuNPs,contribute to the high activity and stability.The best-performing catalyst contains a Cu/Mn ratio of 1/3 in the perovskite.Doping too much Cu into the perovskite leads to metallic Cu,suppressing catalyst performance.Density functional theory(reaction energetics,electronic structure analysis)and microkinetics simulations aided in understanding the synergy between Cu and Mn and the role of AuNPs.The reaction involves two H abstraction steps:(1)O-H cleavage of adsorbed ethanol by the basic perovskite lattice oxygen atom and(2)α-C-H cleavage by AuNPs,yielding AC and adsorbed water.Molecular O_(2)adsorbs in the oxygen vacancy(O_(V))formed by water removal,generating a peroxide anion(O_(2)^(2-))as the activated oxygen species.In the second part of the catalytic cycle,the basic O_(2)^(2-)species abstracts the H atom from another ethanol molecule,followed byα-C-H cleavage by AuNPs,AC production,and water removal.Water formation in the second part of the catalytic cycle is the rate-controlling step for Au/LaMnO_(3)and Au/LaMnCuO_(3)models.Moderate Cu doping enhances the essential Cu^(+)-OV-Mn^(2+)sites and lowers the barrier for water formation due to the weaker Cu-O bond than the Mn-O bond.In contrast,excessive Cu doping creates unstable Cu^(2+)-O-Cu^(2+)sites and shifts the barrier to theα-C-H cleavage.展开更多
Compared to conventional electrocatalytic water splitting,electrocatalytic ethanol oxidation reaction(EOR)along with hydrogen production is considered a more energy-efficient strategy.Herein,we prepared a type of nove...Compared to conventional electrocatalytic water splitting,electrocatalytic ethanol oxidation reaction(EOR)along with hydrogen production is considered a more energy-efficient strategy.Herein,we prepared a type of novel quaternary alloy catalyst(PtAuCuNi@NF)that exhibits excellent activity for EOR(0.215 V at 10 mA cm^(-2))and hydrogen evolution reaction(HER)(7 mV at 10 mA cm^(-2)).Experimental results demonstrated that both Cu and Ni modulated the electronic environment around Pt and Au.The electron-rich active center facilitates the rapid adsorption and dissociation of reactants and intermediates for both EOR and HER.Impressively,in the ethanol-assisted overall water splitting(E-OWS),a current density of 10 mA cm^(-2)was achieved at 0.28 V.Moreover,an advanced acid-base self-powered system(A-Bsps)that can achieve a self-powered voltage of 0.59 V was assembled.Accordingly,the self-driven hydrogen production with zero external power supply was realized by integrating A-Bsps with the E-OWS equipment.The interesting results can provide a feasible strategy for designing and developing advanced nanoalloy-based materials for clean energy integration and use in various fields.展开更多
Catalyst design relies heavily on electronic metal‐support interactions,but the metal‐support interface with an uncontrollable electronic or coordination environment makes it challenging.Herein,we outline a promisin...Catalyst design relies heavily on electronic metal‐support interactions,but the metal‐support interface with an uncontrollable electronic or coordination environment makes it challenging.Herein,we outline a promising approach for the rational design of catalysts involving heteroatoms as anchors for Pd nanoparticles for ethanol oxidation reaction(EOR)catalysis.The doped B and N atoms from dimethylamine borane(DB)occupy the position of the Ti_(3)C_(2) lattice to anchor the supported Pd nanoparticles.The electrons transfer from the support to B atoms,and then to the metal Pd to form a stable electronic center.A strong electronic interaction can be produced and the d‐band center can be shifted down,driving Pd into the dominant metallic state and making Pd nanoparticles deposit uniformly on the support.As‐obtained Pd/DB–Ti_(3)C_(2) exhibits superior durability to its counterpart(∼14.6% retention)with 91.1% retention after 2000 cycles,placing it among the top single metal anodic catalysts.Further,in situ Raman and density functional theory computations confirm that Pd/DB–Ti_(3)C_(2) is capable of dehydrogenating ethanol at low reaction energies.展开更多
The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot sy...The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot synthetic method to synthesize PdPb3 nanochains with well-defined shape,size and composition via a solution-phase reduction method.The morphology,composition distribution and structure characteristics of PdPb3 nanochains were investigated by transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Thanks to the unique structure,the as-obtained PdPb3 nanochains can manifest much higher mass activity(2523 mA·mg-1)and higher operation durability than commercial Pd/C(1272 mA·mg-1)during the EOR measurements.More importantly,further CO-stripping measurements indicate that the incorporation of Pb species could favor the oxidative removal of CO intermediates on the Pd electrode at the negative potential and enhance the EOR activity and stability,making it possible to develop highly active and durable electrocatalysts.展开更多
Fabrication of superior catalytic performance palladium-based catalysts with affordable cost is the key to develop direct ethanol fuel cell.Herein,Pd-decorated three-dimensional(3D)porous constructed from graphene oxi...Fabrication of superior catalytic performance palladium-based catalysts with affordable cost is the key to develop direct ethanol fuel cell.Herein,Pd-decorated three-dimensional(3D)porous constructed from graphene oxide(GO)and MXene combining with polystyrene(PS)particles as sacrificial templates(Pd/GO-MXene-PS)to elevate the catalytic performance for ethanol oxidation was proposed.The 3D porous interconnected structure of Pd/GO-MXene-PS was characterized by scanning electron microscope(SEM),transmission electron microscope(TEM)and Brunner−Emmet−Teller(BET).By optimizing the doping ratio of MXene to GO,the mass activity of Pd/GO_(5)-MXene_(5)-PS(2944.0 mA·mg^(−1))was 3.0 times higher than that of commercial Pd/C(950.4 mA·mg^(−1))toward ethanol oxidation in base solution.Meanwhile,the rotating disk electrode(RDE)results demonstrated that Pd/GO5-MXene5-PS had a faster kinetics of ethanol oxidation.The enhanced ethanol oxidation over Pd/GO5-MXene5-PS could attribute to the excellent 3D interconnected porous structure,large surface area,good conductivity and homogeneous Pd distribution.This work provided a new idea for creating 3D porous MXene composite materials in electrocatalysis.展开更多
Pd nanoparticles(Pd-NPs)were prepared and directly anchored on the surface of multi-walled carbon nanotubes(MWCNTs)in the absence of chemical reduction agent,where MWCNTs were used as both the chemical reduction agent...Pd nanoparticles(Pd-NPs)were prepared and directly anchored on the surface of multi-walled carbon nanotubes(MWCNTs)in the absence of chemical reduction agent,where MWCNTs were used as both the chemical reduction agent and the support substrate of Pd-NPs.Effect of various surfactants on the in situ deposition of PdNPs on MWCNTs was investigated.When MWCNTs were modified with a cationic surfactant(hexadecyl trimethyl ammonium bromide,CTAB),the amount of the Pd-NPs(Pd-NP/CTAB-MWCNT)generated by such an in situ deposition method gets a notable increase,and the size of the as-synthesized Pd-NPs becomes smaller,compared with those in the absence of any surfactant(Pd-NP/MWCNT)or in the presence of an anionic surfactant SDS(Pd-NP/SDS-MWCNT)and a neutral surfactant OP(PdNP/OP-MWCNT).Results show that the MWCNTs modified with CTAB are propitious to the in situ reduction of Pd2?.Among the prepared catalysts,Pd-NP/CTABMWCNT displays the highest electroactivity for ethanol oxidation in alkaline media.展开更多
metal oxide electronic interactions in composite electrocatalysts have a considerable impact on their catalytic capability.In this study,we successfully synthesized an electrocatalytic material composed of MoO_(3)/C s...metal oxide electronic interactions in composite electrocatalysts have a considerable impact on their catalytic capability.In this study,we successfully synthesized an electrocatalytic material composed of MoO_(3)/C speciessupported Pd nanoparticles(Pd-MoO_(3)/C)using a convenient hydrothermal method,which exhibited excellent catalytic activities for both ethanol oxidation and oxygen reduction in KOH media.The specific activity of PdMoO_(3)/C toward ethanol oxidation with MoO_(3)loading(40wt%)was~2.6 times greater than that for the commercial Pd/C(10 wt%)with the same Pd content.In particular,the activity could effectively hold up to~60%of its maximum activity after 500-cycle tests,demonstrating improved cyclical stability.Notably,the fast electron transfer kinetics toward oxygen reduction for Pd-MoO_(3)/C(40%)were also comparable to those of commercial Pt/C(20 wt%)catalysts.These superior electrochemical features are primarily derived from the stronger electronic coupling between Pd and MoO_(3)through charge transfer,which can supply more active centers and improve the anti-poisoning ability.Meanwhile,the MoO_(3)species in the Pd-MoO_(3)/C composite may provide additional benefits in terms of electrical conductivity and dispersion.展开更多
Rational design of low‐cost and efficient electrocatalysts for ethanol oxidation reaction(EOR)is imperative for electrocatalytic ethanol fuel cells.In this work,we developed a copper‐doped nickel oxyhydroxide(Cu‐do...Rational design of low‐cost and efficient electrocatalysts for ethanol oxidation reaction(EOR)is imperative for electrocatalytic ethanol fuel cells.In this work,we developed a copper‐doped nickel oxyhydroxide(Cu‐doped NiOOH)catalyst via in situ electrochemical reconstruction of a NiCu alloy.The introduction of Cu dopants increases the specific surface area and more defect sites,as well as forms high‐valence Ni sites.The Cu‐doped NiOOH electrocatalyst exhibited an excellent EOR performance with a peak current density of 227 mA·cm^(–2)at 1.72 V versus reversible hydrogen electrode,high Faradic efficiencies for acetate production(>98%),and excellent electrochemical stability.Our work suggests an attractive route of designing non‐noble metal based electrocatalysts for ethanol oxidation.展开更多
Direct ethanol fuel cell is a promising low temperature fuel cell,but its development is hindered by sluggish kinetics of anode catalysts for ethanol oxidation.Here a high efficient platinum/tin oxide/Graphene nanocom...Direct ethanol fuel cell is a promising low temperature fuel cell,but its development is hindered by sluggish kinetics of anode catalysts for ethanol oxidation.Here a high efficient platinum/tin oxide/Graphene nanocomposite is synthesized through a facile and environmentally benign method.The structure and morphology are carefully characterized by X-ray diffraction and Transmission electron microscopy,showing a clear platinum/tin oxide heterostructure uniformly dispersed on graphene support.This catalyst demonstrates the highest activity among the reported catalysts and much higher durability towards ethanol oxidation compared to conventional platinum nanocatalysts.The ultrahigh activity originates from promoted removal of poisoning carbon monoxide immediate species on platinum due to a strong electronic donating effect from both tin oxide and graphene,which is fully supported by carbon monoxide stripping and X-ray photoelectron spectroscopy analysis.Our platinum/tin oxide/Graphene appears to be a promising candidate for ethanol oxidation electrocatalysts.展开更多
Although most transition metals have been tested as the promoter to Pt for electrocatalysis toward fuel cell reactions,semi-conductor elements,such as Si,have hitherto not been examined.Here we report a simple synthes...Although most transition metals have been tested as the promoter to Pt for electrocatalysis toward fuel cell reactions,semi-conductor elements,such as Si,have hitherto not been examined.Here we report a simple synthesis of intermetallic Pt2Si electrode using magnetron sputtering and the electrocatalysis toward ethanol oxidation reaction(EOR).In comparison to Pt,the intermetallic Pt2Si surface turns out to be much more active in catalyzing the EOR:the onset potential shifts negatively by 150 mV,and the current density at 0.6 V increases by a magnitude of one order.Such an enormous enhancement in EOR catalysis is ascribed to the promotion effects of Si,which can not only provide active surface oxygenated species to accelerate the removal of COads,but also strongly alter the electronic property of Pt,as clearly indicated by the core-level shift in XPS spectrum.展开更多
The application of direct ethanol fuel cell(DEFC)has been bottlenecked by the sluggish ethanol oxidation reaction(EOR).Efficient electrocatalysts for the C-C bond cleavage are essential to promote EOR with high effici...The application of direct ethanol fuel cell(DEFC)has been bottlenecked by the sluggish ethanol oxidation reaction(EOR).Efficient electrocatalysts for the C-C bond cleavage are essential to promote EOR with high efficiency and C1 selectivity.Here,we prepared Rh-Cu alloy nano-dendrites(RhCu NDs)with abundant surface steps through controlled co-reduction,which exhibited significantly enhanced activity and C1 selectivity(0.47 m A cm_((ECSA))^(-2),472.4 mA mg_(Rh)^(-1),and 38.9%)than Rh NDs(0.32 mA cm((ECSA))-2,322.1 mA mgRh-1,and 21.4%)and commercially available Rh/C(0.18 mA cm_((ECSA))^(-2),265.4 mA mg_(Rh)^(-1),and 14.9%).Theoretical calculations and CO-stripping experiments revealed that alloying with Cu could modulate the surface electronic structures of Rh to resist CO-poisoning while strengthening ethanol adsorption.In situ Fourier transform infrared spectroscopy(FTIR)indicated that the surface steps on RhCu NDs further promoted the C-C bond cleavage to increase the C1 selectivity.Therefore,optimizing the surface geometric and electronic structures of nanocrystals by rational composition and morphology control can provide a promising strategy for developing practical DEFC devices.展开更多
Despite of considerable efforts on the MnO2-based catalytic combustion,the different structural and component requirements of MnO2 for gas-phase selective oxidation and complete oxidation largely remain unknown.By com...Despite of considerable efforts on the MnO2-based catalytic combustion,the different structural and component requirements of MnO2 for gas-phase selective oxidation and complete oxidation largely remain unknown.By comparing four types of MnO2 with different crystal structures(α,β,γandδ),γ-MnO2 was found to be the most efficient catalyst for both aerobic selective oxidation of ethanol and CO oxidation.The structural effect ofγ-MnO2 was further investigated by doping metal ions into the framework and by comparing the catalytic performance in the gas-phase aerobic oxidation of CO and ethanol.Among ten M-γ-MnO2 catalysts,Zn-γ-MnO2 showed the lowest temperature(160°C)for achieving 90%CO conversion.The CO oxidation activity of the M-γ-MnO2 catalysts was found to be more relevant to the surface acidity-basicity than the reducibility.In contrast,surface reducibility has been demonstrated to be more crucial in the gas-phase ethanol oxidation.Cu-γ-MnO2 with higher reducibility and more oxygen vacancies of Mn^2+/Mn^3+species exhibited higher catalytic activity in the selective ethanol oxidation.Cu-γ-MnO2 achieved the highest acetaldehyde yield(75%)and space-time-yield(5.4 g gcat^-1 h^-1)at 200°C,which are even comparable to the results obtained by the state-of-the-art silver and gold-containing catalysts.Characterization results and kinetic studies further suggest that the CO oxidation follows the lattice oxygen-based Mars-van Krevelen mechanism,whereas both surface lattice oxygen and adsorbed oxygen species involve in the ethanol activation.展开更多
Pd was electrochemically deposited on gold-coated quartz crystals at nanogram-level. The coulombic efficiency and initial nucleation and growth mechanism of potentiostatic Pd deposition were investigated via in situ e...Pd was electrochemically deposited on gold-coated quartz crystals at nanogram-level. The coulombic efficiency and initial nucleation and growth mechanism of potentiostatic Pd deposition were investigated via in situ electrochemical quartz crystal microbalance(EQCM). The coulombic efficieneies are 84%, 93% and 95% for Pd deposition at 0.3, 0.2 and 0.1 V(vs. SCE), respectively. The results of chronoamperometric measurements show that the Pd deposition proceeded by an instantaneous nucleation(at 0.3 V) or progressive nucleation(at 0.2 and 0.1 V) in a three-dimensional(3D) growth mode. The catalytic activity of Pd-based electrocatalyst for ethanol oxidation was characterized in an alkaline solution. It was found that the highest mass activity for ethanol oxidation on Pd-based electrocatalyst is 1.8× 10^4 A/(g Pd) deposited at 0.3 V for 5 s.展开更多
Quasi-one-dimensional NiO with a hierarchically porous structure was synthesized through a facile coordination−precipitation method with the coupling effect of ammonia and a post-calcination treatment.The electrocatal...Quasi-one-dimensional NiO with a hierarchically porous structure was synthesized through a facile coordination−precipitation method with the coupling effect of ammonia and a post-calcination treatment.The electrocatalytic properties of NiO fibers for the oxidation of ethanol were compared with those of NiO spheres.The results show that the fibrous NiO possesses a larger specific surface area of 140.153 m2/g and a lower electrical resistivity of 4.5×105Ω·m,leading to an impressively superior electrocatalytic activity to spherical NiO for ethanol oxidation in alkaline media.The current decay on fibrous NiO at 0.6 V in 100−900 s was 0.00003%,which is much lower than that of spherical NiO,indicating its better stability.The unique morphology and hierarchically porous structure give the fibrous NiO great potential to be used as an anodic electrocatalyst for direct ethanol fuel cells.展开更多
Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride he...Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.展开更多
Nucleophile oxidation reaction(NOR),represented by ethanol oxidation reaction(EOR),is a promising pathway to replace oxygen evolution reaction(OER).EOR can effectively reduce the driving voltage of hydrogen production...Nucleophile oxidation reaction(NOR),represented by ethanol oxidation reaction(EOR),is a promising pathway to replace oxygen evolution reaction(OER).EOR can effectively reduce the driving voltage of hydrogen production in direct water splitting.In this work,large current and high efficiency of EOR on a Ni,Fe layered double hydroxide(NiFe-LDH)catalyst were simultaneously achieved by a facile fluorination strategy.F in NiFe-LDH can reduce the activation energy of the dehydrogenation reaction,thus promoting the deprotonation process of NiFe-LDH to achieve a lower EOR onset potential.It also weakens the absorption of OH-and nucleophile electrooxidation products on the surface of NiFe-LDH at a higher potential,achieving a high current density and EOR selectivity,according to density functional theory calculations.Based on our experiment results,the optimized fluorinated NiFe-LDH catalyst achieves a low potential of 1.386 V to deliver a 10 mA cm^(-2)EOR.Moreover,the Faraday efficiency is greater than 95%,with a current density ranging from 10 to 250 mA cm^(-2).This work provides a promising pathway for an efficient and cost-effective NOR catalyst design for economic hydrogen production.展开更多
Dealloying by which the transition metal is partially or completely leached from an alloy precursor is an effective way to optimize the fundamental effects for further enhancing the electrocatalysis of a catalyst.Here...Dealloying by which the transition metal is partially or completely leached from an alloy precursor is an effective way to optimize the fundamental effects for further enhancing the electrocatalysis of a catalyst.Herein,to address the deficiencies associated with the commonly used dealloying methods,for example,electrochemical and sulfuric acid/nitric acid treatment,we report an acetic acid-assisted mild strategy to dealloy Cu atoms from the outer surface layers of CuPd alloy nanoparticles to achieve high-efficiency electrocatalysis for oxygen reduction and ethanol oxidation in an alkaline electrolyte.The leaching of Cu atoms by acetic acid exerts an additional compressive strain effect on the surface layers and exposes more active Pd atoms,which is beneficial for boosting the catalytic performance of a dealloyed catalyst for the oxygen reduction reaction(ORR)and the ethanol oxidation reaction(EOR).In particular,for ORR,the CuPd nanoparticles with a Pd/Cu molar ratio of 2:1 after acetic dealloying show a half-wave potential of 0.912 V(vs.RHE)and a mass activity of 0.213 AmgPd^(-1)at 0.9 V,respectively,while for EOR,the same dealloyed sample has a mass activity and a specific activity of 8.4 Amg^(-1)and 8.23 mA cm^(-2),respectively,much better than their dealloyed counterparts at other temperatures and commercial Pd/C as well as a Pt/C catalyst.展开更多
Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical reactions.However,the electrochemical performance can be further enhanced by fine-tune of the alloy composition.Although bina...Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical reactions.However,the electrochemical performance can be further enhanced by fine-tune of the alloy composition.Although binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy alloy.Herein Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd precursor.Through analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary system.However,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation reaction.The morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same protocol.The successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.展开更多
The electrochemical ethanol oxidation reaction(EOR) plays a crucial role in electrochemical hydrogen production and direct ethanol fuel cells, both vital for utilizing renewable energies. Ni-based catalysts are pivota...The electrochemical ethanol oxidation reaction(EOR) plays a crucial role in electrochemical hydrogen production and direct ethanol fuel cells, both vital for utilizing renewable energies. Ni-based catalysts are pivotal in enabling efficient EOR, leading to the formation of acetic acid/acetaldehyde or CO_(2). These can serve as alternative anodic oxidation reactions for oxygen evolution reaction(OER) in water electrolysis or the anodic reaction for direct ethanol fuel cells, respectively. This review explores recent advancements in EOR over Ni-based catalysts. It begins with an overview of EOR performance across various Ni-based catalysts, followed by an examination of the reaction chemistry, mechanism, and active sites.The review then delves into strategies for designing highly active Ni-based EOR catalysts. These strategies include promotion with transition metals, noble metals, nonmetals, and carbon materials, as well as creating amorphous structures, special morphologies, and single-atom catalysts. Additionally, it discusses the concept of self-supporting catalysts using three-dimensional porous substrates. Finally, the review highlights emerging methodologies that warrant further exploration, along with future directions for designing highly active and stable EOR catalysts.展开更多
The inefficiency of ethanol oxidation reaction(EOR)presents a significant obstacle in harnessing renewable biofuels with high energy density into electricity.Despite efforts,most Pt-based catalysts still suffer from d...The inefficiency of ethanol oxidation reaction(EOR)presents a significant obstacle in harnessing renewable biofuels with high energy density into electricity.Despite efforts,most Pt-based catalysts still suffer from drawbacks such as poor activity and susceptibility to CO poisoning,particularly in acidic conditions.Herein,we employed a physical laser-assisted approach to synthetize a PtPd alloy with a 1:1 atomic ratio.This alloy demonstrates remarkable performance in acidic EOR,boasting a high mass activity of 1.86 A·mgPt^(−1)and competitive resistance to poisoning.Combining in situ synchrotron radiation infrared spectroscopy with theoretical calculations,we reveal that the synergic interaction between Pt and Pd enhances both the adsorption of OH*intermediate and the dehydrogenation ability of ethanol.This work will prove the feasibility of synthesizing bimetallic alloys by a physical laser-assisted strategy and promote the development of advanced alloy electrocatalysts.展开更多
文摘Gold nanoparticles(AuNPs)supported on the Cu-doped LaMnO_(3)perovskites exhibit strong Au-Mn-Cu synergy in the aerobic oxidation of gaseous ethanol to acetaldehyde(AC).The Au/LaMnCuO_(3)catalysts achieve AC yields exceeding 90%and a space-time yield of 715 g_(AC)g_(AU)^(-1)h^(-1)at 225℃,outperforming reported catalysts.The outstanding performance is attributed to adjacent Cu^(+)and Mn^(2+)ions in the perovskite surface,which,together with nearby AuNPs,contribute to the high activity and stability.The best-performing catalyst contains a Cu/Mn ratio of 1/3 in the perovskite.Doping too much Cu into the perovskite leads to metallic Cu,suppressing catalyst performance.Density functional theory(reaction energetics,electronic structure analysis)and microkinetics simulations aided in understanding the synergy between Cu and Mn and the role of AuNPs.The reaction involves two H abstraction steps:(1)O-H cleavage of adsorbed ethanol by the basic perovskite lattice oxygen atom and(2)α-C-H cleavage by AuNPs,yielding AC and adsorbed water.Molecular O_(2)adsorbs in the oxygen vacancy(O_(V))formed by water removal,generating a peroxide anion(O_(2)^(2-))as the activated oxygen species.In the second part of the catalytic cycle,the basic O_(2)^(2-)species abstracts the H atom from another ethanol molecule,followed byα-C-H cleavage by AuNPs,AC production,and water removal.Water formation in the second part of the catalytic cycle is the rate-controlling step for Au/LaMnO_(3)and Au/LaMnCuO_(3)models.Moderate Cu doping enhances the essential Cu^(+)-OV-Mn^(2+)sites and lowers the barrier for water formation due to the weaker Cu-O bond than the Mn-O bond.In contrast,excessive Cu doping creates unstable Cu^(2+)-O-Cu^(2+)sites and shifts the barrier to theα-C-H cleavage.
基金supported by the Key projects of intergovernmental international cooperation in the Key R&D programs of the Ministry of Science and Technology of China(No.2021YFE0115800)the National Science Funding Committee of China(No.U20A20250)。
文摘Compared to conventional electrocatalytic water splitting,electrocatalytic ethanol oxidation reaction(EOR)along with hydrogen production is considered a more energy-efficient strategy.Herein,we prepared a type of novel quaternary alloy catalyst(PtAuCuNi@NF)that exhibits excellent activity for EOR(0.215 V at 10 mA cm^(-2))and hydrogen evolution reaction(HER)(7 mV at 10 mA cm^(-2)).Experimental results demonstrated that both Cu and Ni modulated the electronic environment around Pt and Au.The electron-rich active center facilitates the rapid adsorption and dissociation of reactants and intermediates for both EOR and HER.Impressively,in the ethanol-assisted overall water splitting(E-OWS),a current density of 10 mA cm^(-2)was achieved at 0.28 V.Moreover,an advanced acid-base self-powered system(A-Bsps)that can achieve a self-powered voltage of 0.59 V was assembled.Accordingly,the self-driven hydrogen production with zero external power supply was realized by integrating A-Bsps with the E-OWS equipment.The interesting results can provide a feasible strategy for designing and developing advanced nanoalloy-based materials for clean energy integration and use in various fields.
基金Key Research and Development Program of Zhejiang,Grant/Award Number:2021C03022National Natural Science Foundation of China,Grant/Award Numbers:22002104,22272115,22202145,22202146,22102112,22202147。
文摘Catalyst design relies heavily on electronic metal‐support interactions,but the metal‐support interface with an uncontrollable electronic or coordination environment makes it challenging.Herein,we outline a promising approach for the rational design of catalysts involving heteroatoms as anchors for Pd nanoparticles for ethanol oxidation reaction(EOR)catalysis.The doped B and N atoms from dimethylamine borane(DB)occupy the position of the Ti_(3)C_(2) lattice to anchor the supported Pd nanoparticles.The electrons transfer from the support to B atoms,and then to the metal Pd to form a stable electronic center.A strong electronic interaction can be produced and the d‐band center can be shifted down,driving Pd into the dominant metallic state and making Pd nanoparticles deposit uniformly on the support.As‐obtained Pd/DB–Ti_(3)C_(2) exhibits superior durability to its counterpart(∼14.6% retention)with 91.1% retention after 2000 cycles,placing it among the top single metal anodic catalysts.Further,in situ Raman and density functional theory computations confirm that Pd/DB–Ti_(3)C_(2) is capable of dehydrogenating ethanol at low reaction energies.
基金financially supported by the National Natural Science Foundation of China(Nos.21673150,21703146 and 51802206)the Natural Science Foundation of Jiangsu Province(Nos.BK20180097 and BK20180846)+2 种基金the Program of the Ministry of Education of China for Introducing Talents of Discipline to Universities(111 Project)the Collaborative Innovation Center of Suzhou Nano Science and Technology(NANO-CIC)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot synthetic method to synthesize PdPb3 nanochains with well-defined shape,size and composition via a solution-phase reduction method.The morphology,composition distribution and structure characteristics of PdPb3 nanochains were investigated by transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Thanks to the unique structure,the as-obtained PdPb3 nanochains can manifest much higher mass activity(2523 mA·mg-1)and higher operation durability than commercial Pd/C(1272 mA·mg-1)during the EOR measurements.More importantly,further CO-stripping measurements indicate that the incorporation of Pb species could favor the oxidative removal of CO intermediates on the Pd electrode at the negative potential and enhance the EOR activity and stability,making it possible to develop highly active and durable electrocatalysts.
基金financially supported by the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(No.A30B191410)the Sailing Project from Science and Technology Commission of Shanghai Municipality(No.17YF1406600)+6 种基金Chenguang Project Supported by Shanghai Municipal Education Commission(No.18CG68)Gaoyuan Discipline of Shanghai-Materials Science and Engineering(No.A30NH221903)the Open Project of Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices(Soochow University)(No.KS2022)Collaborative Innovation Center of Suzhou Nano Science&Technologythe 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devicesthe Project of Guangdong Provincial Education(No.2020KTSCX131)。
文摘Fabrication of superior catalytic performance palladium-based catalysts with affordable cost is the key to develop direct ethanol fuel cell.Herein,Pd-decorated three-dimensional(3D)porous constructed from graphene oxide(GO)and MXene combining with polystyrene(PS)particles as sacrificial templates(Pd/GO-MXene-PS)to elevate the catalytic performance for ethanol oxidation was proposed.The 3D porous interconnected structure of Pd/GO-MXene-PS was characterized by scanning electron microscope(SEM),transmission electron microscope(TEM)and Brunner−Emmet−Teller(BET).By optimizing the doping ratio of MXene to GO,the mass activity of Pd/GO_(5)-MXene_(5)-PS(2944.0 mA·mg^(−1))was 3.0 times higher than that of commercial Pd/C(950.4 mA·mg^(−1))toward ethanol oxidation in base solution.Meanwhile,the rotating disk electrode(RDE)results demonstrated that Pd/GO5-MXene5-PS had a faster kinetics of ethanol oxidation.The enhanced ethanol oxidation over Pd/GO5-MXene5-PS could attribute to the excellent 3D interconnected porous structure,large surface area,good conductivity and homogeneous Pd distribution.This work provided a new idea for creating 3D porous MXene composite materials in electrocatalysis.
基金supported by the National Natural Science Foundation of China (Nos. 21376070 and 20876038)Scientific Research Fund of Hunan Provincial Edu- cation Department (No. 11K023)Hunan Provincial Natural Science Foundation of China (14JJ2096)
文摘Pd nanoparticles(Pd-NPs)were prepared and directly anchored on the surface of multi-walled carbon nanotubes(MWCNTs)in the absence of chemical reduction agent,where MWCNTs were used as both the chemical reduction agent and the support substrate of Pd-NPs.Effect of various surfactants on the in situ deposition of PdNPs on MWCNTs was investigated.When MWCNTs were modified with a cationic surfactant(hexadecyl trimethyl ammonium bromide,CTAB),the amount of the Pd-NPs(Pd-NP/CTAB-MWCNT)generated by such an in situ deposition method gets a notable increase,and the size of the as-synthesized Pd-NPs becomes smaller,compared with those in the absence of any surfactant(Pd-NP/MWCNT)or in the presence of an anionic surfactant SDS(Pd-NP/SDS-MWCNT)and a neutral surfactant OP(PdNP/OP-MWCNT).Results show that the MWCNTs modified with CTAB are propitious to the in situ reduction of Pd2?.Among the prepared catalysts,Pd-NP/CTABMWCNT displays the highest electroactivity for ethanol oxidation in alkaline media.
基金financially supported by the Natural Science Foundation of Shanxi Province(No.201901D111277)the National Natural Science Foundation of China(No.21571119)+1 种基金the Graduate Science and Technology Innovation Project Foundation of Shanxi Normal University(No.2021DCXM71)the Program for New Century Excellent Talents in University(No.NCET-12-1035)。
文摘metal oxide electronic interactions in composite electrocatalysts have a considerable impact on their catalytic capability.In this study,we successfully synthesized an electrocatalytic material composed of MoO_(3)/C speciessupported Pd nanoparticles(Pd-MoO_(3)/C)using a convenient hydrothermal method,which exhibited excellent catalytic activities for both ethanol oxidation and oxygen reduction in KOH media.The specific activity of PdMoO_(3)/C toward ethanol oxidation with MoO_(3)loading(40wt%)was~2.6 times greater than that for the commercial Pd/C(10 wt%)with the same Pd content.In particular,the activity could effectively hold up to~60%of its maximum activity after 500-cycle tests,demonstrating improved cyclical stability.Notably,the fast electron transfer kinetics toward oxygen reduction for Pd-MoO_(3)/C(40%)were also comparable to those of commercial Pt/C(20 wt%)catalysts.These superior electrochemical features are primarily derived from the stronger electronic coupling between Pd and MoO_(3)through charge transfer,which can supply more active centers and improve the anti-poisoning ability.Meanwhile,the MoO_(3)species in the Pd-MoO_(3)/C composite may provide additional benefits in terms of electrical conductivity and dispersion.
文摘Rational design of low‐cost and efficient electrocatalysts for ethanol oxidation reaction(EOR)is imperative for electrocatalytic ethanol fuel cells.In this work,we developed a copper‐doped nickel oxyhydroxide(Cu‐doped NiOOH)catalyst via in situ electrochemical reconstruction of a NiCu alloy.The introduction of Cu dopants increases the specific surface area and more defect sites,as well as forms high‐valence Ni sites.The Cu‐doped NiOOH electrocatalyst exhibited an excellent EOR performance with a peak current density of 227 mA·cm^(–2)at 1.72 V versus reversible hydrogen electrode,high Faradic efficiencies for acetate production(>98%),and excellent electrochemical stability.Our work suggests an attractive route of designing non‐noble metal based electrocatalysts for ethanol oxidation.
基金grateful to the financial support from the Key Research and Development Project of Tianjin(18ZXJMTG00180)the National Nature Science Foundation of China(21433003)~~
文摘Direct ethanol fuel cell is a promising low temperature fuel cell,but its development is hindered by sluggish kinetics of anode catalysts for ethanol oxidation.Here a high efficient platinum/tin oxide/Graphene nanocomposite is synthesized through a facile and environmentally benign method.The structure and morphology are carefully characterized by X-ray diffraction and Transmission electron microscopy,showing a clear platinum/tin oxide heterostructure uniformly dispersed on graphene support.This catalyst demonstrates the highest activity among the reported catalysts and much higher durability towards ethanol oxidation compared to conventional platinum nanocatalysts.The ultrahigh activity originates from promoted removal of poisoning carbon monoxide immediate species on platinum due to a strong electronic donating effect from both tin oxide and graphene,which is fully supported by carbon monoxide stripping and X-ray photoelectron spectroscopy analysis.Our platinum/tin oxide/Graphene appears to be a promising candidate for ethanol oxidation electrocatalysts.
基金supported by the National Basic Research Program(2012CB932800,2012CB215503)the National Science Foundation of China(21125312,21203142)the Doctoral Fund of Ministry of Education of China(20110141130002)
文摘Although most transition metals have been tested as the promoter to Pt for electrocatalysis toward fuel cell reactions,semi-conductor elements,such as Si,have hitherto not been examined.Here we report a simple synthesis of intermetallic Pt2Si electrode using magnetron sputtering and the electrocatalysis toward ethanol oxidation reaction(EOR).In comparison to Pt,the intermetallic Pt2Si surface turns out to be much more active in catalyzing the EOR:the onset potential shifts negatively by 150 mV,and the current density at 0.6 V increases by a magnitude of one order.Such an enormous enhancement in EOR catalysis is ascribed to the promotion effects of Si,which can not only provide active surface oxygenated species to accelerate the removal of COads,but also strongly alter the electronic property of Pt,as clearly indicated by the core-level shift in XPS spectrum.
基金the financial support from the National Natural Science Foundation of China(Nos.21971012,21922502,21971017)the National Key Research and Development Program of China(No.2020YFB1506300)+1 种基金the Beijing Municipal Natural Science Foundation(No.JQ20007)the Beijing Institute of Technology Research Fund Program。
文摘The application of direct ethanol fuel cell(DEFC)has been bottlenecked by the sluggish ethanol oxidation reaction(EOR).Efficient electrocatalysts for the C-C bond cleavage are essential to promote EOR with high efficiency and C1 selectivity.Here,we prepared Rh-Cu alloy nano-dendrites(RhCu NDs)with abundant surface steps through controlled co-reduction,which exhibited significantly enhanced activity and C1 selectivity(0.47 m A cm_((ECSA))^(-2),472.4 mA mg_(Rh)^(-1),and 38.9%)than Rh NDs(0.32 mA cm((ECSA))-2,322.1 mA mgRh-1,and 21.4%)and commercially available Rh/C(0.18 mA cm_((ECSA))^(-2),265.4 mA mg_(Rh)^(-1),and 14.9%).Theoretical calculations and CO-stripping experiments revealed that alloying with Cu could modulate the surface electronic structures of Rh to resist CO-poisoning while strengthening ethanol adsorption.In situ Fourier transform infrared spectroscopy(FTIR)indicated that the surface steps on RhCu NDs further promoted the C-C bond cleavage to increase the C1 selectivity.Therefore,optimizing the surface geometric and electronic structures of nanocrystals by rational composition and morphology control can provide a promising strategy for developing practical DEFC devices.
文摘Despite of considerable efforts on the MnO2-based catalytic combustion,the different structural and component requirements of MnO2 for gas-phase selective oxidation and complete oxidation largely remain unknown.By comparing four types of MnO2 with different crystal structures(α,β,γandδ),γ-MnO2 was found to be the most efficient catalyst for both aerobic selective oxidation of ethanol and CO oxidation.The structural effect ofγ-MnO2 was further investigated by doping metal ions into the framework and by comparing the catalytic performance in the gas-phase aerobic oxidation of CO and ethanol.Among ten M-γ-MnO2 catalysts,Zn-γ-MnO2 showed the lowest temperature(160°C)for achieving 90%CO conversion.The CO oxidation activity of the M-γ-MnO2 catalysts was found to be more relevant to the surface acidity-basicity than the reducibility.In contrast,surface reducibility has been demonstrated to be more crucial in the gas-phase ethanol oxidation.Cu-γ-MnO2 with higher reducibility and more oxygen vacancies of Mn^2+/Mn^3+species exhibited higher catalytic activity in the selective ethanol oxidation.Cu-γ-MnO2 achieved the highest acetaldehyde yield(75%)and space-time-yield(5.4 g gcat^-1 h^-1)at 200°C,which are even comparable to the results obtained by the state-of-the-art silver and gold-containing catalysts.Characterization results and kinetic studies further suggest that the CO oxidation follows the lattice oxygen-based Mars-van Krevelen mechanism,whereas both surface lattice oxygen and adsorbed oxygen species involve in the ethanol activation.
基金Supported by the Guangdong Science and Technology Key Projects, China(Nos.2007A010700001, 2007B090400032)Guangzhou Science and Technology Key Projects, China(Nos.2007Z1-D0051, SKT[2007]17-11) the Scientific Research Foundation for Young Teachers of the Sun Yat-Sen University, China(No.2006-31000-1131214)
文摘Pd was electrochemically deposited on gold-coated quartz crystals at nanogram-level. The coulombic efficiency and initial nucleation and growth mechanism of potentiostatic Pd deposition were investigated via in situ electrochemical quartz crystal microbalance(EQCM). The coulombic efficieneies are 84%, 93% and 95% for Pd deposition at 0.3, 0.2 and 0.1 V(vs. SCE), respectively. The results of chronoamperometric measurements show that the Pd deposition proceeded by an instantaneous nucleation(at 0.3 V) or progressive nucleation(at 0.2 and 0.1 V) in a three-dimensional(3D) growth mode. The catalytic activity of Pd-based electrocatalyst for ethanol oxidation was characterized in an alkaline solution. It was found that the highest mass activity for ethanol oxidation on Pd-based electrocatalyst is 1.8× 10^4 A/(g Pd) deposited at 0.3 V for 5 s.
基金Project(51404306)supported by the National Natural Science Foundation of ChinaProject(JNJJ201613)supported by Jiana Foundation of Central South University,ChinaProject(2017YFC0210401)supported by the National Key Research and Development Program of China。
文摘Quasi-one-dimensional NiO with a hierarchically porous structure was synthesized through a facile coordination−precipitation method with the coupling effect of ammonia and a post-calcination treatment.The electrocatalytic properties of NiO fibers for the oxidation of ethanol were compared with those of NiO spheres.The results show that the fibrous NiO possesses a larger specific surface area of 140.153 m2/g and a lower electrical resistivity of 4.5×105Ω·m,leading to an impressively superior electrocatalytic activity to spherical NiO for ethanol oxidation in alkaline media.The current decay on fibrous NiO at 0.6 V in 100−900 s was 0.00003%,which is much lower than that of spherical NiO,indicating its better stability.The unique morphology and hierarchically porous structure give the fibrous NiO great potential to be used as an anodic electrocatalyst for direct ethanol fuel cells.
基金supported by the National Natural Science Foundation of China(No.22465009)the Education Department of Guizhou Province(No.2021312)the Foundation of Guizhou Province(No.2019-5666).
文摘Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.
基金the financial support from the National Natural Science Foundation of China(22197121)Knowledge Innovation Program of Wuhan-Basic Research(2022010801010202)Research Fund Program of Guangdong Provincial Key Laboratory of Fuel Cell Technology(FC202201)。
文摘Nucleophile oxidation reaction(NOR),represented by ethanol oxidation reaction(EOR),is a promising pathway to replace oxygen evolution reaction(OER).EOR can effectively reduce the driving voltage of hydrogen production in direct water splitting.In this work,large current and high efficiency of EOR on a Ni,Fe layered double hydroxide(NiFe-LDH)catalyst were simultaneously achieved by a facile fluorination strategy.F in NiFe-LDH can reduce the activation energy of the dehydrogenation reaction,thus promoting the deprotonation process of NiFe-LDH to achieve a lower EOR onset potential.It also weakens the absorption of OH-and nucleophile electrooxidation products on the surface of NiFe-LDH at a higher potential,achieving a high current density and EOR selectivity,according to density functional theory calculations.Based on our experiment results,the optimized fluorinated NiFe-LDH catalyst achieves a low potential of 1.386 V to deliver a 10 mA cm^(-2)EOR.Moreover,the Faraday efficiency is greater than 95%,with a current density ranging from 10 to 250 mA cm^(-2).This work provides a promising pathway for an efficient and cost-effective NOR catalyst design for economic hydrogen production.
基金the financial support provided by the National Natural Science Foundation of China(22075290,21972068,52164028)the Beijing Natural Science Foundation(Z200012)+3 种基金the State Key Laboratory of Multiphase Complex Systemsthe Institute of Process Engineeringthe Chinese Academy of Sciences(MPCS-2021-A-05)the Nanjing IPE Institute of Green Manufacturing Industry(E0010725).
文摘Dealloying by which the transition metal is partially or completely leached from an alloy precursor is an effective way to optimize the fundamental effects for further enhancing the electrocatalysis of a catalyst.Herein,to address the deficiencies associated with the commonly used dealloying methods,for example,electrochemical and sulfuric acid/nitric acid treatment,we report an acetic acid-assisted mild strategy to dealloy Cu atoms from the outer surface layers of CuPd alloy nanoparticles to achieve high-efficiency electrocatalysis for oxygen reduction and ethanol oxidation in an alkaline electrolyte.The leaching of Cu atoms by acetic acid exerts an additional compressive strain effect on the surface layers and exposes more active Pd atoms,which is beneficial for boosting the catalytic performance of a dealloyed catalyst for the oxygen reduction reaction(ORR)and the ethanol oxidation reaction(EOR).In particular,for ORR,the CuPd nanoparticles with a Pd/Cu molar ratio of 2:1 after acetic dealloying show a half-wave potential of 0.912 V(vs.RHE)and a mass activity of 0.213 AmgPd^(-1)at 0.9 V,respectively,while for EOR,the same dealloyed sample has a mass activity and a specific activity of 8.4 Amg^(-1)and 8.23 mA cm^(-2),respectively,much better than their dealloyed counterparts at other temperatures and commercial Pd/C as well as a Pt/C catalyst.
基金the support of National Natural Science Foundation of China(No.22175127).
文摘Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical reactions.However,the electrochemical performance can be further enhanced by fine-tune of the alloy composition.Although binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy alloy.Herein Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd precursor.Through analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary system.However,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation reaction.The morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same protocol.The successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.
基金funding from the National Natural Science Foundation of China (No. 22202065)Nanjing Tech University (No. 39801170)State Key Laboratory of MaterialsOriented Chemical Engineering (No. 38901218)。
文摘The electrochemical ethanol oxidation reaction(EOR) plays a crucial role in electrochemical hydrogen production and direct ethanol fuel cells, both vital for utilizing renewable energies. Ni-based catalysts are pivotal in enabling efficient EOR, leading to the formation of acetic acid/acetaldehyde or CO_(2). These can serve as alternative anodic oxidation reactions for oxygen evolution reaction(OER) in water electrolysis or the anodic reaction for direct ethanol fuel cells, respectively. This review explores recent advancements in EOR over Ni-based catalysts. It begins with an overview of EOR performance across various Ni-based catalysts, followed by an examination of the reaction chemistry, mechanism, and active sites.The review then delves into strategies for designing highly active Ni-based EOR catalysts. These strategies include promotion with transition metals, noble metals, nonmetals, and carbon materials, as well as creating amorphous structures, special morphologies, and single-atom catalysts. Additionally, it discusses the concept of self-supporting catalysts using three-dimensional porous substrates. Finally, the review highlights emerging methodologies that warrant further exploration, along with future directions for designing highly active and stable EOR catalysts.
基金supported by the National Natural Science Foundation of China(Nos.12025505,12105287,22002147,22179125,U21A20317,and 22373001)the National Key Research and Development Program of China(No.2021YFA1600800)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0450200)the Fundamental Research Funds for the Central Universities(No.KY2310000097)Xiaomi Young Talents Programsupported by the Supercomputing Center of the USTC.
文摘The inefficiency of ethanol oxidation reaction(EOR)presents a significant obstacle in harnessing renewable biofuels with high energy density into electricity.Despite efforts,most Pt-based catalysts still suffer from drawbacks such as poor activity and susceptibility to CO poisoning,particularly in acidic conditions.Herein,we employed a physical laser-assisted approach to synthetize a PtPd alloy with a 1:1 atomic ratio.This alloy demonstrates remarkable performance in acidic EOR,boasting a high mass activity of 1.86 A·mgPt^(−1)and competitive resistance to poisoning.Combining in situ synchrotron radiation infrared spectroscopy with theoretical calculations,we reveal that the synergic interaction between Pt and Pd enhances both the adsorption of OH*intermediate and the dehydrogenation ability of ethanol.This work will prove the feasibility of synthesizing bimetallic alloys by a physical laser-assisted strategy and promote the development of advanced alloy electrocatalysts.