查看更多>>摘要：The conversion of solar energy to produce clean hydrogen fuel through water splitting is an emerging strategy for efficiently storing solar energy in the form of solar fuel.This aligns with the increasing global demand for the development of an ideal energy alternative to fossil fuels that does not emit greenhouse gases.Electrochemical(EC)and photoelectrochemical(PEC)water splitting technologies have garnered significant attention worldwide for advanced hydrogen solar fuel production in recent decades.To achieve sustainable green H2 production,it is essential to create efficient catalyst materials that are low-cost and can replace expensive noble metal-based catalysts.These characteristics make them an ideal catalyst material for the process.Two-dimensional MXenes with Mn+1Xn structure have been iden-tified as a promising option for EC and PEC water splitting due to their superior hydrophilicity,metal-like conductivity,large surface area,and adjustable surface chemistry.Here,we present a summary of recent advancements in the synthesis and performance enhancement methods for MXene hybrid materials in hydrogen production through EC and PEC water splitting.Furthermore,we examine the challenges and insights associated with the rational design of MXene-based hybrid materials to facilitate efficient water splitting for sustainable solar fuel production.
查看更多>>摘要：The optimizing utilization of carbon resources has drawn wide attention all over the world,while exploit-ing the high-efficiency catalytic routes remains a challenge.Here,a direct methanol synthesis route is realized from pure CO and H2O over 10％Cu/t-ZrO2 catalyst,where the time yield of methanol is 144.43 mmol molCu-1 h-1 and the methanol selectivity in hydrocarbons is 100％.The Cu species highly dispersed in the t-ZrO2 support lead parts of them in the cationic state.The Cu+sites contribute to the dissociation of H2O,providing the H*source for methanol synthesis,while the formed Cu0 sites promote the absorption and transfer of H*during the reaction.Moreover,the H2O is even a better H resource than H2 due to its better dissociation effectivity in this catalytic system.The present work offers a new approach for methanol synthesis from CO and new insight into the process of supplying H donor.
查看更多>>摘要：The metal promoted In2O3 catalysts for CO2 hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In2O3.Herein,the Cu promoted In2O3 catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In2O3 catalyst shows significantly higher CO2 conversion and space time yield(STY)of methanol,compared to the un-promoted In2O3 cat-alyst.The loading of Cu facilitates the activation of both H2 and CO2 with the interface between the Cu cluster and defective In2O3 as the active site.The Cu/In2O3 catalyst takes the CO hydrogenation pathway for methanol synthesis from CO2 hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250 ℃,CO adsorption on Cu/In2O3 is stronger than that on In2O3,causing higher methanol selectivity.With increasing temperatures,the Cu catalyst aggregates,which leads to the forma-tion of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In2O3 catalysts,it can be concluded that the catalyst with stronger CO adsorption pos-sesses higher methanol selectivity.
查看更多>>摘要：Graphene's large theoretical surface area and high conductivity make it an attractive anode material for potassium-ion batteries(PIBs).However,its practical application is hindered by small interlayer distance and long ion transfer distance.Herein,this paper aims to address the issue by introducing MXene through a simple and scalable method for assembling graphene and realizing ultrahigh P doping content.The find-ings reveal that MXene and P-C bonds have a"pillar effect"on the structure of graphene,and the P-C bond plays a primary role.In addition,N/P co-doping introduces abundant defects,providing more active sites for K+storage and facilitating K+adsorption.As expected,the developed ultrahigh phosphorous/ni-trogen co-doped flexible reduced graphene oxide/MXene(NPrGM)electrode exhibits remarkable rever-sible discharge capacity(554 mA h g-1 at 0.05 A g-1),impressive rate capability(178 mA h g-1 at 2 A g-1),and robust cyclic stability(0.0005％decay per cycle after 10,000 cycles at 2 A g-1).Furthermore,the assembled activated carbon||NPrGM potassium-ion hybrid capacitor(PIHC)can deliver an impressive energy density of 131 W h kg-1 and stable cycling performance with 98.1％capacitance retention after 5000 cycles at 1 A g-1.Such a new strategy will effectively promote the practical application of graphene materials in PIBs/PIHCs and open new avenues for the scalable development of flexible films based on two-dimensional materials for potential applications in energy storage,thermal interface,and electro-magnetic shielding.
查看更多>>摘要：The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can signifi-cantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduc-tion reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt3CoxMn1-x ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L12 atomic structure,and the high-even dispersion on supports(L12-Pt3CoxMn1-x/sPt INPs/C).Electrochemical results present that the composition-optimized L12-Pt3Co0.7Mn0.3/sPt INPs/C exhibits the highest electrocatalytic activity among the series,which are also much better than those of the pris-tine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR elec-trocatalytic performance of L12-Pt3Co0.7Mn03/sPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocatalytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L12 atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.
查看更多>>摘要：Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO2 reduction(eCO2R),owing to their adaptable environments sur-rounding the copper metal centres.This investigation,employing density functional theory calculations,focuses on a novel family of binuclear Cu molecular catalysts.The modulation of their coordination con-figuration through the introduction of organic groups aims to assess their efficacy in converting CO2 to C2 products.Our findings highlight the crucial role of chemical valence state in shaping the characteristics of binuclear Cu catalysts,consequently influencing the eCO2R behaviour.Notably,the Cu(Ⅱ)Cu(Ⅱ)macrocy-cle catalyst exhibits enhanced suppression of the hydrogen evolution reaction(HER),facilitating proton transfer and the eCO2R process.Furthermore,we explore the impact of diverse electron-withdrawing and electron-donating groups coordinated to the macrocycle(R=-F,-H,and-OCH3)on the electron distri-bution in the molecular catalysts.Strategic placement of-OCH3 groups in the macrocycles leads to a favourable oxidation state of the Cu centres and subsequent C-C coupling to form C2 products.This research provides fundamental insights into the design and optimization of binuclear Cu molecular cat-alysts for the electrochemical conversion of CO2 to value-added C2 products.
查看更多>>摘要：As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC device.For this end,this review is written.Here,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in OSCs.Then,the characteristics of H-and J-aggregation and the methods to identify them were summarized.Next,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance.
查看更多>>摘要：Developing wide-temperature and high-safety lithium-ion batteries(LIBs)presents significant challenges attributed to the absence of suitable solvents possessing broad liquid range and non-flammability prop-erties.γ-Butyrolactone(GBL)has emerged as a promising solvent;however,its incompatibility with gra-phite anode has hindered its application.This limitation necessitates a comprehensive investigation into the underlying mechanisms and potential solutions.In this study,we achieve a molecular-level under-standing of the perplexing interphase formation process by employing in-situ spectroelectrochemical techniques and density function calculations.Our findings reveal that,even at high salt concentrations,GBL consistently occupies the primary Li+solvation sheath,leading to extensive GBL decomposition and the formation of a high-impedance and inorganic-poor solid-electrolyte interphase(SEI)layer.Contrary to manipulating solvation structures,our research demonstrates that the utilization of film-forming additives with higher reduction potential facilitates the pre-establishment of a robust SEI film on the graphite anode.This approach effectively inhibits GBL decomposition and significantly enhances the battery's lifespan.This study provides the first reported intrinsic understanding of the unique GBL-graphite incompatibility and offers valuable insights for the development of wide-temperature and high-safety LIBs.
查看更多>>摘要：The overall photocatalytic CO2 reduction reaction(OPCRR)that can directly convert CO2 and H2O into fuels represents a promising renewable energy conversion technology.As a typical redox reaction,the OPCRR involves two half-reactions:the CO2 reduction half-reaction(CRHR)and the water oxidation half-reaction(WOHR).Generally,both half-reactions can be promoted by adjusting the wettability of cat-alysts.However,there is a contradiction in wettability requirements for the two half-reactions.Specifically,CRHR prefers a hydrophobic surface that can accumulate more CO2 molecules on the active sites,ensuring the appropriate ratio of gas-phase(CO2)to liquid-phase(H2O)reactants.Conversely,the WOHR prefers a hydrophilic surface that can promote the departure of the gaseous product(O2)from the catalyst surface,preventing isolation between active sites and the reactant(H2O).Here,we successfully reconciled the contradictory wettability requirements for the CRHR and WOHR by creating an alternately hydrophobic catalyst.This was achieved through a selectively hydrophobic modification method and a charge-transfer-control strategy.Consequently,the collaboratively promoted CRHR and WOHR led to a significantly enhanced OPCRR with a solar-to-fuel conversion efficiency of 0.186％.Notably,in ethanol production,the catalyst exhibited a 10.64-fold increase in generation rate(271.44 pmol g-1 h-1)and a 4-fold increase in selectivity(55.77％)compared to the benchmark catalyst.This innovative approach holds great potential for application in universal overall reactions involving gas participation.
查看更多>>摘要：Aqueous zinc ion batteries(AZIBs)are one of the promising energy storage devices.However,uncon-trolled dendrite and side reactions have seriously hindered its further application.In this study,the metal-organic framework(MOF)functionalized glass fiber separator(GF-PFC-31)was used to regulate interfacial behavior of zinc metal anode,enabling the development of high-performance AZIBs.In PFC-31,there are π-π interactions between two adjacent benzene rings with a spacing of 3.199 Å.This spacing can block the passage of[Zn(H20)6]2+(8.6 Å in diameter)through the GF-PFC-31 separator to a certain extent,which promotes the deposition process of Zn ions.In addition,the sulfonic acid group(-SO3H)contained in GF-PFC-31 can form a hydrogen bonding network with H2O,which can provide a desolvation effect and reduce the side reaction.Consequently,GF-PFC-31 separator achieves uniform deposition of Zn ions.The Zn||GF-PFC-31||Zn symmetric cell exhibits stable cycle life(3000 h at 1.2 mA cm-2,2000 h at 0.3 mA cm-2,and 2000 h at 5.0 mA cm-2),and Zn||GF-PFC-31||MnO2 full cell with GF-PFC-31 separator can cycle for 1000 cycles at 1.2 A g-1 with capacity retention rate of 82.5％.This work provides a promis-ing method to achieve high-performance AZIBs.
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