2023年度化学科学部基金项目评审工作综述

本文总结了2023年度化学科学部基金项目评审工作,介绍了化学科学部的项目申请、评审与资助情况,对资助存在的共性问题进行了分析,并提出下一年工作设想。

Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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.

Strong coupled spinel oxide with N-rGO for high-efficiency ORR/OER bifunctional electrocatalyst of Zn-air batteries

The high cost,scarcity,and poor stability of precious-metal-based catalysts have hindered their extensive application in energy conversion and storage.This stimulates the search for earth-abundant alternatives to replace noble metal electrocatalysts.Hence,in this study,we investigate a novel and low-cost bifunctional electrocatalyst consisting of ZnCoMnO_(4) anchored on nitrogen-doped graphene oxide(ZnCoMnO_(4)/N-rGO).Benefiting from the strong Co-N interaction in ZnCoMnO_(4) and the coupled conductive N-rGO,the catalysts exhibit high electrocatalytic activity.Moreover,density functional theory calculations support the dominant role of the strong Co-N electronic interaction,which leads to ZnCoMnO_(4)/N-rGO having more favorable binding energies with O2 and H_(2) O,resulting in fast reaction kinetics.The obtained ZnCoMnO_(4)/N-rGO electrocatalyst exhibits superb bifunctional activity,with a half-wave potential of 0.83 V for the oxygen reduction reaction and a low onset potential of 1.57 V for the oxygen evolution reaction in 0.1 M KOH solution.Furthermore,a Zn-air battery driven by the ZnCoMnO_(4)/N-rGO catalyst shows remarkable discharge/charge performance,with a power density of 138.52 mW cm^(-2) and longterm cycling stability for 48 h.This work provides a promising multifunctional electrocatalyst based on non-noble metals for the storage and conversion of renewable energy.

Synergistic interaction of Nb atoms anchored on g‐C_(3)N_(4) and H^(+) promoting high‐efficiency nitrogen reduction reaction

Nowadays catalytic nitrogen reduction reaction(NRR)by electrochemistry has attracted much attention because of its key role in producing the basic chemical product ammonia with low energy consumption.A stable and environmentally‐friendly single‐or multi‐atom catalyst with good performance in activity and selectivity is highly desired for NRR.From density functional theory calculations,the NRR mechanisms catalyzed by Nb monomer,dimer,trimer and tetramer anchored on graphitic carbon nitride(Nb_(x)@g‐C_(3)N_(4),x=1,2,3,4)have been deeply explored.It has been found that Nb_(3)@g‐C_(3)N_(4) exhibits the best catalytic ability among the four catalysts with the introduction of H+.A more stable intermediate(*NH_(2)+*H)can be found to reduce the huge free energy barrier of forming*NH_(3) from*NH_(2) directly in a multi‐atom system.By analyzing the density of states and projected crystal orbital Hamilton population,a synergistic effect among Nb atoms and the adsorbed H^(+)is responsible for reducing the overpotential of NRR.Furthermore,the competitive hydrogen evolution reaction is suppressed effectively.This work introduces a new insight in the reaction pathway in multi‐atoms for developing high‐efficiency NRR catalysts.

碱金属阳离子对硝酸根还原产氨反应的元素依赖性影响

Catalytic conversion of nitrate(NO_(3)^(-))pollutants into ammonia(NH_(3))offers a sustainable and promising route for both wastewater treatment and NH_(3)synthesis.Alkali cations are prevalent in nitrate solutions,but their roles beyond charge balance in catalytic NO_(3)^(-)conversion have been generally ignored.Herein,we report the promotion effect of K^(+)cations in KNO_(3)solution for NO_(3)^(-)reduction over a TiO_(2)-supported Ni single-atom catalyst(Ni_(1)/TiO_(2)).For photocatalytic NO_(3)^(-)reduction reaction,Ni_(1)/TiO_(2)exhibited a 1.9-fold NH_(3)yield rate with nearly 100%selectivity in KNO_(3)solution relative to that in NaNO_(3)solution.Mechanistic studies reveal that the K^(+)cations from KNO_(3)gradually bonded with the surface of Ni_(1)/TiO_(2),in situ forming a K-O-Ni moiety during reaction,whereas the Na^(+)ions were unable to interact with the catalyst in NaNO_(3)solution.The charge accumulation on the Ni sites induced by the incorporation of K atom promoted the adsorption and activation of NO_(3)^(-).Furthermore,the K-O-Ni moiety facilitated the multiple proton-electron coupling of NO_(3)^(-)into NH_(3)by stabilizing the intermediates.

2022年度化学科学部基金项目评审工作综述

本文总结了2022年度化学科学部评审工作情况,介绍了科学部各类项目申请与受理情况,并对申请与资助情况进行了分析,提出了未来项目评审工作思路与要点。

Cu_(2+1)O/CuO_(x)heterostructures promote the electrosynthesis of C^(2+)products from CO_(2)

Manipulating the oxidation state of Cu catalysts can significantly affect the selectivity and activity of electrocatalytic carbon dioxide reduction(CO_(2)RR).However,the thermodynamically favorable cathodic reduction to metallic states typically leads to catalytic deactivation.Herein,a defect construction strategy is employed to prepare crystalline/amorphous Cu_(2+1)O/CuO_(x)heterostructures(c/a-CuO_(x))with abundant Cu0 and Cuδ+(0<δ<1)sites for CO_(2)RR.The C^(2+)Faradaic efficiency of the heterostructured Cu catalyst is up to 81.3%,with partial current densities of 406.7 mA·cm−2.Significantly,real-time monitoring of the Cu oxidation state evolution by in-situ Raman spectroscopy confirms the stability of Cuδ+species under long-term high current density operation.Density functional theory(DFT)calculations further reveal that the adjacent Cu0 and Cuδ+sites in heterostructured c/a-CuO_(x)can efficiently reduce the energy barrier of CO coupling for C^(2+)products.

Selective and effective oxidation of 5-hydroxymethylfurfural by tuning the intermediates adsorption on Co-Cu-CN_(x)

Co-based catalysts are promising alternatives to precious metals for the selective and effective oxidation of 5-hydroxymethylfurfural(HMF)to the higher value-added 2,5-furandicarboxylic acid(FDCA).However,these catalysts still suffer from unsatisfactory activity and poor selectivity.A series of N-doped carbon-supported Co-based dual-metal nanoparticles(NPs)have been designed,among which the Co-Cu_(1.4)-CN_(x) exhibits enhanced HMF oxidative activity,achieving FDCA formation rates 4 times higher than that of pristine Co-CN_(x),with 100%FDCA selectivity.Density functional theory(DFT)calculations evidenced that the increased electron density on Co sites induced by Cu can mediate the positive electronegativity offset to downshift the dband center of Co-Cu_(1.4)-CN_(x),thus reducing the energy barriers for the conversion of HMF to FDCA.Such findings will support the development of superior non-precious metal catalysts for HMF oxidation.

Hierarchical iridium-based multimetallic alloy with double-core-shell architecture for efficient overall water splitting

The overall water splitting for hydrogen production is an effective strategy to resolve the environmental and energy crisis. Here, we report a facile approach to synthesize the Ir-based multimetallic, hierarchical, double-coreshelled architecture(HCSA) assisted by oil bath reaction for boosting overall water splitting in acidic environment. The Ir Ni Cu HCSA shows superior electrocatalytic activity for hydrogen evolution reaction(HER) and oxygen evolution reaction(OER), which are comparable to commercial Pt/C and better than IrO2. The Ir Ni Cu HCSA exhibits remarkably catalytic efficiency as bifunctional catalyst for overall water splitting where a low cell voltage of 1.53 V is enough to drive a current density of 10 mA cm^-2 and maintains stable for at least 20 h. The presented work for the design and synthesis of novel Ir-based multimetallic architecture paves the way for highperformance overall water splitting catalysis.

Behavior of gold-enhanced electrocatalytic performance of NiPtAu hollow nanocrystals for alkaline methanol oxidation

The Pt-based catalyst tends to be poisoned by carbon monoxide(CO)-like intermediates produced in fuel cell reactions,which seriously deteriorates its catalytic performance.Herein,noble metal Au with the capacity of resistance to CO-like intermediates poisoning was employed to construct multi-element Pt-based catalysts.Two trimetallic NiPtAu hollow nanocrystals(HNCs)with different surface Au contents were synthesized to explore the role of Au in electrocatalysis for alkaline methanol oxidation reaction(MOR).The trimetallic NiPtAu-SRAu HNCs catalyst with the relative rich Au content(15.17 at%)on surface exhibits a much lower CO oxidation peak potential than the other HNCs counterpart and 20 wt%Pt/C,which indicates the more exceptional CO-resisting performance.Besides,the MOR specific activity of NiPtAu-SRAu HNCs(31.52 mA cm^−2)is 7 times higher than that of 20wt%Pt/C(4.50 mA cm^−2).This enhancement in catalytic activity as well as anti-CO poisoning capability for NiPtAu-SRAu HNCs can be mainly ascribed to the weakened CO adsorption due to the exposure of Au atoms on NiPt surface evidenced by the experimental data and density functional theory calculations.This study not only investigates the role of Au in MOR catalysis but also could be helpful for designing and optimizing the electrocatalysts for high-active and robust fuel cell applications.

Accelerating water dissociation kinetics of Ni3N by tuning interfacial orbital coupling

The high unoccupied d band energy of Ni_(3)N basically results in weak orbital coupling with water molecule,consequently leading to slow water dissociation kinetics.Herein,we demonstrate Cr doping can downshift the unoccupied d orbitals and strengthen the interfacial orbital coupling to boost the water dissociation kinetics.The prepared Cr-Ni_(3)N/Ni displays an impressive overpotential of 37 mV at 10 mA·cmgeo-2,close to the benchmark Pt/C in 1.0 M KOH solution.Refined structural analysis reveals the Cr dopant exists as the Cr-N_(6)states and the average d band energy of Ni_(3)N is also lowered.Density functional theory calculation further confirms the downshifted d band energy can strengthen the orbital coupling between the unpaired electrons in O 2p and the unoccupied state of Ni 3d,which thus facilitates the water adsorption and dissociation.The work provides a new concept to achieve on-demand functions for hydrogen evolution catalysis and beyond,by regulating the interfacial orbital coupling.

Non-metallic electronic regulation in CuCo oxy-/thio-spinel as advanced oxygen evolution electrocatalysts

Developing cost-effective and high-performance oxygen evolution reaction(OER)electrocatalysts has become the intense research on pursuing emerging renewable energy conversion,in which exploring and investigating the intrinsic nature of efficient and stable Cu Co spinel catalysts toward OER in alkaline media is highly desirable.Herein,Cu1–xCo2+xO4oxy-spinel nanoflakes are fabricated by a facile hydrothermal method with the oxidation of ammonia water.In the same condition,Cu1–xCo2+xS4thio-spinel nanospheres are formed without oxidation.In OER process,the as-obtained Cu1–xCo2+xO4nanoflakes and Cu1–xCo2+xS4nanospheres possess the anodic overpotential of 267 and 297 m V in alkaline media to drive the current density of 10 m A/cm^2,respectively,outperforming the state-of-the-art noble metal catalyst of RuO2.X-ray photoelectron spectroscopy analysis exhibits the higher ratio value of Co(Ⅲ)/Co(Ⅱ)in Cu1–xCo2+xO4than that in Cu1–xCo2+xS4,suggesting that the stronglyelectronegative oxygen efficiently predominates in regulating valence states of Co active sites in spinel structures.Remarkably,density functional theory simulation further reveals that the increased valence state of Co could accelerate the electron exchange between catalysts and oxygen adsorbates during electrocatalysis,thus contributing to the higher OER activity of Cu1–xCo2+xO4catalysts.This work provides deep insight regarding the significance of non-metal element(O and S)in Cu Co spinel structure catalysts,as well as presents a promising approach to exploit higher performance and grasp the mechanism of various non-noblemetal spinel catalysts for water oxidation.

Orbital-regulated interfacial electronic coupling endows Ni3N with superior catalytic surface for hydrogen evolution reaction

The interstitial structure and weak Ni-N interaction of Ni3N lead to high unoccupied d orbital energy and unsuitable orbital orientation,which consequently results in weak orbital coupling with H2O and slow water dissociation kinetics for alkaline hydrogen evolution catalysis.Herein,we successfully lower the unoccupied d orbital energy of Ni3N to strengthen the interfacial electronic coupling by employing the strong electron pulling capability of oxygen dopants.The prepared O-Ni3N catalyst delivers an overpotential of 55 mV at 10 mA cm−2,very close to the commercial Pt/C.Refined structural characterization indicates the oxygen incorporation can decrease the electron densities around the Ni sites.Moreover,density functional theory calculation further proves the oxygen incorporation can create more unoccupied orbitals with lower energy and superior orientation for water adsorption and dissociation.The concept of orbital-regulated interfacial electronic coupling could offer a unique approach for the rational design of hydrogen evolution catalysts and beyond.