Nitrogen reduction reaction(NRR)under ambient conditions is always a long-standing challenge in science,due to the extreme difficulty in breaking the strong N≡N triple bond.The key to resolving this issue undoubtedly...Nitrogen reduction reaction(NRR)under ambient conditions is always a long-standing challenge in science,due to the extreme difficulty in breaking the strong N≡N triple bond.The key to resolving this issue undoubtedly lies in searching superior catalysts to efficiently activate and hydrogenate the stable nitrogen molecules.We herein evaluate the feasibility of WP_(2) for N2 activation and reduction,and first demonstrate WP_(2) with an impressive ammonia yield rate of 7.13 lg h^(-1)cm^(-2),representing a promising W-based catalyst for NRR.DFT analysis further reveals that the NRR catalysis on WP_(2) proceeds in a distal reaction pathway,and the exceptional NRR activity is originated from superior surface electron energy level matching between WP_(2) and NRR potential which facilitates the interfacial proton-coupled electron transfer dynamics.The successfully unraveling the intrinsic catalytic mechanism of WP_(2) for NRR could offer a powerful platform to manipulate the NRR activity by tuning the electron energy levels.展开更多
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 ...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.展开更多
Molybdenum disulfide (MoS2) has been recognized as one of the most promising candidates to replace precious Pt for hydrogen evolution reaction (HER) catalysis, due to the natural abundance, low cost, tunable electroni...Molybdenum disulfide (MoS2) has been recognized as one of the most promising candidates to replace precious Pt for hydrogen evolution reaction (HER) catalysis, due to the natural abundance, low cost, tunable electronic properties, and excellent chemical stability. Although notable processes have been achieved in the past decades, their performance is still far less than that of Pt. Searching effective strategies to boosting their HER performance is still the primary goal. In this review, the recent process of the electronic regulation of MoS2 for HER is summarized, including band structure engineering, electronic state modulation, orbital orientation regulation, interface engineering. Last, the key challenges and opportunities in the development of MoS2-based materials for electrochemical HER are also discussed.展开更多
The basal planes of transition metal dichalcogenides are basically inert for catalysis due to the absence of adsorption and activation sites,which substantially limit their catalytic application.Herein,a facile strate...The basal planes of transition metal dichalcogenides are basically inert for catalysis due to the absence of adsorption and activation sites,which substantially limit their catalytic application.Herein,a facile strategy to activate the basal plane of WS_(2) for hydrogen evolution reaction(HER)catalysis by phosphorous-induced electron density modulation is demonstrated.The optimized P doped WS_(2)(P-WS_(2))nanowires arrays deliver a low overpotential of 88 mV at 10 mA·cm^(-2)with a Tafel slope of 62 mV·dec^(-1)for HER,which is substantially better than the pristine counterpart.X-ray photoelectron spectroscopy confirms the surface electron densities of WS_(2) have been availably manipulated by P doping.Moreover,density functional theory(DFT)studies further prove P doping can redistribute the density of states(DOS)around EF,which endow the inert basal plane of PWS_(2) with edge-like catalytic activity toward hydrogen evolution catalysis.Our work offers a facile and effective approach to modulate the catalytic surface of WS_(2) toward highly efficient HER catalysis.展开更多
The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosh...The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosheets and porous nitrogen-doped carbon(Bi_(2)Se_(3−x)/NC)is prepared by selenizing bismuth metal-organic frameworks as a multifunctional sulfur host.The highly efficient immobilization-conversion on LiPSs is realized by the synergistic effect of structure construction strategy and defect engineering.It is found that Bi_(2)Se_(3−x)with the suitable amount of selenium vacancies achieves the best electrochemical performance due to the advantages of its structure and composition.These results confirm the intrinsic correlation between defects and catalysis,which are revealed by computational and experimental studies.Due to these superiorities,the developed sulfur electrodes exhibited admirable stability and a fairly lower capacity decay rate of approximately 0.0278%per cycle over 1,000 cycles at a 3 C rate.Even at the high sulfur loading of 6.2 mg·cm^(−2),the cathode still demonstrates a high discharge capacity of 455 mAh·g^(−1)at 1 C.This work may enlighten the development of mechanism investigation and design principles regarding sulfur catalysis toward high-performance Li-S batteries.展开更多
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 un...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.展开更多
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 diss...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.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.21771169,11804325,11722543,11875258,11505187)the National Key Research and Development Program of China(2017YFA0206703)+3 种基金Anhui Provincial Natural Science Foundation(BJ2060190077)USTC start-up fundingRecruitment Program of Global Expertthe Fundamental Research Funds for the Central Universities(WK2060190074,WK2060190081,WK2310000066)。
文摘Nitrogen reduction reaction(NRR)under ambient conditions is always a long-standing challenge in science,due to the extreme difficulty in breaking the strong N≡N triple bond.The key to resolving this issue undoubtedly lies in searching superior catalysts to efficiently activate and hydrogenate the stable nitrogen molecules.We herein evaluate the feasibility of WP_(2) for N2 activation and reduction,and first demonstrate WP_(2) with an impressive ammonia yield rate of 7.13 lg h^(-1)cm^(-2),representing a promising W-based catalyst for NRR.DFT analysis further reveals that the NRR catalysis on WP_(2) proceeds in a distal reaction pathway,and the exceptional NRR activity is originated from superior surface electron energy level matching between WP_(2) and NRR potential which facilitates the interfacial proton-coupled electron transfer dynamics.The successfully unraveling the intrinsic catalytic mechanism of WP_(2) for NRR could offer a powerful platform to manipulate the NRR activity by tuning the electron energy levels.
基金supported by the National Key R&D Program of China(Nos.2017YFA0700104 and 2018YFA0702001)the National Natural Science Foundation of China(Nos.21871238 and 22175163)+1 种基金the Fundamental Research Funds for the Central Universities(No.WK2060000016)the Youth Innovation Promotion Association of the Chinese Academy of Science(No.2018494).
文摘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.
基金the financial supports of the National Natural Science Foundation of China(Nos.21771169,51801075,and 11722543)the National Key Research and Development Program of China(No.2017YFA0206703)+1 种基金Anhui Provincial Natural Science Foundation(No.BJ2060190077)Re-cruitment Program of Global Expert,and the Fundamental Research Funds for the Central Universities(Nos.WK2060190074,WK2060190081,and WK2310000066).
文摘Molybdenum disulfide (MoS2) has been recognized as one of the most promising candidates to replace precious Pt for hydrogen evolution reaction (HER) catalysis, due to the natural abundance, low cost, tunable electronic properties, and excellent chemical stability. Although notable processes have been achieved in the past decades, their performance is still far less than that of Pt. Searching effective strategies to boosting their HER performance is still the primary goal. In this review, the recent process of the electronic regulation of MoS2 for HER is summarized, including band structure engineering, electronic state modulation, orbital orientation regulation, interface engineering. Last, the key challenges and opportunities in the development of MoS2-based materials for electrochemical HER are also discussed.
基金This work is supported by the National Natural Science Foundation of China(No.52122702)Natural Science Foundation of Heilongjiang Province of China(No.JQ2021E005)Fundamental Research Foundation for Universities of Heilongjiang Province(No.LGYC2018JQ006).
文摘The basal planes of transition metal dichalcogenides are basically inert for catalysis due to the absence of adsorption and activation sites,which substantially limit their catalytic application.Herein,a facile strategy to activate the basal plane of WS_(2) for hydrogen evolution reaction(HER)catalysis by phosphorous-induced electron density modulation is demonstrated.The optimized P doped WS_(2)(P-WS_(2))nanowires arrays deliver a low overpotential of 88 mV at 10 mA·cm^(-2)with a Tafel slope of 62 mV·dec^(-1)for HER,which is substantially better than the pristine counterpart.X-ray photoelectron spectroscopy confirms the surface electron densities of WS_(2) have been availably manipulated by P doping.Moreover,density functional theory(DFT)studies further prove P doping can redistribute the density of states(DOS)around EF,which endow the inert basal plane of PWS_(2) with edge-like catalytic activity toward hydrogen evolution catalysis.Our work offers a facile and effective approach to modulate the catalytic surface of WS_(2) toward highly efficient HER catalysis.
基金the National Natural Science Foundation of China(No.52122702)the Natural Science Foundation of Heilongjiang Province of China(No.JQ2021E005)the Fundamental Research Foundation for Universities of Heilongjiang Province(No.LGYC2018JQ006).
文摘The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosheets and porous nitrogen-doped carbon(Bi_(2)Se_(3−x)/NC)is prepared by selenizing bismuth metal-organic frameworks as a multifunctional sulfur host.The highly efficient immobilization-conversion on LiPSs is realized by the synergistic effect of structure construction strategy and defect engineering.It is found that Bi_(2)Se_(3−x)with the suitable amount of selenium vacancies achieves the best electrochemical performance due to the advantages of its structure and composition.These results confirm the intrinsic correlation between defects and catalysis,which are revealed by computational and experimental studies.Due to these superiorities,the developed sulfur electrodes exhibited admirable stability and a fairly lower capacity decay rate of approximately 0.0278%per cycle over 1,000 cycles at a 3 C rate.Even at the high sulfur loading of 6.2 mg·cm^(−2),the cathode still demonstrates a high discharge capacity of 455 mAh·g^(−1)at 1 C.This work may enlighten the development of mechanism investigation and design principles regarding sulfur catalysis toward high-performance Li-S batteries.
基金The work was supported by the National Natural Science Foundation of China(Nos.21771169 and 11722543)the National Key Research and Development Program of China(No.2017YFA0206703)+1 种基金Anhui Provincial Natural Science Foundation(No.BJ2060190077)Collaborative Innovation Program of Hefei Science Center,CAS,and the Fundamental Research Funds for the Central Universities(Nos.WK2060190074,WK2060190081,WK2310000066,and WK2060000015).
文摘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.
基金This work was supported by the National Natural Science Foundation of China(21771169,51801075,11722543)the National Key Research and Development Program of China(2017YFA0206703)+1 种基金Anhui Provincial Natural Science Foundation(BJ2060190077)Recruitment Program of Global Expert,and the Fundamental Research Funds for the Central Universities(WK2060190074,WK2060190081,WK2310000066).
文摘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.
