Pretreatment of the carrier for supported catalysts can effectively improve the strong metal-support interaction(SMSI)and increase the dispersion of precious metals,which are critical to many important catalytic react...Pretreatment of the carrier for supported catalysts can effectively improve the strong metal-support interaction(SMSI)and increase the dispersion of precious metals,which are critical to many important catalytic reactions.In this work,we tuned SMSI on Pd/TiO_(2)catalysts through inducing surface defects of TiO_(2)by pretreated with different atmospheres(H_(2)/N_(2),N_(2),O_(2)/N_(2))at the high temperature(800℃).Multiple characterization results illustrated that surface defects anchored Pd species and thus enhanced their dispersion.During reduction,Ti^(3+)species formed and transferred onto the metallic Pd species and then induced SMSI,which effectively stabilize Pd species in the metallic state.The stronger MSI,the more stability of Pd species.As a case,Pd/TiO_(2)–800H_(2),with strongest MSI,displayed the best HCHO oxidation performance at low temperature(10℃).展开更多
Spatial isolation of different functional sites at the nanoscale in multifunctional catalysts for steering reaction sequence and paths remains a major challenge.Herein,we reported the spatial separation of dual-site A...Spatial isolation of different functional sites at the nanoscale in multifunctional catalysts for steering reaction sequence and paths remains a major challenge.Herein,we reported the spatial separation of dual-site Au and RuO_(2)on the nanosurface of TiO_(2)(Au/TiO_(2)/RuO_(2))through the strong metal-support interaction(SMSI)and the lattice matching(LM)for robust photocatalytic hydrogen evolution.The SMSI between Au and TiO_(2)induced the encapsulation of Au nanoparticles by an impermeable TiO_(x)overlayer,which can function as a physical separation barrier to the permeation of the second precursor.The LM between RuO_(2)and rutile-TiO_(2)can increase the stability of RuO_(2)/TiO_(2)interface and thus prevent the aggregation of dual-site Au and RuO_(2)in the calcination process of removing TiO_(x)overlayer of Au.The photocatalytic hydrogen production is used as a model reaction to evaluate the performance of spatially separated dual-site Au/TiO_(2)/RuO_(2)catalysts.The rate of hydrogen production of the Au/TiO_(2)/RuO_(2)is as high as 84μmol h^(−1)g^(−1)under solar light irradiation without sacrificial agents,which is 2.5 times higher than the reference Au/TiO_(2)and non-separated Au/RuO_(2)/TiO_(2)samples.Systematic characterizations verify that the spatially separated dual-site Au and RuO_(2)on the nanosurface of TiO_(2)can effectively separate the photo-generated carriers and lower the height of the Schottky barrier,respectively,under UV and visible light irradiation.This study provides new inspiration for the precise construction of different sites in multifunctional catalysts.展开更多
The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucia...The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucial in supported catalysts'activity and stability.However,for redox reactions catalyzed in environmental catalysis,the enhancement mechanism of SMSI-induced oxygen vacancy and electron transfer needs to be clarified.Additionally,the precise control of SMSI interface sites remains to be fully understood.Here we provide a systematic review of SMSI's catalytic mechanisms and control strategies in purifying gaseous pollutants,treating organic wastewater,and valorizing biomass solid waste.We explore the adsorption and activation mechanisms of SMSI in redox reactions by examining interfacial electron transfer,interfacial oxygen vacancy,and interfacial acidic sites.Furthermore,we develop a precise regulation strategy of SMSI from systematical perspectives of interface effect,crystal facet effect,size effect,vip ion doping,and modification effect.Importantly,we point out the drawbacks and breakthrough directions for SMSI regulation in environmental catalysis,including partial encapsulation strategy,size optimization strategy,interface oxygen vacancy strategy,and multi-component strategy.This review article provides the potential applications of SMSI and offers guidance for its controlled regulation in environmental catalysis.展开更多
Strong metal-support interaction(SMSI)has a great impact on the activity and selectivity of heterogeneous catalysts,which was usually adjusted by changing reduction temperature or processing catalyst in different atmo...Strong metal-support interaction(SMSI)has a great impact on the activity and selectivity of heterogeneous catalysts,which was usually adjusted by changing reduction temperature or processing catalyst in different atmosphere.However,few researches concentrate on modulating SMSI through regulating the structure of the support.Herein,we show how changing the surface environment of the anatase TiO_(2)(B–TiO_(2))can be used to modulate the SMSI.The moderate TiOx overlayer makes the Ni metal highly dispersed on the high specific surface area of support,resulting in a substantially enhanced CO_(2)methanation rate.Besides,a novel phenomenon was observed that boron dopants promote the for-mation of the B–O–Ti interface site,enhancing the catalytic performance of CO_(2)hydrogenation.DFT calculations confirm that the B–O–Ti structure facilitates the activation of CO_(2)and further hydrogenation to methane.展开更多
Propane dehydrogenation(PDH) provides an alternative route for producing propylene. Herein, we demonstrates that h-BN is a promising support of Pt-based catalysts for PDH. The Pt catalysts supported on h-BN were prepa...Propane dehydrogenation(PDH) provides an alternative route for producing propylene. Herein, we demonstrates that h-BN is a promising support of Pt-based catalysts for PDH. The Pt catalysts supported on h-BN were prepared by an impregnation method using Pt(NH_(3))_(4)(NO_(3))_(2) as metal precursors. It has been found that the Pt/BN catalyst undergoing calcination and reduction is highly stable in both PDH reaction and coke-burning regeneration, together with low coke deposition and outstanding propylene selectivity(99%). Detailed characterizations reveal that the high coke resistance and high propylene selectivity of the Pt/BN catalyst are derived not only from the absence of acidity on BN support, but also from the calcination-induced and reduction-adjusted strong metal-support interaction(SMSI) between Pt and BN, which causes the partial encapsulation of Pt particles by BO_(x) overlayers. The BO_(x) overlayers can block the low-coordinated Pt sites and constrain Pt particles into smaller ensembles, suppressing side reactions such as cracking and deep dehydrogenation. Moreover, the BO_(x) overlayers can effectively inhibit Pt sintering by the spatial isolation of Pt during periodic reaction-regeneration cycles. In this work, the catalyst support for PDH is expanded to nonoxide BN, and the understanding of SMSI between Pt and BN will provide rational design strategy for BN-based catalysts.展开更多
Oxide supports modify electronic structures of supported metal nanoparticles,and then affect the catalytic activity associated with the so-called strong metal-support interaction(SMSI).We herein report the strong infl...Oxide supports modify electronic structures of supported metal nanoparticles,and then affect the catalytic activity associated with the so-called strong metal-support interaction(SMSI).We herein report the strong influence of SMSI employing Ni_(4)/α-MoC(111) and defective Ni_(4)/MgO(100) catalysts used for dry reforming of methane(DRM,CO_(2)+CH_4→2 CO+2 H_(2)) by using density functional theory(DFT) and kinetic Monte Carlo simulation(KMC).The results show that α-MoC(111) and MgO(100) surface have converse electron and structural effect for Ni_(4) cluster.The electrons transfer from a-MoC(111) surface to Ni atoms,but electrons transfer from Ni atoms to MgO(100) surface;an extensive tensile strain is greatly released in the Ni lattice by MgO,but the extensive tensile strain is introduced in the Ni lattice by α-MoC.As a result,although both catalysts show good stability,H_(2)/CO ratio on Ni_(4)/α-MoC(111) is obviously larger than that on Ni_(4)/MgO(100).The result shows that Ni/α-MoC is a good catalyst for DRM reaction comparing with Ni/MgO catalyst.展开更多
Interactions between metals and supports are of fundamental interest in heterogeneous catalysis, Noble metal particles supported on transition metal oxides (TMO) may undergo a so-called strong metal-support interactio...Interactions between metals and supports are of fundamental interest in heterogeneous catalysis, Noble metal particles supported on transition metal oxides (TMO) may undergo a so-called strong metal-support interaction via encapsulation. This perspective addresses catalytic properties of the metal catalysts in the SMSI state which can be explained on the basis of complementary studies. The electronic geometric and bifunctional effects originating from strong metal-support interactions (SMSI) that are responsible for the catalyst’s activity, selectivity, and stability are key factors that determine performance. A series of Pd-Sb supported on different metal oxide (<em>i.e.</em> SiO<sub>2</sub>, <em>γ</em>-Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and ZrO<sub>2</sub>) were prepared by the impregnation method. The catalysts were characterized by N<sub>2</sub> adsorption (BET-SA and pore size distribution), TEM (transmission electron microscope), TPR (temperature-programmed reduction), CO-chemisorption, the structural characterization of Pd (dispersity, surface area), interaction between Pd and Sb<sub>2</sub>O<sub>3</sub> and also the influence of the nature of the support were investigated. SiO<sub>2</sub> supported Pd catalyst exhibited the highest surface area (192.6 m<sup>2</sup>/g) and pore volume (0.542 cm<sup>3</sup>/g) compared to the other supported oxides catalysts. The electron micrographs of these catalysts showed a narrow size particle distribution of Pd, but with varying sizes which in the range from 1 to 10 nm, depending on the type of support used. The results show almost completely suppressed of CO chemisorption when the catalysts were subjected to high temperature reduction (HTR), this suppression was overcome by oxidation of a reduced Pd/MeOx catalysts followed by re-reduction in hydrogen at 453 K low temperature reduction (LTR), almost completely restored the normal chemisorptive properties of the catalysts, this suppression was attributed by SbOx species by a typical SMSI effect as known for other reducible supports such as TiO<sub>2</sub>, ZrO<sub>2</sub>, CeO<sub>2</sub>, and Nb<sub>2</sub>O<sub>5</sub>.展开更多
基金supported by the Youth Innovation Promotion Association,CAS(No.2020310)the Science and Technology Planning Project of Xiamen City(No.3502Z20191021)the Science and Technology Innovation“2025”major program in Ningbo(No.2022Z028)。
文摘Pretreatment of the carrier for supported catalysts can effectively improve the strong metal-support interaction(SMSI)and increase the dispersion of precious metals,which are critical to many important catalytic reactions.In this work,we tuned SMSI on Pd/TiO_(2)catalysts through inducing surface defects of TiO_(2)by pretreated with different atmospheres(H_(2)/N_(2),N_(2),O_(2)/N_(2))at the high temperature(800℃).Multiple characterization results illustrated that surface defects anchored Pd species and thus enhanced their dispersion.During reduction,Ti^(3+)species formed and transferred onto the metallic Pd species and then induced SMSI,which effectively stabilize Pd species in the metallic state.The stronger MSI,the more stability of Pd species.As a case,Pd/TiO_(2)–800H_(2),with strongest MSI,displayed the best HCHO oxidation performance at low temperature(10℃).
基金supported by the National Key Research and Development Program of China(No.2017YFB0405400)Shandong Provincial Natural Science Foundation(Nos.ZR2019BB025 and ZR2018ZC0842)the Project of 4"20 items of University"ofjinan(No.2018GXRC031).
文摘Spatial isolation of different functional sites at the nanoscale in multifunctional catalysts for steering reaction sequence and paths remains a major challenge.Herein,we reported the spatial separation of dual-site Au and RuO_(2)on the nanosurface of TiO_(2)(Au/TiO_(2)/RuO_(2))through the strong metal-support interaction(SMSI)and the lattice matching(LM)for robust photocatalytic hydrogen evolution.The SMSI between Au and TiO_(2)induced the encapsulation of Au nanoparticles by an impermeable TiO_(x)overlayer,which can function as a physical separation barrier to the permeation of the second precursor.The LM between RuO_(2)and rutile-TiO_(2)can increase the stability of RuO_(2)/TiO_(2)interface and thus prevent the aggregation of dual-site Au and RuO_(2)in the calcination process of removing TiO_(x)overlayer of Au.The photocatalytic hydrogen production is used as a model reaction to evaluate the performance of spatially separated dual-site Au/TiO_(2)/RuO_(2)catalysts.The rate of hydrogen production of the Au/TiO_(2)/RuO_(2)is as high as 84μmol h^(−1)g^(−1)under solar light irradiation without sacrificial agents,which is 2.5 times higher than the reference Au/TiO_(2)and non-separated Au/RuO_(2)/TiO_(2)samples.Systematic characterizations verify that the spatially separated dual-site Au and RuO_(2)on the nanosurface of TiO_(2)can effectively separate the photo-generated carriers and lower the height of the Schottky barrier,respectively,under UV and visible light irradiation.This study provides new inspiration for the precise construction of different sites in multifunctional catalysts.
基金National Key Research and Development Program of China(2022YFE0135000)National Natural Science Foundation of China(42175123、42107125)Fundamental Research Funds for the Central Universities,Nankai University(63231205).
文摘The strong metal-support interaction(SMSI)in supported catalysts plays a dominant role in catalytic degradation,upgrading,and remanufacturing of environmental pollutants.Previous studies have shown that SMSI is crucial in supported catalysts'activity and stability.However,for redox reactions catalyzed in environmental catalysis,the enhancement mechanism of SMSI-induced oxygen vacancy and electron transfer needs to be clarified.Additionally,the precise control of SMSI interface sites remains to be fully understood.Here we provide a systematic review of SMSI's catalytic mechanisms and control strategies in purifying gaseous pollutants,treating organic wastewater,and valorizing biomass solid waste.We explore the adsorption and activation mechanisms of SMSI in redox reactions by examining interfacial electron transfer,interfacial oxygen vacancy,and interfacial acidic sites.Furthermore,we develop a precise regulation strategy of SMSI from systematical perspectives of interface effect,crystal facet effect,size effect,vip ion doping,and modification effect.Importantly,we point out the drawbacks and breakthrough directions for SMSI regulation in environmental catalysis,including partial encapsulation strategy,size optimization strategy,interface oxygen vacancy strategy,and multi-component strategy.This review article provides the potential applications of SMSI and offers guidance for its controlled regulation in environmental catalysis.
基金supported by National Natural Science Foundation of China(21773053)Advanced Talents Incubation Program of Hebei University(801260201019)+1 种基金Research Innovation Team of College of Chemistry and Environmental Science of Hebei University(hxkytd-py2102)the support of the High-Performance Computing Center of Hebei University。
文摘Strong metal-support interaction(SMSI)has a great impact on the activity and selectivity of heterogeneous catalysts,which was usually adjusted by changing reduction temperature or processing catalyst in different atmosphere.However,few researches concentrate on modulating SMSI through regulating the structure of the support.Herein,we show how changing the surface environment of the anatase TiO_(2)(B–TiO_(2))can be used to modulate the SMSI.The moderate TiOx overlayer makes the Ni metal highly dispersed on the high specific surface area of support,resulting in a substantially enhanced CO_(2)methanation rate.Besides,a novel phenomenon was observed that boron dopants promote the for-mation of the B–O–Ti interface site,enhancing the catalytic performance of CO_(2)hydrogenation.DFT calculations confirm that the B–O–Ti structure facilitates the activation of CO_(2)and further hydrogenation to methane.
基金financially supported by the National Natural Science Foundation of China(21273049,22172037)the Guangdong Basic and Applied Basic Research Foundation(2021A1515010014)+1 种基金the Science and Technology Program of Guangzhou(201904010023)the CAS Key Laboratory of Renewable Energy(E029kf0901)。
文摘Propane dehydrogenation(PDH) provides an alternative route for producing propylene. Herein, we demonstrates that h-BN is a promising support of Pt-based catalysts for PDH. The Pt catalysts supported on h-BN were prepared by an impregnation method using Pt(NH_(3))_(4)(NO_(3))_(2) as metal precursors. It has been found that the Pt/BN catalyst undergoing calcination and reduction is highly stable in both PDH reaction and coke-burning regeneration, together with low coke deposition and outstanding propylene selectivity(99%). Detailed characterizations reveal that the high coke resistance and high propylene selectivity of the Pt/BN catalyst are derived not only from the absence of acidity on BN support, but also from the calcination-induced and reduction-adjusted strong metal-support interaction(SMSI) between Pt and BN, which causes the partial encapsulation of Pt particles by BO_(x) overlayers. The BO_(x) overlayers can block the low-coordinated Pt sites and constrain Pt particles into smaller ensembles, suppressing side reactions such as cracking and deep dehydrogenation. Moreover, the BO_(x) overlayers can effectively inhibit Pt sintering by the spatial isolation of Pt during periodic reaction-regeneration cycles. In this work, the catalyst support for PDH is expanded to nonoxide BN, and the understanding of SMSI between Pt and BN will provide rational design strategy for BN-based catalysts.
基金the National Natural Science Foundation of China (21776197 and 21776195)Shanxi Province Science Foundation for Youths (201701D211003)Key Research and Development Program of Shanxi Province (International Cooperation, 201903D421074) for their financial support。
文摘Oxide supports modify electronic structures of supported metal nanoparticles,and then affect the catalytic activity associated with the so-called strong metal-support interaction(SMSI).We herein report the strong influence of SMSI employing Ni_(4)/α-MoC(111) and defective Ni_(4)/MgO(100) catalysts used for dry reforming of methane(DRM,CO_(2)+CH_4→2 CO+2 H_(2)) by using density functional theory(DFT) and kinetic Monte Carlo simulation(KMC).The results show that α-MoC(111) and MgO(100) surface have converse electron and structural effect for Ni_(4) cluster.The electrons transfer from a-MoC(111) surface to Ni atoms,but electrons transfer from Ni atoms to MgO(100) surface;an extensive tensile strain is greatly released in the Ni lattice by MgO,but the extensive tensile strain is introduced in the Ni lattice by α-MoC.As a result,although both catalysts show good stability,H_(2)/CO ratio on Ni_(4)/α-MoC(111) is obviously larger than that on Ni_(4)/MgO(100).The result shows that Ni/α-MoC is a good catalyst for DRM reaction comparing with Ni/MgO catalyst.
文摘Interactions between metals and supports are of fundamental interest in heterogeneous catalysis, Noble metal particles supported on transition metal oxides (TMO) may undergo a so-called strong metal-support interaction via encapsulation. This perspective addresses catalytic properties of the metal catalysts in the SMSI state which can be explained on the basis of complementary studies. The electronic geometric and bifunctional effects originating from strong metal-support interactions (SMSI) that are responsible for the catalyst’s activity, selectivity, and stability are key factors that determine performance. A series of Pd-Sb supported on different metal oxide (<em>i.e.</em> SiO<sub>2</sub>, <em>γ</em>-Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and ZrO<sub>2</sub>) were prepared by the impregnation method. The catalysts were characterized by N<sub>2</sub> adsorption (BET-SA and pore size distribution), TEM (transmission electron microscope), TPR (temperature-programmed reduction), CO-chemisorption, the structural characterization of Pd (dispersity, surface area), interaction between Pd and Sb<sub>2</sub>O<sub>3</sub> and also the influence of the nature of the support were investigated. SiO<sub>2</sub> supported Pd catalyst exhibited the highest surface area (192.6 m<sup>2</sup>/g) and pore volume (0.542 cm<sup>3</sup>/g) compared to the other supported oxides catalysts. The electron micrographs of these catalysts showed a narrow size particle distribution of Pd, but with varying sizes which in the range from 1 to 10 nm, depending on the type of support used. The results show almost completely suppressed of CO chemisorption when the catalysts were subjected to high temperature reduction (HTR), this suppression was overcome by oxidation of a reduced Pd/MeOx catalysts followed by re-reduction in hydrogen at 453 K low temperature reduction (LTR), almost completely restored the normal chemisorptive properties of the catalysts, this suppression was attributed by SbOx species by a typical SMSI effect as known for other reducible supports such as TiO<sub>2</sub>, ZrO<sub>2</sub>, CeO<sub>2</sub>, and Nb<sub>2</sub>O<sub>5</sub>.
