The hydrogenation of petroleum resin(PR)is an effective process to prepare high value-added hydrogenated PR(HPR).However,the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogena...The hydrogenation of petroleum resin(PR)is an effective process to prepare high value-added hydrogenated PR(HPR).However,the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogenation still remains a challenge.Herein,a La promoted Ni-based catalyst is reported through the thermal reduction of quaternary Ni La Mg Al-layered double hydroxides(Ni La Mg Al-LDHs).The incorporation of La is beneficial to the reduction and stability of Ni particles with reduced particle size,and the increased alkalinity effectively mitigates the breakage of molecular chains of PR.As a result,the La promoted Ni-based catalyst exhibits high catalytic activity and excellent stability for PR hydrogenation.A hydrogenation degree of 95.4%and 96.1%can be achieved for HC_(5)PR and HC_(9) PR with less reduced softening point,respectively.Notably,the hydrogenation degree still maintains at 92.7%even after 100 hours’reaction,much better than that without La incorporation or prepared using conventional impregnation method.展开更多
The heterogeneous catalytic oxidation of toluene by O_(2)is an inherently safe and green route for production of benzaldehyde,but after more than fifty years of effort,it remains a great challenge.Here,we report the b...The heterogeneous catalytic oxidation of toluene by O_(2)is an inherently safe and green route for production of benzaldehyde,but after more than fifty years of effort,it remains a great challenge.Here,we report the best heterogeneous catalyst,TeO_(x)/MoVTeNbO,up to now for the green oxidation of toluene by O_(2)to benzaldehyde,balancing the catalyst activity,selectivity,and stability.The deposition of TeO_(x) endows the MoVTeNbO composite oxide with entirely new property for toluene oxidation and the surface engineering mechanism has been fully explained.The discrete TeO_(x) clusters on the surface,shielding the nonselective oxidation sites that interact strongly with the benzene ring of toluene molecule,allows toluene molecule to chemically adsorb to the surface perpendicularly and the methyl is then prone to oxidation to aldehyde on the reshaped selective oxidation sites,where V=O is the main active species responsible for continuously extracting hydrogen from methyl and implanting oxygen to form benzaldehyde.The TeO_(x) clusters participate in this reaction through variable valences and stabilize benzaldehyde by couple interaction with the–CHO group of benzaldehyde,thereby achieving high selectivity to benzaldehyde(>95%).The extended works indicate that the catalytic mechanism is effective in a series of selective oxidation of toluene homologues to corresponding aldehydes.展开更多
Identifying catalytically active sites and understanding the role of the environment surrounding the active sites on heterogeneous catalysis remains a challenge.Here we show the cooperative,multisite reactivity within...Identifying catalytically active sites and understanding the role of the environment surrounding the active sites on heterogeneous catalysis remains a challenge.Here we show the cooperative,multisite reactivity within an atomically precise nanocluster Ag_(4)Pt_(2)(SR)_(8)(SR=2,4-dimethylbenzenethiol)for electrochemical hydrogen evolution reaction.Our spectroscopic analysis coupled with the computational modeling indicate that the hydrogen production proceeds via a stepwise mechanism,with the hydrogen intermediate initially presenting on the apical sites of the S atoms sequentially to bind at the pyramidally shaped location containing Ag-Pt-Ag linkages.The adsorption of hydrogen species on surrounding ligands is found to perturb the electronic structure of catalytic sites and further regulate the affinity of hydrogen species with the metal center.More notably,the subtle interplay between the catalytic function and the surrounding environment indeed facilitates the hydrogen evolution on the Ag_(4)Pt_(2)(SR)_(8) catalyst with an overpotential of only 23.3 mV at a current density of 10 mA·cm^(−2),which not only overperforms most metal nanoclusters reported but is also comparable to a typical Pt/C catalyst under identical conditions.展开更多
The selective hydrogenation reactions play a key role in industrial manufacture of fine chemicals,which mainly rely on noble metal catalysts.Herein,a noble-metal-free hybrid photosystem is established,in which boron c...The selective hydrogenation reactions play a key role in industrial manufacture of fine chemicals,which mainly rely on noble metal catalysts.Herein,a noble-metal-free hybrid photosystem is established,in which boron carbonitride(BCN)and nickel bis-diphosphine complex(NiP)catalyze cooperatively the semi-hydrogenation of alkynes with high efficiency and excellent selectivity(>99%)under mild reaction conditions.展开更多
Selective adsorption of α,β-unsaturated aldehydes(α,β-UALs)is a prerequisite for the hydrogenation of α,β-UALs to high-value unsaturated alcohols,but a quantitative description of the interactions between the C=...Selective adsorption of α,β-unsaturated aldehydes(α,β-UALs)is a prerequisite for the hydrogenation of α,β-UALs to high-value unsaturated alcohols,but a quantitative description of the interactions between the C=C/C=O bond of α,β-UALs and the catalysts is still lacking.Herein,based on comprehensive density functional theory calculations,we developed a descriptor that combines the near-frontier molecular orbitals of the C=C/C=O bonds of α,β-UALs with the fundamental physical properties of single-atom catalysts(SACs)and considers the inner/outer coordination environment.All of the parameters used in this descriptor are easily accessible and interpretable,enabling an efficient assessment of the selectivity of SACs for the C=C/C=O bonds ofα,β-UALs.展开更多
基金financially supported by the National Natural Science Foundation of China(22078064)Natural Science Foundation of Fujian Province for Distinguished Young Scholar(2018J06002)。
文摘The hydrogenation of petroleum resin(PR)is an effective process to prepare high value-added hydrogenated PR(HPR).However,the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogenation still remains a challenge.Herein,a La promoted Ni-based catalyst is reported through the thermal reduction of quaternary Ni La Mg Al-layered double hydroxides(Ni La Mg Al-LDHs).The incorporation of La is beneficial to the reduction and stability of Ni particles with reduced particle size,and the increased alkalinity effectively mitigates the breakage of molecular chains of PR.As a result,the La promoted Ni-based catalyst exhibits high catalytic activity and excellent stability for PR hydrogenation.A hydrogenation degree of 95.4%and 96.1%can be achieved for HC_(5)PR and HC_(9) PR with less reduced softening point,respectively.Notably,the hydrogenation degree still maintains at 92.7%even after 100 hours’reaction,much better than that without La incorporation or prepared using conventional impregnation method.
文摘The heterogeneous catalytic oxidation of toluene by O_(2)is an inherently safe and green route for production of benzaldehyde,but after more than fifty years of effort,it remains a great challenge.Here,we report the best heterogeneous catalyst,TeO_(x)/MoVTeNbO,up to now for the green oxidation of toluene by O_(2)to benzaldehyde,balancing the catalyst activity,selectivity,and stability.The deposition of TeO_(x) endows the MoVTeNbO composite oxide with entirely new property for toluene oxidation and the surface engineering mechanism has been fully explained.The discrete TeO_(x) clusters on the surface,shielding the nonselective oxidation sites that interact strongly with the benzene ring of toluene molecule,allows toluene molecule to chemically adsorb to the surface perpendicularly and the methyl is then prone to oxidation to aldehyde on the reshaped selective oxidation sites,where V=O is the main active species responsible for continuously extracting hydrogen from methyl and implanting oxygen to form benzaldehyde.The TeO_(x) clusters participate in this reaction through variable valences and stabilize benzaldehyde by couple interaction with the–CHO group of benzaldehyde,thereby achieving high selectivity to benzaldehyde(>95%).The extended works indicate that the catalytic mechanism is effective in a series of selective oxidation of toluene homologues to corresponding aldehydes.
基金support from the National Natural Science Foundation of China(grant nos.22125202,21932004,and 22302091)Natural Science Foundation of Jiangsu Province(grant no.BK20220033)Programs for high-level entrepreneurial and innovative talents introduction of Jiangsu Province,and China Postdoctoral Science Foundation(grant no.2022M721551).
文摘Identifying catalytically active sites and understanding the role of the environment surrounding the active sites on heterogeneous catalysis remains a challenge.Here we show the cooperative,multisite reactivity within an atomically precise nanocluster Ag_(4)Pt_(2)(SR)_(8)(SR=2,4-dimethylbenzenethiol)for electrochemical hydrogen evolution reaction.Our spectroscopic analysis coupled with the computational modeling indicate that the hydrogen production proceeds via a stepwise mechanism,with the hydrogen intermediate initially presenting on the apical sites of the S atoms sequentially to bind at the pyramidally shaped location containing Ag-Pt-Ag linkages.The adsorption of hydrogen species on surrounding ligands is found to perturb the electronic structure of catalytic sites and further regulate the affinity of hydrogen species with the metal center.More notably,the subtle interplay between the catalytic function and the surrounding environment indeed facilitates the hydrogen evolution on the Ag_(4)Pt_(2)(SR)_(8) catalyst with an overpotential of only 23.3 mV at a current density of 10 mA·cm^(−2),which not only overperforms most metal nanoclusters reported but is also comparable to a typical Pt/C catalyst under identical conditions.
基金supported by the National Natural Science Foundation of China(grant nos.22071026,21673040,21961142019,22032002,and U1905214)the National Key R&D Program of China(no.2018YFA0209301)the Chang Jiang Scholars Program of China(no.T2016147),and the 111 Project(no.D16008).
文摘The selective hydrogenation reactions play a key role in industrial manufacture of fine chemicals,which mainly rely on noble metal catalysts.Herein,a noble-metal-free hybrid photosystem is established,in which boron carbonitride(BCN)and nickel bis-diphosphine complex(NiP)catalyze cooperatively the semi-hydrogenation of alkynes with high efficiency and excellent selectivity(>99%)under mild reaction conditions.
基金supported by the National Natural Science Foundation of China (22373017, 22303085, and 21973013)the National Key R&D Program of China (2022YFA1503102)+2 种基金the National Natural Science Foundation of Fujian Province, China (2020J02025)Zhejiang Provincial Natural Science Foundation of China (LQ24B030014)the “Chuying Program” for the Top Young Talents of Fujian Province。
基金funded by National Natural Science Foundation of China(21973013 and 22072118)National Natural Science Foundation of Fujian Province,China(2020J02025)the Chuying Program for the Top Young Talents of Fujian Province.
文摘Selective adsorption of α,β-unsaturated aldehydes(α,β-UALs)is a prerequisite for the hydrogenation of α,β-UALs to high-value unsaturated alcohols,but a quantitative description of the interactions between the C=C/C=O bond of α,β-UALs and the catalysts is still lacking.Herein,based on comprehensive density functional theory calculations,we developed a descriptor that combines the near-frontier molecular orbitals of the C=C/C=O bonds of α,β-UALs with the fundamental physical properties of single-atom catalysts(SACs)and considers the inner/outer coordination environment.All of the parameters used in this descriptor are easily accessible and interpretable,enabling an efficient assessment of the selectivity of SACs for the C=C/C=O bonds ofα,β-UALs.
