The selective oxidation of methane under mild conditions remains the“Holy Grail of Catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active centers.Copper ...The selective oxidation of methane under mild conditions remains the“Holy Grail of Catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active centers.Copper nanoparticles were loaded onto TiO_(2) nanofibers using the photo-deposition method.The resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild conditions.Compared with previously reported catalysts,it delivers a superior performance of up to 2510.7 mmol·g_(Cu)^(-1)·h^(-1) productivity with a selectivity of around 100%at 80℃for 5 min.Microstructure characterizations and density functional theory(DFT)calculations indicate that TiO_(2) in the mixed phase of anatase and rutile significantly increases the Cu^(+)/CuO ratio of the supported Cu species,and this ratio is linearly related to the formation rate of oxygen-containing species.The CuI site promotes the generation of active O species from H_(2)O_(2) dissociation on Cu_(2)O(111).These active O species reduce the energy barrier for breaking the C-H bond of CH_(4),thus boosting the catalytic activity.The methane conversion mechanism was proposed as a methyl radical pathway to form CH_(3)OH and CH_(3)OOH,and then the generated CH_(3)OH is further oxidized to HOCH_(2)OOH.展开更多
The preparation of porous materials by the simple and low-cost methods is one of the hot topics in materials science.Here,the porous carbon-incorporated BN(P-CBN)was synthesized from the low-cost flour by a fermentati...The preparation of porous materials by the simple and low-cost methods is one of the hot topics in materials science.Here,the porous carbon-incorporated BN(P-CBN)was synthesized from the low-cost flour by a fermentation combined with freezedrying technology and ammonolysis.P-CBN-x samples not only maintain the pores of the fermented dough,but also produce abundant oxygen-containing boron species(B-OH,O-O and B-O).Due to the unique structural advantages,P-CBN-x catalysts exhibit remarkably better catalytic performance than bulk BN for the oxidative dehydrogenation of propane(ODHP)to produce olefins.Attractively,P-CBN-23 obtains high C_(3)H_(8 )conversion of 62.1%and olefin yield of 42.7%.In-situ DRIFTS experiments and DFT calculations demonstrate the B-OO-B species in P-CBN-x framework is the most active species for the C3H8activation and the B-O…O-B species can be readily regenerated by O_(2),thus promoting the conversion of propane to olefin.展开更多
基金supported by the National Natural Science Foundation of China(Nos.92145301,91845201,22002094,22102106,22309061)the Natural Science Foundation of Jilin Province(No.YDZJ202201ZYTS360).
文摘The selective oxidation of methane under mild conditions remains the“Holy Grail of Catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active centers.Copper nanoparticles were loaded onto TiO_(2) nanofibers using the photo-deposition method.The resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild conditions.Compared with previously reported catalysts,it delivers a superior performance of up to 2510.7 mmol·g_(Cu)^(-1)·h^(-1) productivity with a selectivity of around 100%at 80℃for 5 min.Microstructure characterizations and density functional theory(DFT)calculations indicate that TiO_(2) in the mixed phase of anatase and rutile significantly increases the Cu^(+)/CuO ratio of the supported Cu species,and this ratio is linearly related to the formation rate of oxygen-containing species.The CuI site promotes the generation of active O species from H_(2)O_(2) dissociation on Cu_(2)O(111).These active O species reduce the energy barrier for breaking the C-H bond of CH_(4),thus boosting the catalytic activity.The methane conversion mechanism was proposed as a methyl radical pathway to form CH_(3)OH and CH_(3)OOH,and then the generated CH_(3)OH is further oxidized to HOCH_(2)OOH.
基金financially supported by the major research projects of National Natural Science Foundation of China(92145301,91845201)National Natural Science Foundation of China(22002093,22002094)+3 种基金Liaoning Provincial Central Government Guides Local Science and Technology Development Funds(2022JH6/100100052)The Engineering Technology Research Center of Catalysis for Energy and Environment,Major Platform for Science and Technology of the Universities in Liaoning ProvinceLiaoning Province Key Laboratory for Highly Efficient Conversion and Clean Utilization of Oil and Gas Resourcesthe Engineering Research Center for Highly Efficient Conversion and Clean Use of Oil and Gas Resources of Liaoning Province。
文摘The preparation of porous materials by the simple and low-cost methods is one of the hot topics in materials science.Here,the porous carbon-incorporated BN(P-CBN)was synthesized from the low-cost flour by a fermentation combined with freezedrying technology and ammonolysis.P-CBN-x samples not only maintain the pores of the fermented dough,but also produce abundant oxygen-containing boron species(B-OH,O-O and B-O).Due to the unique structural advantages,P-CBN-x catalysts exhibit remarkably better catalytic performance than bulk BN for the oxidative dehydrogenation of propane(ODHP)to produce olefins.Attractively,P-CBN-23 obtains high C_(3)H_(8 )conversion of 62.1%and olefin yield of 42.7%.In-situ DRIFTS experiments and DFT calculations demonstrate the B-OO-B species in P-CBN-x framework is the most active species for the C3H8activation and the B-O…O-B species can be readily regenerated by O_(2),thus promoting the conversion of propane to olefin.