| The selective oxidation of alcohols is one of the most important branch in the production of chemicals.Multiple aldehydes and acid derivatives can be prepared by selective oxidation of alcohols,which has a wide range of applications in the fields of life sciences and organic synthesis intermediates.In particular,short-chain alcohols(including ethanol,glycerol.)and aromatic alcohols(including benzyl alcohol.)have been widely researched as model substrates because their hydroxyl groups are easy to activate.In addition,the oxidized derivatives of long-chain fatty alcohols also have high application value.However,the selective oxidation of long-chain fatty alcohols is currently a major challenge because of weak acidity and low activity of hydroxyl group.Octanol is often used as a model molecule to determine the effectiveness of a catalyst for the oxidation of aliphatic alcohols.Therefore,this paper focused on the oxidation reaction of octanol and taked the supported metal catalysts commonly used in the oxidation of alcohols as the research object.In view of the weak acidity of the long-chain fatty alcohol hydroxyl group and the difficulty of activation,this paper studied on the design and regulation of the surface-interfacial structure of the supported catalyst and its mechanism in the oxidation of octanol.Through the regulation of the catalysts preparation methods,the effect of the electronic structure of the active metal on the intrinsic activity of the octanol oxidation reaction was revealed.The Pt2+dominant active site was clarified,the reaction activity was strengthened,and based on the adjustment of the support coordination structure,the induction effect of the support coordination structure on the metal electronic structure was explored,and the Ti5c-O2c-Pt2+ interface dominant active site was clarified.The synergistic enhancement of reactivity and selectivity was achieved.Firstly,aiming at the regulation and control of the electronic structure of active components,the Pt/TiO2 catalysts were prepared by impregnation-calcination method and the sol-immobilization method,the effects of different catalysts preparation methods on the electronic structure of active metals and the oxidation performance of octanol were systematically explored through their comparison.The results showed that the TOF of the Pt/TiO2-air 500℃ is 5533 h-1,which is higher than 2733 h-1 of the Pt/TiO2-sol,which indicates that the former has higher catalytic intrinsic activity.In addition,under the same conversion,the two showed similar selectivity to the reaction product.Furthermore,XRD,HR-TEM,CO-FTIR,XPS,octanol-FTIR and other analytical methods revealed the internal relationship between the electronic structure of the catalyst and the intrinsic activity of the octanol oxidation reaction.The analysis of the electronic structure of the catalyst showed that compared with the sol fixation method,the characteristic peak of Pt element in the impregnation-air roasting method moved to the direction of high binding energy,and the proportion of Pt2+increased from 32%to 90%.In addition,the ratio of high-energy dominant active sites at the low coordination Pt corner and edge in the immersion-air roasting sample was higher,and the wavenumber of the CO adsorption peak appeared blue shift,which indicated that the positive metal content increased and the content of Pt2+in the Pt/TiO2-air 500℃ catalyst is more,which stabilized and increases the proportion of oxidized metals.To further investigate the influence of the electronic structure of the catalyst on the adsorption behavior of the reactants,the results found that the Pt2+species played a role in adsorbing and activating the C-O bond of octanol,thereby promoting the reaction.Secondly,aiming at the regulation of support coordination structure,anatase TiO2 with adjustable proportions of exposed(001)crystal plane was prepared by hydrothermal synthesis method to support Pt by impregnation-calcination method,the obtained catalysts were named Pt/TiO2-001 air 500℃,Pt/TiO2-101-001 air 500℃ and Pt/TiO2-101 air 500℃ according to(001)crystal plane exposure ratio from high to low,to explore the influence of the synergism of support coordination structure and metallic electronic structure on the catalytic behaviour in selective octanol oxidation.The results showed that the apparent activation energy of Pt/TiO2-001 air 500℃ is 27.64 kJ/mol,which is obviously lower than 40.83 kJ/mol of Pt/TiO2-101 air 500℃,which indicated that the former has higher catalytic intrinsic activity.In addition,under the same conversion,the selectivity of Pt/TiO2-001 air 500℃ to acid is 20%higher than that of Pt/TiO2-101 air 500℃.Furthermore,XRD,HR-TEM,Raman,CO2-FTIR,CO-FTIR,XPS,octanol-FTIR,and octanal-FTIR revealed the effect of the support coordination structure on the directional activation of reactants and the induction of metal electronic structure.The analysis of support structure showed that the O2c-Tisc-O2c coordination unsaturated sites on the TiO2(001)plane dissociate the C=O of the aldehyde group in the form of bidentate,thereby promoting the oxidation of octanal to octanoic acid.Analysis of the electronic structure of the catalyst showed that during air roasting,strong electron interaction(EMSI)occurs between Pt and TiO2,electrons are transferred from Pt to TiO2,and the coordinate unsaturated O2c sites on the(001)plane have a better ability to combine the Pt species,the EMSI effect is enhanced,resulting in an decrease in the content of positive valence metals,and the formation of Ti5c-O2c-Pt2+ active sites on the interface between Pt and TiO2.To further explore the influence of the catalyst structure on the adsorption behavior of reactants and intermediate products through in-situ FTIR technology,the results showed that the Ti5c-O2c-Pt2+ active site plays a role in adsorbing and activating the C-O bond of octanol and the C=O bond of octanal,thereby promoting the reaction. 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