本论文基于传统聚合物基炭材料合成原理,通过选择合适结构的前驱体分子,在聚合过程中分子水平锚定Co原子,同时引入TiO_(2)纳米颗粒,再经高温焙烧后制得一种双金属氮氧化物(Co_(m)Ti_(n)O_(x)N_(y))-Co单原子(Co-NC)复合催化剂。该催化...本论文基于传统聚合物基炭材料合成原理,通过选择合适结构的前驱体分子,在聚合过程中分子水平锚定Co原子,同时引入TiO_(2)纳米颗粒,再经高温焙烧后制得一种双金属氮氧化物(Co_(m)Ti_(n)O_(x)N_(y))-Co单原子(Co-NC)复合催化剂。该催化剂在酸性(E_(onset)=0.755 V vs.RHE,0.5 mol/LH_(2)SO_(4);0.760 V vs.RHE,0.1mol/LHClO_(4))、中性(E_(onset)=0.787 V vs.RHE,0.1 mol/L PBS)、碱性(E_(onset)=0.880 V vs.RHE,0.1 mol/L KOH)电解液中的氧气还原(ORR)性能(pH=0-13)均优于纯氮杂碳纳米管、氮杂碳纳米管负载的金属氮氧化物和Co单原子催化剂,表明,Co_(m)Ti_(n)O_(x)N_(y)与Co单原子的协同效应使得复合催化剂具有更好的ORR活性,同时复合催化剂的稳定性和选择性显著优于商品Pt/C催化剂。这为开发高性能低成本氧气还原电催化剂提供了新的思路。展开更多
Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile...Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal oxide.Herein,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2)) is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2) from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2) did not possess.Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2) catalyst.As for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2) generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene.This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.展开更多
文摘本论文基于传统聚合物基炭材料合成原理,通过选择合适结构的前驱体分子,在聚合过程中分子水平锚定Co原子,同时引入TiO_(2)纳米颗粒,再经高温焙烧后制得一种双金属氮氧化物(Co_(m)Ti_(n)O_(x)N_(y))-Co单原子(Co-NC)复合催化剂。该催化剂在酸性(E_(onset)=0.755 V vs.RHE,0.5 mol/LH_(2)SO_(4);0.760 V vs.RHE,0.1mol/LHClO_(4))、中性(E_(onset)=0.787 V vs.RHE,0.1 mol/L PBS)、碱性(E_(onset)=0.880 V vs.RHE,0.1 mol/L KOH)电解液中的氧气还原(ORR)性能(pH=0-13)均优于纯氮杂碳纳米管、氮杂碳纳米管负载的金属氮氧化物和Co单原子催化剂,表明,Co_(m)Ti_(n)O_(x)N_(y)与Co单原子的协同效应使得复合催化剂具有更好的ORR活性,同时复合催化剂的稳定性和选择性显著优于商品Pt/C催化剂。这为开发高性能低成本氧气还原电催化剂提供了新的思路。
基金financially supported by the National Natural Science Foundation of China(21935001,22175012,22005022)the S&T Program of Hebei(21344601D)+2 种基金the Beijing Natural Science Foundation(2214062)the Program for Changjiang Scholars and Innovation Research Team in the University(No.IRT1205)the Fundamental Research Funds for the Central Universities。
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supported by the National Natural Science Foundation of China(21673215,21473169,51402283)the Fundamental Research Funds for the Central Universities,China(WK2060030029,WK6030000015)the Max-Planck Partner Group~~
文摘Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal oxide.Herein,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2)) is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2) from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2) did not possess.Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2) catalyst.As for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2) generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene.This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.
