以三聚氰胺苯甲酸盐为碳源和氮源、以三聚氰胺磷钼酸盐为钼源、磷源和氮源,采用程序升温的方法制备了系列N,P掺杂型C@Mo_2C催化剂。采用XRD、SEM、TEM和XPS等对催化剂的结构、形貌和表面特性进行了表征,研究了三聚氰胺苯甲酸盐中n(三聚...以三聚氰胺苯甲酸盐为碳源和氮源、以三聚氰胺磷钼酸盐为钼源、磷源和氮源,采用程序升温的方法制备了系列N,P掺杂型C@Mo_2C催化剂。采用XRD、SEM、TEM和XPS等对催化剂的结构、形貌和表面特性进行了表征,研究了三聚氰胺苯甲酸盐中n(三聚氰胺)/n(苯甲酸)、前驱体中n(C)/n(Mo)等因素对所制备催化剂的结构及其在二氧化碳加氢反应中催化性能的影响。在反应温度为220℃、反应压力为3.0 MPa、空速为3 600 m L/(g·h)的条件下,在N,P掺杂型C@Mo_2C的催化作用下,CO_2转化率可以达到12.2%,此时产物中CH_3OH的选择性达到52.2%。展开更多
The development of high-energy-density Li-ion batteries is hindered by the irreversible capacity loss during the initial charge-discharge process.Therefore,pre-lithiation technology has emerged in the past few decades...The development of high-energy-density Li-ion batteries is hindered by the irreversible capacity loss during the initial charge-discharge process.Therefore,pre-lithiation technology has emerged in the past few decades as a powerful method to supplement the undesired lithium loss,thereby maximizing the energy utilization of LIBs and extending their cycle life.Lithium oxalate(Li_(2)C_(2)O_(4)),with a high lithium content and excellent air stability,has been considered one of the most promising materials for lithium compensation.However,the sluggish electrochemical decomposition kinetics of the material severely hinders its further commercial application.Here,we introduce a recrystallization strategy combined with atomic Ni catalysts to modulate the mass transport and decomposition reaction kinetics.The decomposition potential of Li_(2)C_(2)O_(4)is significantly decreased from~4.90V to~4.30V with a high compatibility with the current battery systems.In compared to the bare NCM//Li cell,the Ni/N-rGO and Li_(2)C_(2)O_(4)composite(Ni-LCO)modified cell releases an extra capacity of~11.7%.Moreover,this ratio can be magnified in the NCM//SiOx full cell,resulting in a 30.4%higher reversible capacity.Overall,this work brings the catalytic paradigm into the pre-lithiation technology,which opens another window for the development of high-energy-density battery systems.展开更多
The novel copper?complex with salicylaldehyde benzoylhydrazone and pyridine ligands, Cu(C14H10N2O2)(C5H5N), has been synthesized and characterized by elemental analysis, IR and thermal analysis. The crystal structure ...The novel copper?complex with salicylaldehyde benzoylhydrazone and pyridine ligands, Cu(C14H10N2O2)(C5H5N), has been synthesized and characterized by elemental analysis, IR and thermal analysis. The crystal structure of the title complex has been determined by single crystal X ray diffraction techniques. The crystal belongs to monoclinic with space group P21/c. The cell parameters are: a=1.6362(9)nm, b=1.7140(9)nm, c=1.2255(7)nm, β=105.168(9)°, V=3.317(3)nm3, Z=8, Dc=1.525g·cm-3, μ(MoKα)=1.334mm-1, F(000)=1560. The structure wasrefined to final R1=0.0376, wR2=0.0909. The copper?ion lies in a distorted square planar environment composed of two oxygen atoms, one nitrogen atom of tridentate acyhydrazone Schiff base ligand and one nitrogen atom of the pyridine ligand. CCDC: 193111.展开更多
文摘以三聚氰胺苯甲酸盐为碳源和氮源、以三聚氰胺磷钼酸盐为钼源、磷源和氮源,采用程序升温的方法制备了系列N,P掺杂型C@Mo_2C催化剂。采用XRD、SEM、TEM和XPS等对催化剂的结构、形貌和表面特性进行了表征,研究了三聚氰胺苯甲酸盐中n(三聚氰胺)/n(苯甲酸)、前驱体中n(C)/n(Mo)等因素对所制备催化剂的结构及其在二氧化碳加氢反应中催化性能的影响。在反应温度为220℃、反应压力为3.0 MPa、空速为3 600 m L/(g·h)的条件下,在N,P掺杂型C@Mo_2C的催化作用下,CO_2转化率可以达到12.2%,此时产物中CH_3OH的选择性达到52.2%。
基金supported by National Natural Science Foundation of China(Grant No.52002094)Guangdong Basic and Applied Basic Research Foundation(Grant No.2019A1515110756)+2 种基金Shenzhen Science and Technology Program(Grant No.JCYJ20210324121411031,JSGG202108021253804014,RCBS20210706092218040)the Shenzhen Steady Support Plan(GXWD20221030205923001,GXWD20201230155427003-20200824103000001)School Research Startup Expenses of Harbin Institute of Technology(Shenzhen)(Grant No.DD29100027,DD45001022).
文摘The development of high-energy-density Li-ion batteries is hindered by the irreversible capacity loss during the initial charge-discharge process.Therefore,pre-lithiation technology has emerged in the past few decades as a powerful method to supplement the undesired lithium loss,thereby maximizing the energy utilization of LIBs and extending their cycle life.Lithium oxalate(Li_(2)C_(2)O_(4)),with a high lithium content and excellent air stability,has been considered one of the most promising materials for lithium compensation.However,the sluggish electrochemical decomposition kinetics of the material severely hinders its further commercial application.Here,we introduce a recrystallization strategy combined with atomic Ni catalysts to modulate the mass transport and decomposition reaction kinetics.The decomposition potential of Li_(2)C_(2)O_(4)is significantly decreased from~4.90V to~4.30V with a high compatibility with the current battery systems.In compared to the bare NCM//Li cell,the Ni/N-rGO and Li_(2)C_(2)O_(4)composite(Ni-LCO)modified cell releases an extra capacity of~11.7%.Moreover,this ratio can be magnified in the NCM//SiOx full cell,resulting in a 30.4%higher reversible capacity.Overall,this work brings the catalytic paradigm into the pre-lithiation technology,which opens another window for the development of high-energy-density battery systems.
文摘The novel copper?complex with salicylaldehyde benzoylhydrazone and pyridine ligands, Cu(C14H10N2O2)(C5H5N), has been synthesized and characterized by elemental analysis, IR and thermal analysis. The crystal structure of the title complex has been determined by single crystal X ray diffraction techniques. The crystal belongs to monoclinic with space group P21/c. The cell parameters are: a=1.6362(9)nm, b=1.7140(9)nm, c=1.2255(7)nm, β=105.168(9)°, V=3.317(3)nm3, Z=8, Dc=1.525g·cm-3, μ(MoKα)=1.334mm-1, F(000)=1560. The structure wasrefined to final R1=0.0376, wR2=0.0909. The copper?ion lies in a distorted square planar environment composed of two oxygen atoms, one nitrogen atom of tridentate acyhydrazone Schiff base ligand and one nitrogen atom of the pyridine ligand. CCDC: 193111.
文摘采用真空浸渍法制备炭基固体碱催化剂K2O/C,并在超声波辅助条件下,利用制备的K2O/C催化纤维低聚糖与油酸甲酯制备纤维低聚糖脂肪酸酯表面活性剂。选取L9(34)正交试验确定制备K2O/C催化剂的最佳条件为:炭基载体平均孔径为2.87 nm,K2CO3与炭基载体的质量比值为0.5,真空浸渍后,450℃下煅烧2 h。考察了超声波辅助下超声波时间、超声波频率、反应温度、反应时间和催化剂用量对产品得率的影响。研究发现:在20 k Hz,150 W超声功率下,将物质的量之比为2∶1的油酸甲酯和纤维低聚糖(水溶液)超声波作用15 min,形成均一稳定的乳化体系,真空条件下,移除体系中的水分后,加入占总物料量5%的K2O/C催化剂,125℃下反应2 h,纤维低聚糖脂肪酸酯的最高得率为85.6%,其酯化度为18.8%,亲水亲油平衡值(HLB)为9.89,表面张力为32.1 m N/m,乳化力为28.1%,硬水稳定性4级。