A novel cocatalyst,i.e.metallic nickel nanoparticles encapsulated in few-layer graphene(Ni@C),is obtained by carbonization of metal–organic frameworks(MOF)and leaching treatment of hydrochloric acid.It is selected as...A novel cocatalyst,i.e.metallic nickel nanoparticles encapsulated in few-layer graphene(Ni@C),is obtained by carbonization of metal–organic frameworks(MOF)and leaching treatment of hydrochloric acid.It is selected as the cocatalyst for CdS nanosheets,forming CdS-Ni@C nanocomposites.It remarkably improves the photocatalytic activities of CdS nanosheets due to the synergistic effect of Ni nanoparticles and graphene layers.In addition,the Ni nanoparticles encapsulated by graphene layers effectively isolate Ni from the ambient,which avoids contamination and curbs corrosion.The larger work function of Ni@C and outstanding conductivity of graphene promote the electron transfer from CdS to Ni@C,suppressing the recombination of photogenerated carriers and facilitating the separation of photogenerated electronhole pairs.This strategy by adopting this novel cocatalyst provides a new solution to the improvement of the photocatalytic hydrogen production.展开更多
Olefin epoxidation is a fundamental reaction in organic chemistry.Herein,a novel magnetic core-shell Fe_(3)O_(4)@Cu_(3)(BTC)_(2) metal-organic framework(MOF)heterogeneous catalyst was synthesized for the use in olefin...Olefin epoxidation is a fundamental reaction in organic chemistry.Herein,a novel magnetic core-shell Fe_(3)O_(4)@Cu_(3)(BTC)_(2) metal-organic framework(MOF)heterogeneous catalyst was synthesized for the use in olefin epoxidation.Additionally,the size selectivity of the Fe_(3)O_(4)@Cu_(3)(BTC)_(2) catalyst in olefin epoxidation was investigated.Scanning electron microscopy(SEM)and transmission electron microscopy(TEM)results indicated that Fe_(3)O_(4)@Cu_(3)(BTC)_(2) presented a microsphere morphology,and Cu_(3)(BTC)_(2) MOFs were well dispersed on the Fe_(3)O_(4)(PAA)surface after 10 cycles of the synthesis process.The synthesized magnetic core-shell Fe_(3)O_(4)@Cu_(3)(BTC)_(2) heterogeneous catalyst could facilitate efficient aerobic olefin epoxidation.Furthermore,the catalyst was used in the aerobic oxidation of alcohols and was found to exhibit excellent activity for primary alcohols.展开更多
Modulation of metal sites coordination can significantly refine the electronic architecture of catalysts,thereby improving their catalytic performance.This work successfully developed a core–shell Co@N-doped porous c...Modulation of metal sites coordination can significantly refine the electronic architecture of catalysts,thereby improving their catalytic performance.This work successfully developed a core–shell Co@N-doped porous carbon(Co@NC)catalyst by pyrolyzing the COF/MOF(IISERP-COF3/ZIF-67)composite in an inert atmosphere.The Co@NC catalyst exhibited impressive oxygen evolution reaction(OER)performance,with a small overpotential of 304 mV and a modest Tafel slope of 88.6 mV·dec^(−1) in a 1 M KOH,alongside remarkable stability,maintaining 98.5%of its activity over 13 h.The role of IISERP-COF3 was pivotal in preventing Co atom aggregation during the ZIF-67 pyrolysis,which facilitated the creation of mesopores for enhanced mass transport and conductivity.Moreover,it effectively modulated the Co-N coordination to fine-tune the electronic structure,thereby optimizing the catalyst's capacity for adsorption of intermediates and boosting its intrinsic activity.Density functional theory(DFT)studies corroborate that the exceptional OER efficiency of Co@NC can be linked to the enhanced Co-N coordination,optimizing the localized electronic structure at the Co active sites.This study not only proposes an innovative approach for optimizing COF/MOF as effective electrocatalysts but also clears the path for the emergence of affordable,high-performance alternatives to precious metal-based catalysts,marking a significant advancement in sustainable energy technologies.展开更多
Designing a heterojunction photocatalyst to improve the separation efficiency of photogenerated electrons and holes is of great significance to improve the hydrogen production efficiency.In this work,we report a ratio...Designing a heterojunction photocatalyst to improve the separation efficiency of photogenerated electrons and holes is of great significance to improve the hydrogen production efficiency.In this work,we report a rational design to grow ZnIN_(2)S_(4)on Mo-MOF-derived N-doped C-coated MoO_(2)(MOZIS),and it has excellent photocatalytic hydrogen production with triethanolamine(TEOA)as sacrificial agent.N-doped C improves the electron transport efficiency between MoO_(2)and ZnIN_(2)S_(4)·The systematic study shows that MOZIS has good properties to promote the effective separation and transfer of photocatalytic charges,which is attributed to the tight contact interface and good energy band structure between MoO_(2)and ZnlN_(2)S_(4).The optimized nanocomposites have a high hydrogen production efficiency of 10.89 mmol·g^(-1)(4 h)under visible light.MOF-derived N-doped C-coated MoO_(2)is an effective strategy to improve the photocatalytic hydrogen production efficiency of ZnIN_(2)S_(4).展开更多
基金Financially supported by the National Key Research and Development Program of China(No.2018YFB1502001)the National Natural Science Foundation of China(Nos.51872220,21871217,51961135303,51932007,U1905215 and U1705251)。
文摘A novel cocatalyst,i.e.metallic nickel nanoparticles encapsulated in few-layer graphene(Ni@C),is obtained by carbonization of metal–organic frameworks(MOF)and leaching treatment of hydrochloric acid.It is selected as the cocatalyst for CdS nanosheets,forming CdS-Ni@C nanocomposites.It remarkably improves the photocatalytic activities of CdS nanosheets due to the synergistic effect of Ni nanoparticles and graphene layers.In addition,the Ni nanoparticles encapsulated by graphene layers effectively isolate Ni from the ambient,which avoids contamination and curbs corrosion.The larger work function of Ni@C and outstanding conductivity of graphene promote the electron transfer from CdS to Ni@C,suppressing the recombination of photogenerated carriers and facilitating the separation of photogenerated electronhole pairs.This strategy by adopting this novel cocatalyst provides a new solution to the improvement of the photocatalytic hydrogen production.
基金supported by the Research Foundation of Hebei Agriculture University(China)for Talented Scholars(No.YJ201815)the Basic Scientific Research Project of Scientific Colleges and Universities in Hebei Province,China(No.KY2022017).
文摘Olefin epoxidation is a fundamental reaction in organic chemistry.Herein,a novel magnetic core-shell Fe_(3)O_(4)@Cu_(3)(BTC)_(2) metal-organic framework(MOF)heterogeneous catalyst was synthesized for the use in olefin epoxidation.Additionally,the size selectivity of the Fe_(3)O_(4)@Cu_(3)(BTC)_(2) catalyst in olefin epoxidation was investigated.Scanning electron microscopy(SEM)and transmission electron microscopy(TEM)results indicated that Fe_(3)O_(4)@Cu_(3)(BTC)_(2) presented a microsphere morphology,and Cu_(3)(BTC)_(2) MOFs were well dispersed on the Fe_(3)O_(4)(PAA)surface after 10 cycles of the synthesis process.The synthesized magnetic core-shell Fe_(3)O_(4)@Cu_(3)(BTC)_(2) heterogeneous catalyst could facilitate efficient aerobic olefin epoxidation.Furthermore,the catalyst was used in the aerobic oxidation of alcohols and was found to exhibit excellent activity for primary alcohols.
基金This work is supported by the National Natural Science Foundation of China (Nos.21133001 and 21303004),and the National Basic Research Program of China (Nos.2013CB932601 and 2014CB239303).
基金supported by the Platform of Science and Technology and Talent Team Plan of Guizhou province(No.GCC[2023]007)the National Natural Science Foundation of China(No.52062003).
文摘Modulation of metal sites coordination can significantly refine the electronic architecture of catalysts,thereby improving their catalytic performance.This work successfully developed a core–shell Co@N-doped porous carbon(Co@NC)catalyst by pyrolyzing the COF/MOF(IISERP-COF3/ZIF-67)composite in an inert atmosphere.The Co@NC catalyst exhibited impressive oxygen evolution reaction(OER)performance,with a small overpotential of 304 mV and a modest Tafel slope of 88.6 mV·dec^(−1) in a 1 M KOH,alongside remarkable stability,maintaining 98.5%of its activity over 13 h.The role of IISERP-COF3 was pivotal in preventing Co atom aggregation during the ZIF-67 pyrolysis,which facilitated the creation of mesopores for enhanced mass transport and conductivity.Moreover,it effectively modulated the Co-N coordination to fine-tune the electronic structure,thereby optimizing the catalyst's capacity for adsorption of intermediates and boosting its intrinsic activity.Density functional theory(DFT)studies corroborate that the exceptional OER efficiency of Co@NC can be linked to the enhanced Co-N coordination,optimizing the localized electronic structure at the Co active sites.This study not only proposes an innovative approach for optimizing COF/MOF as effective electrocatalysts but also clears the path for the emergence of affordable,high-performance alternatives to precious metal-based catalysts,marking a significant advancement in sustainable energy technologies.
基金financially supported by the Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology),Ministry of Education(No.JKF21-08)the Open Project of Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education(No.BWPU2021KF05)+3 种基金the National Natural Science Foundation of China(No.62104003)the Natural Science Foundation of Anhui Province(No.1908085QB75)Anhui Provincial Scientific and Technological Major Project(No.18030801109)the Opening Project of Engineering Technology Research Center of Anhui Education Department for Energy Saving and Pollutant Control in metallurgical process(No.GKF20-7)。
文摘Designing a heterojunction photocatalyst to improve the separation efficiency of photogenerated electrons and holes is of great significance to improve the hydrogen production efficiency.In this work,we report a rational design to grow ZnIN_(2)S_(4)on Mo-MOF-derived N-doped C-coated MoO_(2)(MOZIS),and it has excellent photocatalytic hydrogen production with triethanolamine(TEOA)as sacrificial agent.N-doped C improves the electron transport efficiency between MoO_(2)and ZnIN_(2)S_(4)·The systematic study shows that MOZIS has good properties to promote the effective separation and transfer of photocatalytic charges,which is attributed to the tight contact interface and good energy band structure between MoO_(2)and ZnlN_(2)S_(4).The optimized nanocomposites have a high hydrogen production efficiency of 10.89 mmol·g^(-1)(4 h)under visible light.MOF-derived N-doped C-coated MoO_(2)is an effective strategy to improve the photocatalytic hydrogen production efficiency of ZnIN_(2)S_(4).
