The band structure of a heterojunction significantly affects its photocharge separation efficiency.Designing heterojunctions with suitable band structures is very important for photocatalytic applications.Herein,we de...The band structure of a heterojunction significantly affects its photocharge separation efficiency.Designing heterojunctions with suitable band structures is very important for photocatalytic applications.Herein,we demonstrate that Bi_(5)Ti_(3)FeO_(15)/BiOCl(BTF/BOC),a type-I heterostructure,could change the flow direction of photocharges via ferroelectric polarization.展开更多
Metal carbides are an emerging class of electrode materials for various electrochemical applications.Herein,we have synthesized the molybdenum carbide(Mo_(2)C)hexagons via a template assisted method.Subsequently,the M...Metal carbides are an emerging class of electrode materials for various electrochemical applications.Herein,we have synthesized the molybdenum carbide(Mo_(2)C)hexagons via a template assisted method.Subsequently,the Mo_(2)C hexagons were integrated with functionalized carbon nanofiber(f-CNF)via the ultra-sonication method.The prepared Mo_(2)C and Mo_(2)C/f-CNF composites were analyzed using different techniques such as XRD,RAMAN,HR-TEM,and ESCA.展开更多
As a promising hydrogen evolution reaction(HER)electrocatalyst,molybdenum carbide materials have attracted great attention owing to their Pt-like electronic structure.The morphology control of Mo_(2)C usually involves...As a promising hydrogen evolution reaction(HER)electrocatalyst,molybdenum carbide materials have attracted great attention owing to their Pt-like electronic structure.The morphology control of Mo_(2)C usually involves complicated procedures,and porous structures are desirable for electrocatalytic applications.Herein,we present a facile acid-directed synthesis strategy forβ-Mo_(2)C nanoparticles embedded in a nitrogen doped carbon matrix(β-Mo_(2)C/NC)with controllable morphologies through heat treatment of Mo-melamine complexes for electrocatalytic HER applications.It is found that the applied acid can effectively tune the morphology of Mo-melamine complexes,and thus the finalβ-Mo_(2)C/NC materials.With oxalic acid,the as-preparedβ-Mo_(2)C/NC materials possess a porous structure and high surface area(23.3 m^(2)g^(-1)),leading to distinguished electrocatalytic HER activities in both acidic and alkaline media,requiring low overpotentials of 152 and 135 mV vs.reversible hydrogen electrode(RHE)to reach a current density of-10 mA cm^(-2),with a Tafel slope of 58 and 56 mV dec^(-1),respectively.The synthetic route proposed in this work may offer a new thinking for the morphology-controllable synthesis of transition metal carbide materials for heterogeneous(electro)catalysis applications.展开更多
基金support from the National Natural Science Foundation of China(Grant No.51972029).
文摘The band structure of a heterojunction significantly affects its photocharge separation efficiency.Designing heterojunctions with suitable band structures is very important for photocatalytic applications.Herein,we demonstrate that Bi_(5)Ti_(3)FeO_(15)/BiOCl(BTF/BOC),a type-I heterostructure,could change the flow direction of photocharges via ferroelectric polarization.
文摘Metal carbides are an emerging class of electrode materials for various electrochemical applications.Herein,we have synthesized the molybdenum carbide(Mo_(2)C)hexagons via a template assisted method.Subsequently,the Mo_(2)C hexagons were integrated with functionalized carbon nanofiber(f-CNF)via the ultra-sonication method.The prepared Mo_(2)C and Mo_(2)C/f-CNF composites were analyzed using different techniques such as XRD,RAMAN,HR-TEM,and ESCA.
基金support from the National Natural Science Foundation of China(21671047 and 21871065)the Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(no.2018B030322001).
文摘As a promising hydrogen evolution reaction(HER)electrocatalyst,molybdenum carbide materials have attracted great attention owing to their Pt-like electronic structure.The morphology control of Mo_(2)C usually involves complicated procedures,and porous structures are desirable for electrocatalytic applications.Herein,we present a facile acid-directed synthesis strategy forβ-Mo_(2)C nanoparticles embedded in a nitrogen doped carbon matrix(β-Mo_(2)C/NC)with controllable morphologies through heat treatment of Mo-melamine complexes for electrocatalytic HER applications.It is found that the applied acid can effectively tune the morphology of Mo-melamine complexes,and thus the finalβ-Mo_(2)C/NC materials.With oxalic acid,the as-preparedβ-Mo_(2)C/NC materials possess a porous structure and high surface area(23.3 m^(2)g^(-1)),leading to distinguished electrocatalytic HER activities in both acidic and alkaline media,requiring low overpotentials of 152 and 135 mV vs.reversible hydrogen electrode(RHE)to reach a current density of-10 mA cm^(-2),with a Tafel slope of 58 and 56 mV dec^(-1),respectively.The synthetic route proposed in this work may offer a new thinking for the morphology-controllable synthesis of transition metal carbide materials for heterogeneous(electro)catalysis applications.
