The perovskite oxides were known as an oxygen anion intercalation electrode material for pseudocapacitance in 2014[1].Although this new energy storage mechanism is defined as oxygen anion intercalation,it differs fund...The perovskite oxides were known as an oxygen anion intercalation electrode material for pseudocapacitance in 2014[1].Although this new energy storage mechanism is defined as oxygen anion intercalation,it differs fundamentally from ion intercalation in batteries.As shown in Fig.1a,b,energy storage and release are mainly achieved through bulk redox reactions in the electrodes for batteries,controlled by bulk diffusion,demonstrating high energy and low power density[2].For pseudocapacitors,a type of supercapacitor,their electrochemical characteristics differ from those of double-layer capacitors,which only undergo physical reactions,and also differ from batteries,which undergo Faraday redox reactions in the bulk phase.Pseudocapacitance primarily relies on surface Faradaic reactions caused by charge transfer at or near the surface,without bulk diffusion control,enabling them to maintain impressive energy density while also exhibiting extremely fast reaction kinetics[3].Oxygen anion intercalation is a typical pseudocapacitive behavior.展开更多
Despite enormous efforts in actuators,most researches are only limited to various actuation behaviors and demonstrations of soft materials.It has not yet been reported to capture and monitor its movement status in an ...Despite enormous efforts in actuators,most researches are only limited to various actuation behaviors and demonstrations of soft materials.It has not yet been reported to capture and monitor its movement status in an invisible environment.Therefore,it is of great significance to develop a self-sensing and self-actuating dual-function hydrogel actuator system to realize real-time monitoring.Here,we report a bifunctional hydrogel system with self-actuating and self-monitoring abilities,which combines the functions of photothermal actuation and electrical resistance sensing into a single material.The bilayer tough conductive hydrogel synthesized by unconventional complementary concentration recombination and cryogenic freezing technique presents a dense conductive network and high-porosity structure,achieving high toughness at 190.3 kPa of tensile strength,high stretchability(164.3%strain),and the toughness dramatically(1,471.4 kJ·m^(−3)).The working mechanism of the monitoring and self-sensing system is accomplished through the integrated monitoring device of surface temperature–bending angle–electron current,to solve the problem of not apperceiving actuator motion state when encountering obstacles in an invisible environment.We demonstrated for the first time a photothermal actuator’s motion of a football player and goalkeeper to finish the penalty and a soft actuator hand,which can achieve the action of sticking to grab and release under photo-thermal actuation.When connected to the control closed circuit,the actuator realized closed-loop monitoring and sensing feedback.The development of bifunctional hydrogel systems may bring new opportunities and ideas in the fields of material science,circuit technology,sensors,and mechanical engineering.展开更多
Antibiotic pollution in aqueous solutions seriously endangers the natural environment and public health.In this work,Mo-doped transition metal FeCo–Se metal aerogels(MAs)were investigated as bifunctional catalysts fo...Antibiotic pollution in aqueous solutions seriously endangers the natural environment and public health.In this work,Mo-doped transition metal FeCo–Se metal aerogels(MAs)were investigated as bifunctional catalysts for the removal of sulfamethazine(SMT)in solution.The optimal Mo_(0.3)Fe_(1)Co_(3)–Se catalyst can remove 97.7% of SMT within 60 min(SMT content:10 mg/L,current intensity:10 mA/cm 2).The unique porous cross-linked structure of aerogel confered the catalyst sufficient active sites and efficient mass transfer channels.For the anode,Mo_(0.3)Fe_(1)Co_(3)–Se MAs exhibits superior oxygen evolution reaction(OER)property,with an overpotential of only 235 mV(10 mA/cm 2).Compared with Fe_(1)Co_(3) MAs or Mo_(0.3)Fe_(1)Co_(3) MAs,density functional theory(DFT)demonstrated that the better catalytic capacity of Mo_(0.3)Fe_(1)Co_(3)–Se MAs is attributed to the doping of Mo species and selenization lowers the energy barrier for the*OOH to O_(2) step in the OER process.Excellent OER perfor-mance ensures the self-oxygenation in this system,avoiding the addition of air or oxygen in the traditional electro-Fenton process.For the cathode,Mo doping can lead to the lattice contraction and metallic character of CoSe_(2),which is beneficial to accelerate electron transfer.The adjacent Co active sites effectively adsorb*OOH and inhibit the breakage of the O–O bond.Rotating ring disk electrode(RRDE)test indicated that Mo_(0.3)Fe_(1)Co_(3)–Se MAs has an excellent 2e^(-)ORR activity with H_(2)O_(2) selectivity up to 88%,and the generated H_(2)O_(2) is activated by the adjacent Fe site through heterogeneous Fenton process to generate⋅OH.展开更多
基金financially supported by the Guangdong Basic and Applied Basic Research Foundation(2022B1515120019)the Science and Technology Development Project of Guangdong Academy of Sciences(2022GDASZH-2022010109,2023GDASZH-2023030601)。
文摘The perovskite oxides were known as an oxygen anion intercalation electrode material for pseudocapacitance in 2014[1].Although this new energy storage mechanism is defined as oxygen anion intercalation,it differs fundamentally from ion intercalation in batteries.As shown in Fig.1a,b,energy storage and release are mainly achieved through bulk redox reactions in the electrodes for batteries,controlled by bulk diffusion,demonstrating high energy and low power density[2].For pseudocapacitors,a type of supercapacitor,their electrochemical characteristics differ from those of double-layer capacitors,which only undergo physical reactions,and also differ from batteries,which undergo Faraday redox reactions in the bulk phase.Pseudocapacitance primarily relies on surface Faradaic reactions caused by charge transfer at or near the surface,without bulk diffusion control,enabling them to maintain impressive energy density while also exhibiting extremely fast reaction kinetics[3].Oxygen anion intercalation is a typical pseudocapacitive behavior.
基金the Science Foundation of China University of Petroleum,Beijing(No.2462019BJRC007)the National Natural Science Foundation of China(No.22178384).
文摘Despite enormous efforts in actuators,most researches are only limited to various actuation behaviors and demonstrations of soft materials.It has not yet been reported to capture and monitor its movement status in an invisible environment.Therefore,it is of great significance to develop a self-sensing and self-actuating dual-function hydrogel actuator system to realize real-time monitoring.Here,we report a bifunctional hydrogel system with self-actuating and self-monitoring abilities,which combines the functions of photothermal actuation and electrical resistance sensing into a single material.The bilayer tough conductive hydrogel synthesized by unconventional complementary concentration recombination and cryogenic freezing technique presents a dense conductive network and high-porosity structure,achieving high toughness at 190.3 kPa of tensile strength,high stretchability(164.3%strain),and the toughness dramatically(1,471.4 kJ·m^(−3)).The working mechanism of the monitoring and self-sensing system is accomplished through the integrated monitoring device of surface temperature–bending angle–electron current,to solve the problem of not apperceiving actuator motion state when encountering obstacles in an invisible environment.We demonstrated for the first time a photothermal actuator’s motion of a football player and goalkeeper to finish the penalty and a soft actuator hand,which can achieve the action of sticking to grab and release under photo-thermal actuation.When connected to the control closed circuit,the actuator realized closed-loop monitoring and sensing feedback.The development of bifunctional hydrogel systems may bring new opportunities and ideas in the fields of material science,circuit technology,sensors,and mechanical engineering.
基金Thanks for the support of the National Natural Science Foundation of China(No.21776308)in this work.
文摘Antibiotic pollution in aqueous solutions seriously endangers the natural environment and public health.In this work,Mo-doped transition metal FeCo–Se metal aerogels(MAs)were investigated as bifunctional catalysts for the removal of sulfamethazine(SMT)in solution.The optimal Mo_(0.3)Fe_(1)Co_(3)–Se catalyst can remove 97.7% of SMT within 60 min(SMT content:10 mg/L,current intensity:10 mA/cm 2).The unique porous cross-linked structure of aerogel confered the catalyst sufficient active sites and efficient mass transfer channels.For the anode,Mo_(0.3)Fe_(1)Co_(3)–Se MAs exhibits superior oxygen evolution reaction(OER)property,with an overpotential of only 235 mV(10 mA/cm 2).Compared with Fe_(1)Co_(3) MAs or Mo_(0.3)Fe_(1)Co_(3) MAs,density functional theory(DFT)demonstrated that the better catalytic capacity of Mo_(0.3)Fe_(1)Co_(3)–Se MAs is attributed to the doping of Mo species and selenization lowers the energy barrier for the*OOH to O_(2) step in the OER process.Excellent OER perfor-mance ensures the self-oxygenation in this system,avoiding the addition of air or oxygen in the traditional electro-Fenton process.For the cathode,Mo doping can lead to the lattice contraction and metallic character of CoSe_(2),which is beneficial to accelerate electron transfer.The adjacent Co active sites effectively adsorb*OOH and inhibit the breakage of the O–O bond.Rotating ring disk electrode(RRDE)test indicated that Mo_(0.3)Fe_(1)Co_(3)–Se MAs has an excellent 2e^(-)ORR activity with H_(2)O_(2) selectivity up to 88%,and the generated H_(2)O_(2) is activated by the adjacent Fe site through heterogeneous Fenton process to generate⋅OH.
