The CuO/CeO_(2) composites with strong metal-support interaction were synthesised,which can efficiently electroreduct CO_(2)to C(2)H_(4).The Faradaic efficiency(FE)of C_(2)H_(4) could reach 50.5%with a current density...The CuO/CeO_(2) composites with strong metal-support interaction were synthesised,which can efficiently electroreduct CO_(2)to C(2)H_(4).The Faradaic efficiency(FE)of C_(2)H_(4) could reach 50.5%with a current density of 18 mA cm^(-2).The strong metal-support interaction could not only enhance the adsorption and activation of CO_(2),but also can stablize the CuO.展开更多
Introducing vacancy defects and unique morphology is an effective strategy to improve the catalytic performance of transition metal compounds.However,precisely controlling the amount of vacancy defects remains challen...Introducing vacancy defects and unique morphology is an effective strategy to improve the catalytic performance of transition metal compounds.However,precisely controlling the amount of vacancy defects remains challenging.Here,we propose a facile and efficient hydrothermal accompanying an annealing method to synthesize a series of Mn-doped CoO nanomaterials with controllable oxygen vacancies and unique morphology.The oxygen vacancies amount can be precisely controlled by adjusting the Mndoping content and is positively correlated with catalytic performance.It was found that the oxygen vacancies amount can reach up to 38.2%over the Mn-doped CoO nanomaterials,resulting in ultra-high hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalytic activity(HER:25.6 and 37 m V at 10 m A cm^(-2);OER:301 and 322 m V at 50 m A cm^(-2))under both basic and acidic conditions,while reaching 10 m A cm^(-2) for an ultra-low cell voltage of only 1.52 V,which exceeds that of Pt/C/RuO_(2) and all reported non-noble metal oxide catalysts.The DFT calculations reveal oxygen vacancies can optimize H*and HOO*intermediates adsorption free energy,thus improving the HER and OER performance.Interestingly,the Mn-doped CoO with rich oxygen vacancies exhibits excellent antibacterial properties in vitro of biomedicine.This work provides new ideas and methods for the rational design and precise control of vacancy defects in transition metal compounds and explores their potential application value in electrochemical water splitting and biomedical fields.展开更多
由于其丰度高、电化学稳定性强,MoS_(2)被认为是一种极具前途的电催化剂.然而,其导电性差和活性低,因此催化性能受到限制.此外,MoS_(2)无法满足工业化大规模应用的要求.本工作中,为了获得具有S空位缺陷的P掺杂MoS_(2)催化剂,我们在室温...由于其丰度高、电化学稳定性强,MoS_(2)被认为是一种极具前途的电催化剂.然而,其导电性差和活性低,因此催化性能受到限制.此外,MoS_(2)无法满足工业化大规模应用的要求.本工作中,为了获得具有S空位缺陷的P掺杂MoS_(2)催化剂,我们在室温下通过固相离子交换将P插入到MoS_(2)基体中.当P掺杂量为11.4 wt%时为最佳,所制备的催化剂具有优异的电催化析氢(HER)和析氧(OER)性能.碱性条件下,在10 mA cm^(-2)电流密度下对应的过电位分别为93和316 mV,这些数值超过了先前报道的大多数二硫化钼基材料的过电位.理论计算和实验结果都表明,MoS_(2)基面上形成的掺杂P活性中心及由P掺杂引起的S空位缺陷的协同作用增强了催化剂的本征电子电导率和电催化活性.密度泛函理论计算表明,与原始的MoS_(2)相比,P优化了MoS_(2)氢吸附自由能,从而显著提高了掺杂后催化剂对HER的固有活性.P掺杂MoS_(2)对OER的催化活性增强归因于掺杂P促进羟基和含氧中间体的吸附及反应能垒的降低.本研究提出了一种全新、环保、便捷的固相离子交换法来提高二维过渡金属硫族化合物在大规模应用中的电催化能力.展开更多
Inspired by the cockroach’s use of a pitch-roll mode traverses through narrow obstacles,we improve the RHex-style robot by adding two sprawl joints to adjust the body posture,and propose a novel pitch-roll approach t...Inspired by the cockroach’s use of a pitch-roll mode traverses through narrow obstacles,we improve the RHex-style robot by adding two sprawl joints to adjust the body posture,and propose a novel pitch-roll approach that enables an RHex-style robot to traverse through two cylindrical obstacles with a spacing of 90 mm,about 54%body width.First,the robot can pitch up against the obstacle on the one side by the cooperation of its rear and middle legs.Then,the robot rotates one side rear leg to kick the ground fast,meanwhile the sprawl joint on the other side rotates inward to make the robot roll and fall forward.Finally,the robot can rotate the legs on the ground to move the body forward until it crosses the obstacles.In this article,both cylinder and rectangular columns are considered as the narrow obstacles for traversing.The experiments are demonstrated by using the proposed approach,and the results show that the robot can smoothly traverse through different narrow spaces.展开更多
RHex-style robots can perform manifold moving gaits in different applications,but they have always faced a challenge of climbing up high obstacles.In this paper,the bionics-based gait optimization in an RHex-style rob...RHex-style robots can perform manifold moving gaits in different applications,but they have always faced a challenge of climbing up high obstacles.In this paper,the bionics-based gait optimization in an RHex-style robot is proposed for climbing steps at different heights,which even enables the robot to climb up the step with 4.2 times of the leg length.First,a thoracic flexion is designed in the robot,and an algorithm of adjusting body inclination is proposed to perform the rising stage after placing front legs on top of step,which can be applied in different RHex-style robots with different sizes.Especially,when the thoracic flexion is implemented,the robot can climb the higher step with the proposed algorithm.Second,to climbing the higher steps,a claw-shape legs-based algorithm is proposed for robot reaching the higher step and climbing it up.During the vital rising stage,when the front legs of the robot have reached the top of the step,the robot can bend the front body downward with its thoracic flexion like a cockroach,and then lift the front and middle legs alternately to move COM up and forward onto the step.The simulation analysis is utilized to verify the feasibility of the proposed algorithms.Finally,the step-climbing experiments at different heights are performed in our robot to compare with the existing works.The results of simulations and experiments show the superiority of the proposed algorithms for the improved robot due to climbing up the higher steps.展开更多
基金supported by the National Key Research and Development Program of China(2017YFA0403102)National Natural Science Foundation of China(21573073,21733011)+1 种基金Beijing Municipal Science&Technology Commission(Z191100007219009)the Chinese Academy of Sciences(QYZDY-SSW-SLH013)。
文摘The CuO/CeO_(2) composites with strong metal-support interaction were synthesised,which can efficiently electroreduct CO_(2)to C(2)H_(4).The Faradaic efficiency(FE)of C_(2)H_(4) could reach 50.5%with a current density of 18 mA cm^(-2).The strong metal-support interaction could not only enhance the adsorption and activation of CO_(2),but also can stablize the CuO.
基金supported by the National Natural Science Foundation of China(52072196,52002199,52002200,52102106)the Major Basic Research Program of the Natural Science Foundation of Shandong Province(ZR2020ZD09)+1 种基金the Innovation and Technology Program of Shandong Province(2020KJA004)the Taishan Scholars Program of Shandong Province(ts201511034)。
文摘Introducing vacancy defects and unique morphology is an effective strategy to improve the catalytic performance of transition metal compounds.However,precisely controlling the amount of vacancy defects remains challenging.Here,we propose a facile and efficient hydrothermal accompanying an annealing method to synthesize a series of Mn-doped CoO nanomaterials with controllable oxygen vacancies and unique morphology.The oxygen vacancies amount can be precisely controlled by adjusting the Mndoping content and is positively correlated with catalytic performance.It was found that the oxygen vacancies amount can reach up to 38.2%over the Mn-doped CoO nanomaterials,resulting in ultra-high hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalytic activity(HER:25.6 and 37 m V at 10 m A cm^(-2);OER:301 and 322 m V at 50 m A cm^(-2))under both basic and acidic conditions,while reaching 10 m A cm^(-2) for an ultra-low cell voltage of only 1.52 V,which exceeds that of Pt/C/RuO_(2) and all reported non-noble metal oxide catalysts.The DFT calculations reveal oxygen vacancies can optimize H*and HOO*intermediates adsorption free energy,thus improving the HER and OER performance.Interestingly,the Mn-doped CoO with rich oxygen vacancies exhibits excellent antibacterial properties in vitro of biomedicine.This work provides new ideas and methods for the rational design and precise control of vacancy defects in transition metal compounds and explores their potential application value in electrochemical water splitting and biomedical fields.
基金supported by the National Natural Science Foundation of China(52072196)the Major Basic Research Program of the Natural Science Foundation of Shandong Province(ZR2020ZD09)。
文摘由于其丰度高、电化学稳定性强,MoS_(2)被认为是一种极具前途的电催化剂.然而,其导电性差和活性低,因此催化性能受到限制.此外,MoS_(2)无法满足工业化大规模应用的要求.本工作中,为了获得具有S空位缺陷的P掺杂MoS_(2)催化剂,我们在室温下通过固相离子交换将P插入到MoS_(2)基体中.当P掺杂量为11.4 wt%时为最佳,所制备的催化剂具有优异的电催化析氢(HER)和析氧(OER)性能.碱性条件下,在10 mA cm^(-2)电流密度下对应的过电位分别为93和316 mV,这些数值超过了先前报道的大多数二硫化钼基材料的过电位.理论计算和实验结果都表明,MoS_(2)基面上形成的掺杂P活性中心及由P掺杂引起的S空位缺陷的协同作用增强了催化剂的本征电子电导率和电催化活性.密度泛函理论计算表明,与原始的MoS_(2)相比,P优化了MoS_(2)氢吸附自由能,从而显著提高了掺杂后催化剂对HER的固有活性.P掺杂MoS_(2)对OER的催化活性增强归因于掺杂P促进羟基和含氧中间体的吸附及反应能垒的降低.本研究提出了一种全新、环保、便捷的固相离子交换法来提高二维过渡金属硫族化合物在大规模应用中的电催化能力.
基金This work was supported in part by the National Natural Science Foundation of China(No.51605393)China Postdoctoral Science Foundation(No.2018M633398)+1 种基金State Key Laboratory of Robotics and Systems(HIT)(SKLRS-2020-KF-13)Sichuan Science and Technology Program(2020YJ0035).
文摘Inspired by the cockroach’s use of a pitch-roll mode traverses through narrow obstacles,we improve the RHex-style robot by adding two sprawl joints to adjust the body posture,and propose a novel pitch-roll approach that enables an RHex-style robot to traverse through two cylindrical obstacles with a spacing of 90 mm,about 54%body width.First,the robot can pitch up against the obstacle on the one side by the cooperation of its rear and middle legs.Then,the robot rotates one side rear leg to kick the ground fast,meanwhile the sprawl joint on the other side rotates inward to make the robot roll and fall forward.Finally,the robot can rotate the legs on the ground to move the body forward until it crosses the obstacles.In this article,both cylinder and rectangular columns are considered as the narrow obstacles for traversing.The experiments are demonstrated by using the proposed approach,and the results show that the robot can smoothly traverse through different narrow spaces.
基金This work was supported in part by the National Natural Science Foundation of China(No.51605393)State Key Laboratory of Robotics and Systems(HIT)(SKLRS-2020-KF-13)Sichuan Science and Technology Program(2020YJ0035).
文摘RHex-style robots can perform manifold moving gaits in different applications,but they have always faced a challenge of climbing up high obstacles.In this paper,the bionics-based gait optimization in an RHex-style robot is proposed for climbing steps at different heights,which even enables the robot to climb up the step with 4.2 times of the leg length.First,a thoracic flexion is designed in the robot,and an algorithm of adjusting body inclination is proposed to perform the rising stage after placing front legs on top of step,which can be applied in different RHex-style robots with different sizes.Especially,when the thoracic flexion is implemented,the robot can climb the higher step with the proposed algorithm.Second,to climbing the higher steps,a claw-shape legs-based algorithm is proposed for robot reaching the higher step and climbing it up.During the vital rising stage,when the front legs of the robot have reached the top of the step,the robot can bend the front body downward with its thoracic flexion like a cockroach,and then lift the front and middle legs alternately to move COM up and forward onto the step.The simulation analysis is utilized to verify the feasibility of the proposed algorithms.Finally,the step-climbing experiments at different heights are performed in our robot to compare with the existing works.The results of simulations and experiments show the superiority of the proposed algorithms for the improved robot due to climbing up the higher steps.
