n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.0...n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极具有优异的稳定性和PEC水氧化活性,具有相对低的OER起始电位(相对于可逆氢电极电势(RHE)仅为0.938 V),并且在1.23 V vs.RHE电位时具有较高的光电流密度(33.1 m A·cm^(-2)),显著优于Ni/p^(+)n-Si光阳极。工作证明了Fe在Ni层的掺杂会在Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si界面处产生较大的能带弯曲,促进界面电荷分离。此外,Co的加入会产生丰富的Ni^(3+)和氧空位(Ov),作为活性位点可以加速OER动力学过程,协同促进PEC过程中的水氧化的活性。令人鼓舞的是,通过将Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极连接到廉价的硅太阳能电池上,所制备的集成光伏/PEC(PV/PEC)器件实现了无偏压下高达12.0%的太阳制氢能量转换效率。这项工作提供了一种简单的方法来设计高效、稳定的n-Si基光阳极,并对其构效关系有了深刻的理解;这种方法制备的材料在集成低成本PV/PEC器件用于无辅助太阳能驱动水分解方面具有巨大的潜力。展开更多
The linear motor applied in electromagnetic emission system uses a closed loop position control strategy,which needs a set of position measurement system with high reliability,high resolution and integration to achiev...The linear motor applied in electromagnetic emission system uses a closed loop position control strategy,which needs a set of position measurement system with high reliability,high resolution and integration to achieve real-time acquisition and analysis of position signals.The existing position controller is based on the simple logic chip design without memory function,and does not have the storage analysis and preprocessing function to position signals.Therefore,the system has insufficient scalability,low integration and reliability.Aiming at the improvement of the existing position measurement system,an intelligent position measurement system integrating the functions of position signals acquisition,processing and uploading,data storage and analysis is proposed in this paper,and its working principle and system composition are discussed in detail.The position,speed and acceleration obtained on the electromagnetic emission platform are in good agreement with the expected value of the system.As results,the feasibility and accuracy of the improved integrated intelligent position measurement system are verified,and the control performance of the system is also satisfied well,which can be good guidance and reference for subsequent engineering practice.展开更多
基金supported by the Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China(51888103)Shaohua Shen is grateful to the National Natural Science Foundation of China(52225606)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Youth Innovation Team of Shaanxi Universities。
文摘n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极具有优异的稳定性和PEC水氧化活性,具有相对低的OER起始电位(相对于可逆氢电极电势(RHE)仅为0.938 V),并且在1.23 V vs.RHE电位时具有较高的光电流密度(33.1 m A·cm^(-2)),显著优于Ni/p^(+)n-Si光阳极。工作证明了Fe在Ni层的掺杂会在Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si界面处产生较大的能带弯曲,促进界面电荷分离。此外,Co的加入会产生丰富的Ni^(3+)和氧空位(Ov),作为活性位点可以加速OER动力学过程,协同促进PEC过程中的水氧化的活性。令人鼓舞的是,通过将Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极连接到廉价的硅太阳能电池上,所制备的集成光伏/PEC(PV/PEC)器件实现了无偏压下高达12.0%的太阳制氢能量转换效率。这项工作提供了一种简单的方法来设计高效、稳定的n-Si基光阳极,并对其构效关系有了深刻的理解;这种方法制备的材料在集成低成本PV/PEC器件用于无辅助太阳能驱动水分解方面具有巨大的潜力。
基金This work was supported in part by the National Natural Science Foundation of China(NSFC)under Grant 51507182 and 51477178.
文摘The linear motor applied in electromagnetic emission system uses a closed loop position control strategy,which needs a set of position measurement system with high reliability,high resolution and integration to achieve real-time acquisition and analysis of position signals.The existing position controller is based on the simple logic chip design without memory function,and does not have the storage analysis and preprocessing function to position signals.Therefore,the system has insufficient scalability,low integration and reliability.Aiming at the improvement of the existing position measurement system,an intelligent position measurement system integrating the functions of position signals acquisition,processing and uploading,data storage and analysis is proposed in this paper,and its working principle and system composition are discussed in detail.The position,speed and acceleration obtained on the electromagnetic emission platform are in good agreement with the expected value of the system.As results,the feasibility and accuracy of the improved integrated intelligent position measurement system are verified,and the control performance of the system is also satisfied well,which can be good guidance and reference for subsequent engineering practice.
