Piezocatalytic hydrogen evolution has emerged as a promising direction for the collection and utilization of mechanical energy and the efficient generation of sustainable energy throughout the day.Hexagonal CdS,as an ...Piezocatalytic hydrogen evolution has emerged as a promising direction for the collection and utilization of mechanical energy and the efficient generation of sustainable energy throughout the day.Hexagonal CdS,as an established semiconductor photocatalyst,has been widely investigated for splitting water into H_(2),while its piezocatalytic performance has attracted less attention,and the relationship between the structure and piezocatalytic activity remains unclear.Herein,two types of CdS nanostructures,namely CdS nanorods and CdS nanospheres,were prepared to probe the above‐mentioned issues.Under ultrasonic vibration,the CdS nanorods afforded a superior piezocatalytic H_(2) evolution rate of 157μmol g^(−1)h^(−1)in the absence of any co‐catalyst,which is nearly 2.8 times that of the CdS nanospheres.The higher piezocatalytic activity of the CdS nanorods is derived from their larger piezoelectric coefficient and stronger mechanical energy harvesting capability,affording a greater piezoelectric potential and more efficient separation and transfer of intrinsic charge carriers,as elucidated through piezoelectric response force microscopy,finite element method,and piezoelectrochemical tests.This study provides a new concept for the design of efficient piezocatalytic materials for converting mechanical energy into sustainable energy via microstructure regulation.展开更多
Direct Z-scheme CdO-CdS 1-dimensional nanorod arrays were constructed through a facile and simple hydrothermal process. The structure, morphology, photoelectrochemical properties and H2 evolution activity of this cata...Direct Z-scheme CdO-CdS 1-dimensional nanorod arrays were constructed through a facile and simple hydrothermal process. The structure, morphology, photoelectrochemical properties and H2 evolution activity of this catalyst were investigated systematically. The morphology of the obtained nanorod is a regular hexagonal prism with 100-200 nm in diameter. The calcination temperature and time were optimized carefully to achieve the highest photoelectrochemical performance. The as-fabricated hybrid system achieved a photocurrent density up to 6.5 mA/cm2 and H2 evolution rate of 240 μmol·cm-2·h-1 at 0 V vs. Ag/AgCl, which is about 2-fold higher than that of the bare CdS nanorod arrays. The PEC performance exceeds those previously reported similar systems. A direct Z-scheme photocatalytic mechanism was proposed based on the structure and photoelectrochemical performance characterization results, which can well explain the high separation efficiency of photoinduced carriers and the excellent redox ability.展开更多
文摘Piezocatalytic hydrogen evolution has emerged as a promising direction for the collection and utilization of mechanical energy and the efficient generation of sustainable energy throughout the day.Hexagonal CdS,as an established semiconductor photocatalyst,has been widely investigated for splitting water into H_(2),while its piezocatalytic performance has attracted less attention,and the relationship between the structure and piezocatalytic activity remains unclear.Herein,two types of CdS nanostructures,namely CdS nanorods and CdS nanospheres,were prepared to probe the above‐mentioned issues.Under ultrasonic vibration,the CdS nanorods afforded a superior piezocatalytic H_(2) evolution rate of 157μmol g^(−1)h^(−1)in the absence of any co‐catalyst,which is nearly 2.8 times that of the CdS nanospheres.The higher piezocatalytic activity of the CdS nanorods is derived from their larger piezoelectric coefficient and stronger mechanical energy harvesting capability,affording a greater piezoelectric potential and more efficient separation and transfer of intrinsic charge carriers,as elucidated through piezoelectric response force microscopy,finite element method,and piezoelectrochemical tests.This study provides a new concept for the design of efficient piezocatalytic materials for converting mechanical energy into sustainable energy via microstructure regulation.
基金supported by the National Natural Science Foundation of China(No.U1632273,No.21673214,No.U1732272,and No.U1832165)
文摘Direct Z-scheme CdO-CdS 1-dimensional nanorod arrays were constructed through a facile and simple hydrothermal process. The structure, morphology, photoelectrochemical properties and H2 evolution activity of this catalyst were investigated systematically. The morphology of the obtained nanorod is a regular hexagonal prism with 100-200 nm in diameter. The calcination temperature and time were optimized carefully to achieve the highest photoelectrochemical performance. The as-fabricated hybrid system achieved a photocurrent density up to 6.5 mA/cm2 and H2 evolution rate of 240 μmol·cm-2·h-1 at 0 V vs. Ag/AgCl, which is about 2-fold higher than that of the bare CdS nanorod arrays. The PEC performance exceeds those previously reported similar systems. A direct Z-scheme photocatalytic mechanism was proposed based on the structure and photoelectrochemical performance characterization results, which can well explain the high separation efficiency of photoinduced carriers and the excellent redox ability.
