Ultralow operating voltage for energy conversion performance in Hf_(1-x)Zr_(x)O_(2) thin films  

作　　者：Ying Hou Baoyuan Wang Zhen Luo Xinzhe Du Zijian Wang Yi Fang Xiaoguang Li 

机构地区：[1]School of Physics,East China University of Science and Technology,Shanghai,200237,China [2]State Key Laboratory of Powder Metallurgy,Central South University,Changsha,410083,China [3]Hefei National Research Center for Physical Sciences at the Microscale,Department of Physics and CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics,University of Science and Technology of China,Hefei,230026,China

出　　处：《Journal of Materiomics》2024年第6期1206-1213,共8页无机材料学学报（英文）

基　　金：The authors acknowledge the financial support by National Natural Science Foundation of China(Grant Nos.52272109,91963116,and U21A2066);National Key Research and Development Program of China(2022YFB3807604);Natural Science Foundation of Shanghai(Grant No.19ZR1411900);State Key Laboratory of Powder Metallurgy,Central South University,Changsha,China.

摘　　要：Emerging ferroelectric and antiferroelectric HfO_(2)-based thin films are attractive candidates for energy conversion and storage applications. In this work, the polar phase transformation between tetragonal and orthorhombic phases associated with ferroelectric or antiferroelectric behaviors is utilized to manipulate the electrocaloric cooling and energy storage performances in Zr-doped, woken up HfO_(2) ultrathin films. A giant electrocaloric temperature change of up to 11.85 K in Hf_(0.5)Zr_(0.5)O_(2) with the morphotropic phase boundary (MPB) state and a high energy storage density of 39.34 J/cm^(3) in the tetragonal phase-dominant Hf0.25Zr0.75O2 system are obtained. More interestingly, contrary to overdoping and excessive electric fields, an appropriate Zr concentration of 0.5 and an applicable driving field of 1.91 MV/cm are desired for the electrocaloric effect, resulting in an ultralow operating voltage as low as 1.3 V in this 6.8 nm thick Hf_(0.5)Zr_(0.5)O_(2) film. These findings illustrate that the structural design strategy is a visible method for achieving optimal energy-related behaviors and highlight the great possibilities for building future energy-related devices.

关 键 词：HfO_(2)-based films Morphotropic phase boundary state Electrocaloric cooling Energy storage 

分 类 号：O48[理学—固体物理]