Volume 5, Issue 4 (2025) – 35 articles
Cover Picture: Since the discovery of ferroelectricity in Si-doped HfO2 in 2011, HfO2-based materials have attracted extensive interest from researchers. Their various advantages provide a broad research prospect in the field of ferroelectric materials and devices. Researchers have conducted effective studies on the origin of ferroelectricity, the wake-up effect, the fatigue effect, and the potential for device applications. These studies contribute to a better understanding of the properties and applications of HfO2-based materials. This article provides a comprehensive review of the origin and influencing factors of ferroelectricity in HfO2, advantages in material applications, and limitations in applications from multiple perspectives. It also introduces the currently mature methods for preparing HfO2-based ferroelectric materials and cutting-edge applications in different device fields. Finally, the future development prospects of HfO2-based materials are also discussed.
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Back Cover Picture: Photothermoelectric (PTE) detectors hold immense potential for converting incident light signals into electrical signals, finding applications in sensing, astronomy, night vision, and communication. However, their widespread adoption is hindered by issues such as slow response times, low responsivity, and poor stability. In this study, a high-performance self-powered PTE detector based on the Ag2Se nanorods (NRs) and multi-walled carbon nanotubes (MWCNTs) is reported for the first time. The findings reveal that the electrical conductivity of the film increases with the addition of MWCNTs, albeit at the expense of the Seebeck coefficient. Notably, the film containing 0.5 wt% MWCNTs exhibited a superior power factor (303.22 μW·m-1·K-2) at 300 K. Owing to the high PTE performance, the photosensitive properties are characterized in an ultra-broadband range from the violet(405 nm) to infrared (2,500 nm) wavelengths, featuring rapid response time (1.4 s) and substantial output voltage(6.83 mV). Furthermore, the device demonstrated remarkable stability, with only a 3.4% decrease in output voltage after three months of air exposure and negligible changes in thirty cycles. Thus, the proposed device presents a novel strategy for developing PTE detectors characterized by broadband coverage, fast response times, and exceptional stability.
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