Yuqiao Zhang 교수

Two-dimensional electron systems have attracted attention as thermoelectric materials, which can directly convert waste heat into electricity. It has been theoretically predicted that thermoelectric power factor can be largely enhanced when the two-dimensional electron layer is far narrower than the de Broglie wavelength. Although many studies have been made, the effectiveness has not been experimentally clarified thus far. Here we experimentally clarify that an enhanced two-dimensionality is ef

Abstract Various CuS nanostructures, including nanoflowers, doughnut‐shaped nanospheres, dense nanospheres, and mixtures of nanoneedles, nanoparticles, and nanoplates, were synthesized from different copper and sulfur sources by a solvothermal method. The formation mechanisms along with photocatalytic properties for the degradation of rhodamine B (RhB) under visible‐light irradiation were investigated in this study. The experimental results indicate that when the sulfur source is fixed at CS(NH

The rise of recycled integrated circuits (ICs) in the critical infrastructures causes a major concern to the government and industry because these chips exhibit lower performance and have shorter remaining useful life. The detection of these ICs becomes extremely challenging when they are in the supply chain. It is necessary to power up a chip at a distributor's site to measure different electrical parameters for verifying whether it is used before. However, this can be challenging, as many of t

A high <italic>ZT</italic> of 0.11 at room temperature was realized in layered cobalt oxide by substitution of heavy atomic mass Ba.

Thermoelectric technology has emerged as a prominent area of research in the past few decades for harnessing waste heat and improving the efficiency of next-generation renewable energy technologies. There has been rapid progress in the development of high-performance thermoelectric materials, as measured by the dimensionless figure of merit (<i>ZT</i> = <i>S</i>² · <i>σ</i> · <i>κ</i>^-1). Several heavy-metal-based thermoelectric materials with commercial-level performance (

Here, we present a thermoelectric phase diagram for the SrTi1−xNbxO3 (0.05 ≤ x ≤ 1) solid solution system, which we derived from the characterization of epitaxial films. We observed two thermoelectric phase boundaries in the system, which originate from the step-like decrease in carrier effective mass at x ∼ 0.3 and from a local minimum in carrier relaxation time at x ∼ 0.5. The origins of these phase boundaries are considered to be related to isovalent/heterovalent B-site substitution: paraboli

Due to the outsourcing of semiconductor design and manufacturing, a number of threats have emerged in recent years, and they are overproduction of integrated circuits (ICs), illegal sale of defective ICs, and piracy of intellectual properties (IPs). Logic locking is one method to enable trust in this complex IC design and manufacturing processes, where a design is obfuscated by inserting a lock to modify the underlying functionality so that an adversary cannot make a chip to function properly. A

Thermoelectric energy conversion technology has attracted attention as an energy harvesting technology that converts waste heat into electricity by means of the Seebeck effect. Oxide-based thermoelectric materials that show a high figure of merit are promising because of their good chemical and thermal stability as well as their harmless nature compared to chalcogenide-based state-of-the-art thermoelectric materials. Although several high-<i>ZT</i> thermoelectric oxides (<i>ZT</i> > 1) have been

A novel Bi₂S₃/CuS hybrid photocatalyst with a 3D hierarchical configuration was synthesized through an <italic>in situ</italic> solution-based cation exchange reaction that leads to obvious enhancements in charge separation and photocatalytic performance.

Abstract Oxide-based thermoelectric materials that show a high figure of merit are promising because of their good chemical and thermal stabilities and their relative harmlessness compared with chalcogenide-based state-of-the-art thermoelectric materials. Although several high- ZT thermoelectric oxides ( ZT &gt; 1) have been reported thus far, their reliability levels are low due to the lack of careful observations of their stabilities at elevated temperatures. Herein, we review the epitaxial fi

Controllable synthesis of uniformly disk-shaped CuS nanostructures with a narrow size distribution was realized by a low-temperature (150 °C) solvothermal process using polyvinyl pyrrolidone (PVP) as the surfactant.

Abstract Electron‐doped SrTiO 3 has been attracting attention as oxide thermoelectric materials, which can convert wasted heat into electricity. The power factor of the electron‐doped SrTiO 3 , including SrTiO 3 ‐LaTiO 3 and SrTiO 3 ‐SrNbO 3 solid solutions, has been clarified. However, their thermal conductivity ( κ ) has not been clearly identified thus far. Only a high κ (&gt;12 W m −1 K −1 ) has been assumed from the electron contribution based on Wiedemann–Franz law. Here, we show that the

Cavitation commonly occurs in the hydraulic machineries like inducers. Cavitation happening in the cryogens is sophisticated due to their complicated thermodynamic properties. Computational fluid dynamics could provide relatively precise prediction for water. However, existing computational fluid dynamics methods may fail to simulate the cryogens cavitation precisely. This study presents a computational fluid dynamics simulation of four major cavitation models in both the liquid nitrogen and the

Systematic clarification of thermoelectric properties of a solid-solution system is essentially important, especially if the materials have different crystal and electronic structures. Here, we report the thermoelectric phase diagram of the full-range Sr1 − xLaxTiO3 solid solutions composed of a band insulator SrTiO3 (cubic perovskite) and a Mott insulator LaTiO3 (distorted perovskite), which shows the room temperature thermoelectric power factor changing pattern with the La substitution (x) in

This perspective defines and explores an innovative waste heat harvesting strategy, thermoelectrocatalysis (TECatal), emphasizing materials design and potential applications in clean energy, environmental, and biomedical technologies.