中国科学技术大学肖翀团队近日实现了在Bridgman生长过程中利用Soret效应合成高熵梯度晶体。相关论文于2025年7月30日发表在《美国化学会杂志》上。

功能梯度材料表现出成分或结构的梯度变化，为不同的应用领域创造了新的功能材料。包含多个元素的高熵晶体有望实现连续的元素调节，促进功能梯度材料的实现。然而，人们对高熵梯度晶体的本征性质的研究仍然有限，高熵梯度晶体的合成由于其强烈的固有无序性而具有挑战性。

研究组提出了一种利用Bridgman生长中的Soret效应合成高熵梯度晶体的一般方法。在AgSbPbSnGeTe₅多晶的基础上，研究组整合了梯度晶体和高熵晶体的概念，最终通过晶体生长过程中的Soret效应首次成功合成了高熵梯度晶体。Bridgman方法中的宏观温度梯度驱动致密、完整的毫米尺寸单晶的生长，而微观温度梯度诱导Soret效应，导致高熵铸锭中的成分梯度。为了证明其热电效用，在673 K时，在高熵梯度晶体中实现了高ZT ~1.44。该工作建立了利用Bridgman方法中的Soret效应设计高熵梯度晶体的一般范例，为新兴功能需求提供了一种新的人造材料，并为大尺寸高熵单晶的合成提供了重要的启示。

附：英文原文

Title: Synthesis of High-Entropy Gradient Crystals via the Soret Effect during Bridgman Growth

Author: Kai Li, Liang Sun, Qingqing Liu, Ni Ma, Wei Bai, Chong Xiao, Yi Xie

Issue&Volume: July 30, 2025

Abstract: Functionally gradient materials exhibit compositional or structural gradient changes, creating new functional materials for diverse application domains. High-entropy crystals containing multiple elements hold the promise of continuous elemental regulation, facilitating the realization of functionally gradient materials. However, intrinsic property studies of high-entropy gradient crystals remain limited, and the synthesis of high-entropy gradient crystals is challenging due to the strong inherent disorder. Herein, we propose a general approach to synthesize high-entropy gradient crystals via the Soret effect in Bridgman growth. Based on the polycrystalline AgSbPbSnGeTe5, we integrate the concepts of gradient crystals and high-entropy crystals, culminating in the first successful synthesis of high-entropy gradient crystals via the Soret effect during crystal growth. The macroscopic temperature gradient in the Bridgman method drives the growth of dense, intact millimeter-sized single crystals, while the microscopic temperature gradient induces the Soret effect, leading to a compositional gradient in the high-entropy ingot. As a demonstration of its thermoelectric utility, an intrinsically high ZT ～1.44 at 673 K was achieved in high-entropy gradient crystals. This work establishes a general paradigm for designing high-entropy gradient crystals via the Soret effect in the Bridgman method, providing a new man-made material for emerging functional needs and shedding useful light on the synthesis of large-sized high-entropy single crystal.

DOI: 10.1021/jacs.5c09415

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c09415