高熵二硼化物纳米颗粒的组分设计与催化降解抗生素研究

Composition engineering of high-entropy diboride nanoparticles for efficient catalytic degradation of antibiotics

开发高熵硼化物材料的功能特性对于拓宽其在极端环境中的潜在应用至关重要.为此,本文通过调控材料的组分开发出具有高效催化性能的高熵二硼化物(HEB_(2))纳米颗粒:首先基于对HEB_(2)的尺寸差异因子、混合焓以及体系自蔓延燃烧模式的理论分析,我们采用一种简便、快速、低成本的燃烧合成方法合成了6种不同组分的HEB_(2)纳米颗粒;然后,通过对材料的组分进行调控实现了HEB_(2)纳米颗粒活化过硫酸盐降解抗生素的高效催化能力(四环素的最高去除效率可达93.5%).不同吸附位点的吸附能和差分电荷密度的第一性原理计算结果进一步证实了HEB_(2)优异的催化性能主要归因于Ti组元,而非高熵效应.此外,基于检测到的活性氧和计算的反应能垒,我们提出了HEB_(2)活化过硫酸盐降解抗生素的潜在催化机理.本研究不仅为HEB_(2)高效催化降解抗生素的组分设计提供了理论依据,而且显示出HEB_(2)在去除自然水体中新污染物方面的潜在应用前景.

Exploiting functional characteristics of highentropy boride materials is critical for extending their potential applications in harsh environments.Herein we develop high-entropy diboride(HEB_(2))nanoparticles with efficient catalytic performance by engineering their compositions.Based on the theoretical analysis of the lattice size difference and mixing enthalpy of HEB_(2) and the self-propagating combustion mode of the system,six different compositional HEB_(2) nanoparticles are synthesized via a facile,rapid,and low-cost combustion synthesis method.By engineering their compositions,we achieve the efficient catalytic ability of HEB_(2) nanoparticles in persulfate activation towards antibiotics removal,namely the highest tetracycline removal efficiency of 93.5%.Further investigations of the adsorption energy and the charge density difference of various adsorption sites via density functional theory confirm that the outstanding catalytic ability mainly originates from the Ti constituent rather than the high-entropy effect.In addition,a potential catalytic mechanism of HEB_(2) towards persulfate activation for antibiotics degradation is proposed based on the detected reactive oxygen species and the computational reaction energy barrier.This study not only provides theoretical basis for their component design in the efficient catalytic degradation of antibiotics,but also shows a promising application of HEB_(2) for removal of emerging contaminants from environmental water matrices.