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YZ
Verified CAS / Academic Author5 Decoded Studies

Prof. YU Zhiyuan

Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), College of Environmental Science and Engineering, Hunan University

Co-Affiliations:Engineering Technology Center for Pollution Control of the Nonferrous Metal Industry, Ministry of Ecology and Environment, Hunan Research Academy of Environmental Sciences, Changsha 410004, China

Research Publications & English Decoded Briefs

Showing 5 publications
The Chinese Journal of Process Engineering2026DOI: 10.12034/j.issn.1009-606X.225191

Optimization Strategies for Thermal Transport Properties in p-Type Mg3Sb2-Based Thermoelectric Materials: A Review

Mg3Sb2-based materials, featuring a unique layered crystal structure, exhibit a favorable combination of low thermal conductivity, high Seebeck coefficient, and decent carrier mobility, establishing them among the most promising mid-temperature thermoelectric systems under active investigation. However, p-type Mg3Sb2 derivatives demonstrate a comparatively lower thermoelectric figure of merit (zT) compared to their n-type counterparts. Enhancing the zT performance of p-type Mg3Sb2 is therefore essential for the development of high-efficiency thermoelectric devices based on this material system. This review systematically summarizes the critical factors governing the thermal transport properties of p-type Mg3Sb2, including intrinsic characteristics such as chemical bonding and crystal structure, as well as extrinsic parameters such as carrier concentration, mobility, point defects, microstructure, and temperature dependence effects. Furthermore, it highlights recent advances in strategies designed to optimize thermal conductivity (κ) and improve zT, mainly including point defect engineering (such as Mg-site doping, Sb-site doping, dual-site co-doping, as well as doping-assisted composite modification), low-dimensional and nanostructural design, and advanced preparation technologies. Experimental studies demonstrate that these targeted strategies, particularly the synergistic introduction of multi-scale defects, can effectively suppress phonon propagation and significantly reduce lattice thermal conductivity (κL). Consequently, substantial improvements in the overall zT of p-type Mg3Sb2-based materials have been realized, providing a robust scientific and technical foundation for accelerating the practical application of Mg3Sb2-based thermoelectric devices.

Chinese Journal of Environmental Engineering2026DOI: 10.12030/j.cjee.202507094

Strength and Microstructural Characteristics of Sludge Solidified by Loess-Based Composite Solidifying Agent

To address land waste and poor bearing capacity from sludge landfill, this study developed a composite solidifying agent using loess, fly ash, desulfurized gypsum, and cement. Orthogonal experiments combined strength testing, SEM/XRD microanalysis, permeability and heavy metal leaching tests, and cost accounting. Results show that cement significantly enhances early and mid-term strength, while loess dominates later strength development. Optimal fly ash and desulfurized gypsum content is 12% each. The optimal mix ratio (loess:fly ash:desulfurized gypsum:cement:sludge) is 0.1:0.12:0.12:0.08:1. The solidified matrix forms dense structures via C-S-H gel and ettringite (Aft), effectively controlling heavy metal leaching at low cost. This work enables solid waste resource utilization and provides robust support for sludge solidification engineering.

Environmental Chemistry2026DOI: 10.7524/j.issn.0254-6108.2025022501

Comparison and Optimization of Pretreatment Methods for Emerging Contaminants and Application in Industrial Wastewater Samples

The pretreatment of trace emerging contaminants in environmental matrices is challenging due to diverse methods and uncertain applicability. This study compared solid-phase extraction (SPE) and liquid-liquid extraction (LLE) for extracting endocrine-disrupting compounds (EDCs), particularly phthalate esters (PAEs), using laboratory-spiked blank samples. LLE achieved satisfactory recoveries for PAEs at spike levels below 4 μg·L−1, enabling detection of five PAEs including diisodecyl phthalate (DIDP), with improved efficiency via repeated extraction. SPE offered lower detection and quantification limits, higher accuracy and sensitivity, and achieved high recoveries for 12 EDCs and 10 antibiotics at spike levels ≥0.2 μg·L−1, with detection limits as low as 0.1–6.4 ng·L−1. The developed SPE coupled with liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was applied to industrial wastewater samples. Across five industrial sectors (coatings, rubber, pharmaceuticals, inks, and materials technology), five antibiotics and ten EDCs were detected, with total concentrations ranging from 0.03–0.56 μg·L−1 and 0.07–1.91 μg·L−1, respectively. Sector-specific profiles emerged: rubber industry effluent was dominated by dibutyl phthalate (DBP) at 1.07 μg·L−1, while pharmaceutical effluent featured sulfamonomethoxine (SMM) at 0.34 μg·L−1. This systematic evaluation demonstrates that SPE-LC-Orbitrap MS is robust for complex matrices, providing a technical foundation for accurate quantification of emerging contaminants in industrial wastewater.

Journal of Environmental Engineering Technology2026DOI: 10.13205/j.hjgc.202606016

Mechanism of Desulfurization Pretreatment of Barium-Containing Waste Slag by Calcium Carbonate Precipitation Method

Barium slag, a solid waste from barium salt production, poses environmental risks due to high sulfur and soluble barium content. This study investigated the desulfurization of barium slag using sodium carbonate (Na2CO3) as a precipitating agent. The effects of reaction temperature, time, and Na2CO3 concentration on desulfurization efficiency were systematically evaluated. X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) were employed to analyze phase transformations and microstructural evolution. Results showed that desulfurization primarily proceeds via the reaction of ettringite (Ca6(Al(OH)6)2(SO4)3·26H2O) with Na2CO3, forming calcium carbonate (CaCO3) precipitates. However, the precipitated CaCO3 accumulates on ettringite surfaces, hindering further reaction. Under optimal conditions (60 °C, 5 h, 2 mol/L Na2CO3), the desulfurization efficiency reached 91.21%, reducing sulfur content in the slag to 0.27%, meeting the HJ 662—2013 standard for cement kiln co-processing. This work provides a mechanistic basis for efficient and environmentally sound treatment of barium slag, supporting its resource utilization in cement production.

SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3875-1

In-situ growth of ZnIn2S4 nanosheets on a Ti-based MOF to form a core-shell heterojunction for enhanced photocatalytic hydrogen evolution

Photocatalytic hydrogen evolution reaction (HER) from pure water is a promising strategy to address critical challenges in energy sustainability and environmental remediation. However, HER over single-component photocatalysts is intrinsically limited by inefficient carrier separation and relatively poor photostability. Forming abundant interfaces between two components is an effective approach for solving these issues. Herein, a series of hierarchical core-shell heterojunction photocatalysts, designated as F@Z-X, was rationally constructed by in situ growing ZnIn2S4 (ZIS) nanosheets on a Ti-based metal-organic framework (FIR-125), demonstrating remarkable structural stability. Due to the abundant intimate contact interfaces and well-matched band structure, the F@Z-X series exhibit enhanced HER performance. Among them, the optimized heterojunction [email protected] shows a photocatalytic hydrogen evolution rate of 3789.45 μmol g−1 h−1, which is about 4.4 and 264.4 times higher than that of pristine ZIS (859.57 μmol g−1 h−1) and FIR-125 (15.32 μmol g−1 h−1), respectively. Moreover, the photocatalyst manifests excellent reusability and durability, maintaining its performance over five consecutive cycles and sixteen hours of continuous reaction. The outstanding performance of [email protected] may be ascribed to an optimal balance among three fundamental photocatalytic processes: sufficient light absorption, exceptional carrier separation, and appropriate surface reaction. This work offers valuable insights into the rational design and controllable synthesis of novel heterojunction photocatalysts for efficient hydrogen evolution.

Prof. YU Zhiyuan | Publications & Academic Profile | SinoGreenTech | SinoGreenTech