Journal of Cleaner Production
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2018
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IF 5.651
Yaocong Han,Xuemin Cui,Xuesen Lv,Kaituo Wang
Electrolytic manganese dioxide residue (EMDR) is a type of industrial solid waste that contains many soluble heavy metal ions . To reduce the hazard to environment, EMDR was proposed as raw material to fabricate phosphoric-acid-activated geopolymers in the present work. Relevant characteristics of these materials such as the compressive strength , bulk density, crystalline components, microstructure, leaching characteristic, high temperature resistance and corrosion resistance were investigated in this work. The results showed that EMDR was highly reactive with phosphoric acid and could be cured to form geopolymer gel materials with compressive strength up to 96.3 MPa after curing for 2 days at 80 °C with river sand added as an aggregate. Based on the analysis of X-ray diffraction and microstructure, the high compressive strength was due to the amorphous reaction products of phosphoric acid and magnetite in EMDR. The results of the leaching test of the geopolymer samples from EMDR showed that the manganese stabilization efficiency was 95.4%, and other measured elemental concentrations were all within the limits of Integrated Wastewater Discharge Standard in China when the CaO to wet EMDR ratio was 0.10. In addition, the geopolymers from EMDR showed good resistance to high temperature and aggressive environment except strong acid. Therefore, the results obtained in this study reveal that this method for the fabrication of geopolymers is a promising way to recycle EMDR and other iron-rich industrial solid wastes.
研究领域:
材料科学
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环境工程
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废物管理
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DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
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2025
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IF 13.1
Jiaxi Mao,Suxi Wang,Wentao Jia,Yi Liu,Shikun Chen,Yajun Zhang,Dongming Yan
The integration of mechanical robustness and ionic conductivity within cementitious materials represents a promising strategy toward multifunctional structural electrolytes for energy‐storage‐integrated construction systems. In this study, alkali‐activated metakaolin (MK) geopolymers were modified with different sodium salts (Na 2 SO 4 , NaCl, and NaOH) to elucidate the correlation between gel structure evolution, ion transport behavior, and electrochemical performance. Results showed that the incorporation of sodium salts significantly enhanced the ionic conductivity and capacitive performance of the geopolymer electrolytes. The Na 2 SO 4 ‐modified sample (MK‐S) exhibited the highest ionic conductivity of 33.22 mS cm -1 and an areal capacitance of 603.93 mF cm -2 , corresponding to a 4.5‐fold increase over unmodified MK. This improvement is attributed to the synergistic effect of increased mobile Na + concentration and optimized pore connectivity induced by SO 4 2- coordination. These findings demonstrate a viable route toward durable structural solid electrolytes for next‐generation energy‐storage‐integrated building materials.
研究领域:
材料科学
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储能
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土木工程
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电化学
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2026
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IF 8.9
Fei Wan,Zhengyang Zhou,Jijun Miao,Yanchun Liu,Chao Feng,Sergei Leonovich
Traditional epoxy resin (EP) adhesives are indispensable in modern engineering, yet their inherent trade-off between cross-linking density and fracture toughness, coupled with catastrophic interfacial degradation under extreme hygrothermal and high-temperature environments, severely limits their advanced applications. Herein, we propose a tailored "organic-inorganic topological bridging" strategy to construct a robust, highly cross-linked interpenetrating polymer network using core-shell functionalized green geopolymers (GP). By covalently grafting bi-functional silanes (KH550 and KH560) onto the SiO₄/AlO₄ inorganic frameworks, the incompatibility between polar GP and the epoxy matrix was effectively mitigated. At an optimized loading of 0.75 wt%, the KH560-GP/EP composite exhibited a 158% increase in fracture toughness (K IC = 3.1 MPa·m 1/2) and a 176% enhancement in tensile toughness. Furthermore, the hierarchical hybrid architecture improved the resistance of the adhesive to water, salt solution, acid, alkali, salt spray, and aviation kerosene. After thermal aging at 250 °C for 200 h, the optimized KH560-GP/EP adhesive retained a residual lap shear strength of 10.2 MPa when tested at room temperature, indicating improved resistance to irreversible thermal-aging-induced interfacial degradation.
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高影响因子
Journal of Cleaner Production
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2023
·
IF 11.1
Rongrong Zhang,Feng Li,Siqi Zhou,Yue Hou
Volcanic ash has several negative impacts on the environment and can be used in massive to synthesize geopolymers , which are considered quasi-brittle. Carbon nanofibers (CNFs) can reinforce the geopolymers, and the dispersion of CNFs directly determines the reinforcement effect. However, the dispersion of CNFs in alkali solutions is challenging. In this paper, the effect of surfactant type, dosage, and ultrasonic time on CNFs dispersion in aqueous and alkali solutions was investigated by the quantitive method of microscopic image processing to determine the preferred dispersion scheme. Zeta potential tests and visual observation were used to analyze the mechanism and stability. Based on this, volcanic ash-based geopolymer nanocomposites with 0.1 wt% contents of CNFs were synthesized. The mechanical properties were tested, and the microstructure was characterized using Scanning Electron Microscope coupled with Energy Dispersive Spectroscopy and Mercury Intrusion Porosimetry . The results showed that methylcellulose (MC), polycarboxylate superplasticizer (PC), and polyvinylpyrrolidone (PVP) could disperse CNFs in aqueous, but evident aggregations can be observed in the alkali solution. PC performed better than MC and PVP in alkali solutions, with 4.83% aggregation area of the whole image, 86% of 0–100 μm 2 aggregations, and an average aggregation area of 87 μm 2 , beneficial from the comb-like structures. Dispersed CNFs can improve the 28-d flexural and compressive strength of the resulting geopolymer nanocomposite by 23% and 16%, respectively, and refine the pore structure through filling, bridging, and nucleation effects, decreasing the average pore size and porosity by 33% and 15%. This paper will contribute to the resourceful use of volcanic ash to reduce pollution and the higher reinforcement of CNFs in alkali-activated geopolymers.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2023
·Vol. 30
·期 16
·47025-47037
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IF 5.8
Wang Tianyu,Yang Lang,Rao Feng,Jiang Kaixi,Byrynnai Choduraa
Adding organics in the process of geopolymer synthesis can combine the functional groups of organics with the three-dimensional structure of geopolymer, thus changing the properties of geopolymer such as compressive strength, flexural strength, and acid resistance. In this work, excellent mechanical properties and acid resistance of metakaolin-blast furnance slag (Mk-BFS)-based geopolymer were synthesized by the incorporation of chitosan. The formation of sodium-alumino-silicate-hydrate (N-A-S–H) gel and calium-alumino-silicate-hydrate (C-A-S–H) gel in geopolymerization were characterized by 29 Si nuclear magnetic resonance (NMR). At 5% of chitosan, the compressive strength of Mk-BFS-based geopolymer could reach to 33.7 MPa. The results could be ascribed to that chitosan reacts with geopolymer to generate new C-O-Si structure meanwhile adhesion produced by the combination of positively charged cations and negatively charged ions makes the structure of geopolymer denser. After 7 days of sulfuric acid immersion, the reduction of compressive strength is less than 3 MPa, demonstrating its great acid resistance. The acid resistance of Mk-BFS-based geopolymer could attribute to that the free amino groups in chitosan preferentially react with acid solution and weakened the erosion of sulfuric acid. This study optimizes the compressive strength and acid resistance of geopolymer by adding appropriate amount of chitosan.
研究领域:
材料科学
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硅酸盐化学
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无机非金属材料
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功能复合材料
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建筑材料
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2014
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IF 2.265
Xiaolu Guo,Wenpei Hu,Huisheng Shi
Nano-modified composite geopolymers were successfully prepared from municipal solid waste incineration fly ash (MSWIFA) and class C fly ash (CFA). The results indicate that both nano-SiO 2 and nano-γ-Al 2 O 3 have a good modification effect on geopolymer, of which nano-SiO 2 has a better performance than nano-γ-Al 2 O 3 . The optimum content of nano-SiO 2 and nano-γ-Al 2 O 3 are 1.5% and 2.0%, respectively. XRD shows that there is no new phase emerging after adding a small amount of nanomaterials. By FT-IR and SEM, it means that nanomaterials facilitate the reaction of geopolymer, making the modified geopolymer more compact. BET shows nano-SiO 2 especially modifies the pore distribution and pore structure of geopolymers. Additionally, nanomaterials have an improvement to the solidification/stabilization (S/S) of heavy metals.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
Journal of Coatings Technology and Research
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2022
·Vol. 19
·期 3
·947-957
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IF 2.339
Liu Xueting,Fan Ying,Li Yuan,Liu Wenkui,Wu Jingjing,Liu Changming,Yang Bin,Pang Zhicheng
This paper mainly studies an inorganic coating based on geopolymer technology. Metakaolin is used as raw material, and water glass solution is used as alkali activator to prepare geopolymer. The surface properties including crack resistance and scrub resistance of the obtained coating were improved by adding certain amount of resin and fillers such as silicone acrylic emulsion, mica powder, and MgO powder. The results show that when the contents of silicone acrylic emulsion, mica powder, and MgO powder are 19.00%, 3.20%, and 2.16–2.86%, respectively, the surface properties of the coating are optimal. Especially noteworthy is that adding MgO can enhance the surface properties of the prepared coating, the mechanism of which can be rationalized by the inhibited shrinkage of the coating via microcrack deformation, the enhanced compactness and the filled pores of the coating upon adding MgO. In addition, the flame retardancy of the samples was explored through thermal analysis and cone calorimeter.
研究领域:
材料科学
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化学工程
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涂料技术
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DOI
高影响因子
Materials Today Communications
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2025
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IF 4.5
Cheng Jianfeng,Zong Zihua,Dong Yanhui,Xie Jingli,Cao Shengfei,Zhang Qi,Peng Liyuan,Jiang Qiao
Geopolymers prepared from recycled fly ash have emerged as sustainable and effective solutions for the solidification of radioactive wastewater. In this study, fly ash-based geopolymers with varying 137 Cs concentrations are prepared, and their solidification effects as well as the compressive strength, porosity, microstructure, and leaching behavior after solidification are investigated. The results indicate the uniform incorporation of Cs into the prepared fly ash-based geopolymers. As the concentration of Cs in the geopolymers increases, the compressive strength decreases and porosity increases; however, the chemical structure remains almost unchanged. These observations are attributed to the electrostatic interaction between Cs + ions and the negatively charged [SiO 4 ] 4− and [AlO 4 ] 5− ions in the geopolymers. Moreover, the geopolymers exhibited lower leaching rates and cumulative leaching fractions in both deionized water and Beishan groundwater; the leaching rate and cumulative leaching fraction of 137 Cs in fly ash-based geopolymers were lower than the Chinese national standards. Further, the Cs solidification performances of the prepared geopolymers and traditional cement on real radioactive wastewater were compared. The fly ash-based geopolymers demonstrated a superior performance than traditional cement, making them a promising material for radioactive wastewater treatment. This study offers new insights into reducing radioactive waste and makes a substantial contribution to the knowledge of nuclear waste solidification processes employing fly ash-based geopolymers.
研究领域:
材料科学
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环境科学
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核废料管理
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产品关联
DOI
高影响因子
Journal of Building Engineering
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2025
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IF 7.4
Rongfeng Gao,Jiaxi Mao,Shengqian Ruan,Yilu Qiu,Shenhao Ye,Shikun Chen,Yi Liu,Dongming Yan
Eco-friendly geopolymers have demonstrated highly effective in immobilising organic liquid wastes, even outperforming Portland cement-based materials. To evaluate the feasibility of reusing liquid waste-containing geopolymers, this study systematically investigated the effects of immobilising three categories of organic liquids, i.e., vegetable oil, mineral oil, and organosilicon liquids, on the strength, wettability, water absorption, multi-scale pore structure, and chemical composition of metakaolin-based geopolymers (MKGs). Results indicate that mixing 18 % vegetable oil has minimal impact on the early-age (3 and 7 d) compressive strength but reduces long-term (28 d) strength by 29.2−34.9 %. Vegetable oil generally exists as small spherical droplets (10−50 μm) within the MKG matrix, acting as hydrophobic fillers that reduce the water absorption rate by 78.0−83.2 %. In contrast, mineral oil with low dosages of <4 % enhances the 28-d compressive strength by up to 20.4 %. Mineral oil tends to aggregate into larger droplets (20–100 μm) due to poor dispersion. Organosilicon liquids markedly improve hydrophobicity of MKG, with water transport inhibition varying based on the functional groups of organosilicons and the microstructure of MKG matrix. This work reveals the effects and underlying mechanisms of various organic liquids on the reaction and properties of MKG, providing guidance for assessing their engineering applicability, durability, and functionality, and promoting the full utilisation of available resources.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
Buildings
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2024
·Vol. 14
·期 12
·3918
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IF 3.1
Yanhui Dong,Mohamed R. El-Naggar,Runhui Gao,Yefan Li,Yixin Zhao
Microwave technology in geopolymer synthesis offers a transformative, sustainable alternative to traditional methods, enhancing material properties and production efficiency. However, the effects of microwave-induced changes on pore structure and their relationship with mechanical strength and environmental performance, such as heavy metal leachability, are not fully understood. This study investigates the impact of microwave pre-curing on geopolymers, focusing on how microwave power and duration influence their pore structure and environmental performance. A total of 48 mixtures were prepared using sodium silicate and sodium hydroxide as alkali activators, with metakaolin and fly ash as raw materials. The modulus was adjusted to 1.5, and the liquid-to-solid ratio was set at 1.6 for metakaolin and 0.7 for fly ash. Microwave irradiation power settings of 100 W, 300 W, 440 W, 600 W, and 800 W were tested. The heating times ranged from 30 s to 90 s at intervals of 15 s. Our findings reveal that optimal microwave settings (100 watts for 45 s) can significantly enhance mechanical properties, with compressive strengths reaching 15.9 MPa for fly ash-based and 9.094 MPa for metakaolin-based geopolymers. However, excessive microwave energy leads to increased porosity, with adverse effects on structural integrity. Moreover, microwave pre-curing effectively reduces heavy metal leachability. Chromium (III) was used in leaching tests and it was demonstrated that ion concentrations as low as 0.097 mg/L enhance environmental safety. Advanced techniques like Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray CT were applied for the analysis of the atomic bonding, phases and pore structure of the studied geopolymers along with their ability to withstand compression (MPa). Chromium (III) was encapsulated and its leached concentration was measured by ICP-MS to evaluate the performance of the synthesized geopolymers. These results underscore the need for precise control over microwave irradiation parameters to maximize the benefits while mitigating negative impacts. This study provides valuable insights into the controlled use of microwave technology for geopolymer synthesis, recommending optimal irradiation conditions for improved performance and sustainability and advancing sustainable construction materials. The developed geopolymers show promise for applications in construction, waste stabilization, and heavy metal immobilization, contributing to more sustainable and environmentally friendly materials in these industries.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2026
·
IF 8.9
Xiang Tian,Yan Zhan,Jie Wu,Shanchang Yi,Tianyong Jiang,Lei Wang
Silane coupling agents (SCAs) are widely recognized for improving the mechanical performance and crack resistance of geopolymers. However, previous studies have primarily focused on strength enhancement, while the influence of SCAs on crack mode evolution and micro-damage development remains poorly quantified. This study investigates the fracture regulation and damage evolution of methyltrimethoxysilane (MTMS)-modified metakaolin-based geopolymers through an integrated analysis of mechanical behavior, acoustic emission (AE), digital image correlation (DIC), and convolutional neural networks (CNNs). MTMS was incorporated at dosages ranging from 0 to 0.4 wt%, and CNN-based crack mode identification model was developed using a balanced AE dataset containing 1200 tensile and shear cracking signals. The results show that MTMS regulates both strength and fracture behavior in a dosage-dependent manner. The optimum strength enhancement was achieved at 0.2 wt% MTMS, increasing compressive and flexural strengths by 22.9% and 30.8%, respectively, while 0.3 wt% MTMS produced the highest peak displacement and longest time to peak load. AE analysis revealed a transition from instantaneous brittle damage to progressive energy-dissipating fracture with increasing MTMS dosage, whereas excessive MTMS induced defect-related brittleness recovery. The 2D-CNN achieved a validation accuracy of 96.67%, enabling reliable quantification of tensile and shear cracking evolution. CNN classification showed that 0.2 wt% MTMS promoted mixed-mode fracture by reducing tensile crack dominance and increasing shear-related damage activity. Combined DIC-AE analysis identified three fracture stages, including microcrack initiation, stable crack propagation, and unstable fracture. This study provides an intelligent framework for quantitatively linking SCA-induced fracture regulation with micro-damage evolution in geopolymers.
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产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2026
·
IF 8.9
Chao Kang,Yuqian Zhao,Yan Sun,Yanbiao Xu,Mengyao Sun,Shengchao Yang,Chenlong Duan,Li Wang,Tao Yang,Qiang Zhang,Jinpeng Qiao
FA and CCG synergistically enable high-performance one-part geopolymers. • CCG incorporation enhances strength while maintaining acceptable workability. • Moderate NaOH addition promotes geopolymerization and strength development. • The geopolymer with 40% CCG achieves 17.58 MPa at 28 d with balanced performance and sustainability. • Alkaline activator production dominates carbon emissions, embodied energy, and production cost. To promote the low-cost and large-scale utilization of coal-based solid wastes, this study aims to develop a one-part geopolymer using fly ash (FA) and calcined coal gangue (CCG) and to elucidate the effects of raw material proportions and auxiliary activators on its mechanical performance, fresh properties, and reaction behavior. The results indicate that with increasing CCG content, the compressive strength gradually increases, while the fluidity decreases. The incorporation of an appropriate amount of NaOH as an auxiliary activator significantly enhances early-age strength and promotes later strength development. Microstructural analyses indicate that CCG incorporation promotes geopolymerization, facilitating the formation of zeolite-like phases and contributing to strength development. Under the preferred conditions (40% CCG and NH/NS = 0.02), the geopolymer achieves compressive strengths of 5.17 MPa at 1 day and 17.58 MPa at 28 days, showing increases of 3.82 MPa and 10.23 MPa compared with the geopolymer without CCG at 1 and 28 days, respectively. Meanwhile, carbon emissions increase by 33.49% and the cost rises by only 6.39%. Further increasing the CCG content provides limited strength improvement while substantially reducing fluidity and increasing carbon emissions and cost. Overall, the results demonstrate the feasibility of producing low-cost one-part geopolymers through the synergistic utilization of FA and CCG. Download: Download high-res image (254KB) Download: Download full-size image
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DOI
高影响因子
危险品化学品经营许可证（带存储）