| 462 | 0 | 103 |
| 下载次数 | 被引频次 | 阅读次数 |
煤系固废的高值化利用在推动绿色低碳发展和实现“双碳”目标中扮演着至关重要的角色。基于煤系固废资源粉煤灰和煤气化渣的富硅特性，分别以粉煤灰和煤气化渣为前驱体，通过熔盐辅助镁热还原工艺结合碳包覆策略和一步镁热还原工艺制备出具有“核壳结构”的粉煤灰基硅碳复合材料和具有“镶嵌结构”的煤气化渣基硅碳连生体复合材料。2种复合材料均具有较高的比表面积(215.7 m2·g–1和274.8 m2·g–1)和丰富的层次孔结构(微孔和介孔协同分布)；粉煤灰基硅碳复合材料中碳组分占比28.1%(质量分数)，其丰富的sp3结构缺陷和边缘缺陷能够增加锂离子的吸附活性位点；煤气化渣基硅碳连生体复合材料中碳组分占比36.9%，其较高含量的sp2碳能够增强复合材料的结构稳定性且丰富的堆叠缺陷能够为锂离子提供传输路径。两种复合材料用作锂离子电池负极时在50 mA·g–1电流密度下可逆容量分别为800 mA·h·g–1和420 mA·h·g–1，且在500 mA·g–1电流密度下经300次循环后可逆容量仍可达348 mA·h·g–1和334 mA·h·g–1，展现出良好的倍率性能及循环稳定性，为煤系固废的高值化利用提供了新路径，有利于推动低成本、高性能储能材料的开发和应用。
Abstract：Introduction The large-scale mining and processing of coal resources inevitably result in the continuous generation and accumulation of solid wastes such as fly ash and coal gasification slag. However, their utilization rate remains low, with primary dependence on open-air stockpiling, leading to substantial resource depletion and ecological hazards. The existing resource utilization of fly ash and coal gasification slag is still confined to low-value-added fields like construction materials and agriculture. It is critically necessary to explore their inherent resource properties and develop high-value utilization pathways, thereby addressing environmental challenges, while enhancing economic benefits. Some researches reveal that fly ash and coal gasification slag both contain abundant silicon components in their phase compositions. This characteristic endows them with significant potential as precursors for synthesizing silicon anode materials. This study was to fabricate silicon/carbon composites with fly ash and coal gasification slag as precursors, provide novel insights into the high-value application of coal-based solid waste resources and expand the methodology for low-cost preparation of silicon-based materials for lithium-ion batteries. Methods In the fabrication of distinct silicon-carbon composites, a fly ash-derived silicon material was prepared via uniformly grinding a mixture with 1 g of fly ash, 1 g of magnesium powder and 2 g of sodium chloride. Afterwards, the ground mixture was heated in argon atmosphere by magnesiothermic reduction at 750 ℃ for 8 h. A purified silicon material was obtained after sequential washing with hydrochloric acid and hydrofluoric acid. For the fly ash-derived silicon-carbon composite, this silicon material was dispersed with phenolic resin at an equal mass ratio, modified via cetyltrimethylammonium bromide assistance, and carbonized at 800 ℃ for 2 h to form a carbon-coated structure. In contrast, the coal gasification slag-derived composite was synthesized in a single step via subjecting 1 g of coal gasification slag, 0.6 g of magnesium powder, and 2 g of sodium chloride to identical magnesiothermic reduction conditions, thereby retaining inherent carbon to generate an interconnected silicon-carbon architecture. The morphologies and microcrystalline structures of all the obtained samples were analyzed by X-ray diffraction, Raman spectroscopy, X-ray energy dispersive spectroscopy, scanning electron microscopy, and transmission electron microscopy. The thermal behavior was evaluated by thermogravimetric analysis, and the microstructures were characterized via BET specific surface area and pore size distribution measurements. The two composite materials were assembled into lithium-ion half-cells for charge–discharge cycling, cyclic voltammetry, and impedance testing to evaluate their lithium storage performance. Results and discussion Silicon materials obtained via the magnesiothermic reduction process with fly ash as a precursor exhibit a high crystallinity, primarily composed of densely packed crystalline particles. The corresponding fly ash-based silicon-carbon composite fabricated via a carbon-coating strategy exhibits a “core-shell structure” with a carbon content of 28.1%. This carbon layer predominantly consists of amorphous carbon enriched with abundant sp3-hybridized structural defects and edge disorders, significantly affecting the interfacial charge transfer dynamics. In contrast, the coal gasification slag-derived composite synthesized via one-step magnesiothermic reduction demonstrates a distinctive mosaic architecture incorporating 36.9% carbon with substantially enhanced sp2-hybridized carbon domains, thus facilitating a superior electrical conductivity. Fly ash-based silicon-carbon composite and coal gasification slag-derived composite both have high specific surface areas(i.e., 215.7 and 274.8 m2·g-1) and rich hierarchical pore structures(i.e., synergistic distribution of microporous and mesoporous pores). As lithium-ion battery anodes, fly ash-derived silicon-carbon composite and coal gasification slag-derived silicon-carbon composite exhibit reversible capacities of 800 and 420 mA·h·g-1 at 50 mA·g-1, respectively. These composites maintain reversible capacities of 348 and 334 mA·h·g-1 after 300 cycles at 500 mA·g-1, respectively, showing superior rate capability and cycling stability. This study demonstrates that silicon-carbon composites with high-performance lithium storage characteristics can be prepared by using low-cost coal-based solid waste–fly ash and coal gasification slag as precursors, which is helpful for promoting the development and application of low-cost, high-performance energy storage materials. Conclusions A silicon-carbon composite with a “core–shell structure” was synthesized by using fly ash as a precursor through a magnesia-based reduction process combined with a carbon coating strategy. Also, a silicon-carbon intergrown composite exhibiting an “mosaic architecture” was prepared by using coal gasification slag as a precursor by a one-step magnesia-based reduction process. The abundant sp3 structural defects and edge defects in fly ash-based silicon-carbon composite could enhance its lithium storage capacity, while the significant sp2 carbon in the coal gasification slag-based composite could improve its structural stability. Consequently, the composites both exhibited excellent rate performance and cycling stability when used as anodes in lithium-ion batteries. This study could provide some insights for the high-value utilization of coal-based solid waste resources and expand avenues for low-cost preparation of silicon-based materials for lithium-ion batteries.
[1]杨科,何淑欣,何祥,等.煤电化基地大宗固废“三化”协同利用基础与技术[J].煤炭科学技术, 2024, 52(4):69–82.YANG Ke, HE Shuxin, HE Xiang, et al. Coal Sci Technol, 2024, 52(4):69–82.
[2]张国卿,宋舒波,王兴瑞,等.煤固废基分子筛的制备及其应用进展[J].化工进展, 2024, 43(5):2311–2323.ZHANG Guoqing, SONG Shubo, WANG Xingrui, et al. Chem Ind Eng Prog, 2024, 43(5):2311–2323.
[3]韩崇刚.“双碳”目标下煤基固废高值化处理与综合利用研究[J].煤炭经济研究, 2023, 43(12):30–35.HAN Chonggang. Coal Econ Res, 2023, 43(12):30–35.
[4]常瑞祺,张建波,李会泉,等.煤基固废制备胶凝材料研究进展及应用[J].洁净煤技术, 2024, 30(2):316–330.CHANG Ruiqi, ZHANG Jianbo, LI Huiquan, et al. Clean Coal Technol, 2024, 30(2):316–330.
[5] YANG L, LI D L, ZHU Z N, et al. Effect of the intensification of preconditioning on the separation of unburned carbon from coal fly ash[J]. Fuel, 2019, 242:174–183.
[6]刘仓,金亮,陈航超,等.粉煤灰资源化提取研究进展[J].煤炭工程, 2021, 53(增刊1):127–133.LIU Cang, JIN Liang, CHEN Hangchao, et al. Coal Eng, 2021,53(Suppl 1):127–133.
[7]曲江山,张建波,孙志刚,等.煤气化渣综合利用研究进展[J].洁净煤技术, 2020, 26(1):184–193.QU Jiangshan, ZHANG Jianbo, SUN Zhigang, et al. Clean Coal Technol, 2020, 26(1):184–193.
[8]艾伟东,田一茹,李航,等.煤气化渣基介孔二氧化硅在聚丙烯中除味性能[J].应用化工, 2025, 54(7):1758–1763.AI Weidong, TIAN Yiru, LI Hang, et al. Appl Chem Ind, 2025, 54(7):1758–1763.
[9] GUO X Y, ZHAO Z L, GAO X L, et al. Study on the adsorption performance of modified high silica fly ash for methylene blue[J]. RSC Adv, 2024, 14(30):21342–21354.
[10]徐啟斌,牛香力,陈婷婷,等.煤气化渣合成4A分子筛及其吸附性能研究[J].硅酸盐通报. 2023, 42(6):2251–2261.XU Qibin, NIU Xiangli, CHEN Tingting, et al. B Chin Ceram Soc,2023, 42(6):2251–2261.
[11] MURAKAMI T, OTSUKA K, FUKASAWA T, et al. Hierarchical porous zeolite synthesis from coal fly ash via microwave heating[J].Colloids Surf A Physicochem Eng Aspects, 2023, 661:130941.
[12] KARRI D S N, EGA S P, PERUPOGU V, et al. Enhancing the electrochemical performance of polyaniline using fly ash of coal waste for supercapacitor application[J]. ChemistrySelect, 2021, 6(10):2576–2589.
[13] WANG M, WANG H, WANG N, et al. The introduction of oxygen vacancy defects in Al-doped transition metal silicates derived from fly ash for high-performance aqueous potassium ion capacitor[J].Electrochim Acta, 2022, 434:141310.
[14] WANG B, GUO Y H, DU J J, et al. Green utilization of silicon slime:Recovery of Si and synergetic preparation of porous silicon as lithium-ion battery anode materials[J]. Ionics, 2023, 29(12):5099–5110.
[15] BAO Z H, WEATHERSPOON M R, SHIAN S, et al. Chemical reduction of three-dimensional silica micro-assemblies into microporous silicon replicas[J]. Nature, 2007, 446(7132):172–175.
[16] MA X W, FEI W D, LIU J M, et al. Energetic characteristics of highly reactive Si nanoparticles prepared by magnesiothermic reduction of mesoporous SiO2[J]. Chem Eng J, 2024, 481:148542.
[17] WAN N, WANG L, LI S Y, et al. Engineering high-rate anode materials via montmorillonite-derived silicon nanosheets[J]. Small,2025:e2412705.
[18] RASOULI A, TSOUTSOUVA M, SAFARIAN J, et al. Kinetics of magnesiothermic reduction of natural quartz[J]. Materials, 2022,15(19):6535.
[19] DU J J, GUO Y H, ZHANG J G, et al. Green transformation of photovoltaic silicon mud to a high-performance P-Si@RGO anode material by magnesium thermal reduction via electrostatic assembly technology[J]. Diam Relat Mater, 2025, 152:111947.
[20] JIANG Y, ZHANG Y, YAN X M, et al. A sustainable route from fly ash to silicon nanorods for high performance lithium ion batteries[J].Chem Eng J, 2017, 330:1052–1059.
[21]张建波,李占兵,杨晨年,等.粉煤灰中非晶态硅赋存形态及定量分析方法研究[J].洁净煤技术, 2019, 25(3):116–121.ZHANG Jianbo, LI Zhanbing, YANG Chennian, et al. Clean Coal Technol, 2019, 25(3):116–121.
[22]乔会,左岳,屈洁,等.煤气化渣残碳的分离及应用研究进展[J].洁净煤技术, 2024, 30(增刊2):103–111.QIAO Hui, ZUO Yue, QU Jie, et al. Clean Coal Technol, 2024,30(Suppl 2):103–111.
[23] TANG K, RASOULI A, SAFARIAN J, et al. Magnesiothermic reduction of silica:A machine learning study[J]. Materials, 2023,16(11):4098.
[24] MA X W, FEI W D, ZHANG X D, et al. Preparation of mesoporous Si nanoparticles by magnesiothermic reduction for the enhanced reactivity[J]. Molecules, 2023, 28(7):3274.
[25] HONG F, ZHOU R X, GAO C Y, et al. Fabrication of porous SiOx/nanoSi@C composites with homogeneous silicon distribution for high-performance Li-ion battery anodes[J]. J Alloys Compd, 2023, 947:169511.
[26] XIA H T, MU X J, ZHOU J H, et al. Realization of high-capacity coulombic efficiency in sodium alginate/carbon nanotube double network coated Si-anode for lithium-ion batteries[J]. Sustain Mater Technol, 2024, 40:e00940.
[27] SHI J W, ZU L H, GAO H Y, et al. Silicon-based self-assemblies for high volumetric capacity Li-ion batteries via effective stress management[J]. Adv Funct Mater, 2020, 30(35):2002980.
[28] ZHANG Y, TANG W, GAO H P, et al. Monolithic layered silicon composed of a crystalline-amorphous network for sustainable lithium-ion battery anodes[J]. ACS Nano, 2024, 18(24):15671–15680.
[29]马耀东.硅基复合材料负极的制备及其在锂离子电池中的应用研究[D].兰州:兰州大学, 2023.MA Yaodong. Preparation of silicon-based composite negative electrode and its application in lithium ion battery[D]. Lanzhou:Lanzhou University, 2023.
[30] WANG D, KONG L Y, ZHANG F, et al. Porous carbon-coated silicon composites for high performance lithium-ion batterie anode[J]. Appl Surf Sci, 2024, 661:160076.
[31] WANG X, ZENG H H, XING B L, et al. Porous carbon nanoflakes constructed from anthracite-derived aromatic fragments as efficient anode for lithium-ion storage[J]. J Energy Storage, 2025, 118:116268.
[32]邢宝林,徐巧妙,曾会会,等.褐煤基硬炭微观结构调控及其储钠特性[J].煤炭学报, 2024, 49(4):2086–2098.XING Baolin, XU Qiaomiao, ZENG Huihui, et al. J China Coal Soc,2024, 49(4):2086–2098.
[33] ZENG H T, KANG W W, XING B L, et al. Microstructure modulation of hard carbon derived from long-flame coal to improve electrochemical sodium storage performances[J]. Fuel Process Technol,2025, 267:108159.
[34] ZHAO F F, ZHAO M, DONG Y R, et al. Facile preparation of micron-sized silicon-graphite-carbon composite as anode material for high-performance lithium-ion batteries[J]. Powder Technol, 2022, 404:117455.
[35] CHANG X H, SUN B X, XIE Z W, et al. Structure robustness and Li+diffusion kinetics in amorphous and graphitized carbon based Sn/C composites for lithium-ion batteries[J]. J Electroanal Chem, 2019, 854:113529.
[36] XING B L, SHI F, JIN Z Z, et al. A facile ice-templating-induced puzzle coupled with carbonization strategy for kilogram-level production of porous carbon nanosheets as high-capacity anode for lithium-ion batteries[J]. Carbon Energy, 2024, 6(12):e633.
[37] GUO H, ZHAO S D, XING B L, et al. A space-confined carbonization strategy to prepare P-doped carbon nanosheets using expanded vermiculite as a template for high-performance lithium-ion battery anode[J]. J Energy Storage, 2024, 84:111005.
[38] HOU L, XING B L, KANG W W, et al. Aluminothermic reduction synthesis of porous silicon nanosheets from vermiculite as high-performance anode materials for lithium-ion batteries[J]. Appl Clay Sci, 2022, 218:106418.
[39] LIU Q, JI Y X, YIN X M, et al. Magnesiothermic reduction improved route to high-yield synthesis of interconnected porous Si@C networks anode of lithium ions batteries[J]. Energy Storage Mater, 2022, 46:384–393.
[40] WEI S S, CHEN Q Z, ZHU R L, et al. One-pot synthesis of interconnected carbon-coated silicon nanosheets from clay minerals for high-performance lithium-ion battery anodes[J]. Appl Clay Sci, 2024,254:107388.
[41] LI X, CHEN Z Y, LIU X W, et al. Efficient lithium transport and reversible lithium plating in silicon anodes:Synergistic design of porous structure and LiF-rich SEI for fast charging[J]. Adv Funct Mater, 2024, 34(33):2401686.
[42] WANG Y, XU C, FU J J, et al. Preparation of high-performance SiOx anode materials via dual interfacial reinforcement strategy[J]. Chem Eng J, 2025, 510:161895.
[43] LIN Y J, JIA J B, WANG J, et al. A simple and effective low-temperature pyrolysis control strategy to enhance the sodium storage performance of lignite-based carbon materials[J]. Chem Eng J,2025, 504:158858.
[44]赵明远,杨绍斌,董伟,等.基于埃洛石的硅纳米管制备及储锂性能[J].硅酸盐学报, 2021, 49(7):1457–1465.ZHAO Mingyuan, YANG Shaobin, DONG Wei, et al. J Chin Ceram Soc, 2021, 49(7):1457–1465.
[45] KANG M S, KIM S, HEO I, et al. Revealing partial graphitization of amorphous carbon in SiO2@C during magnesiothermic reduction[J].ACS Appl Energy Mater, 2024, 7(15):6419–6428.
[46] YANG L L, SONG R F, WAN D Y, et al. Magnesiothermic reduction SiO coated with vertical carbon layer as high-performance anode for lithium-ion batteries[J]. J Energy Storage, 2024, 99:113440.
[47] ZHANG C L, LI J J, FENG Y Y, et al. Recycling silicon cutting waste from photovoltaic industry into high-performance anodes for lithium-ion batteries[J]. ACS Sustainable Chem Eng, 2024, 12(37):14099–14108.
[48] BISHOYI S S, BEHERA S K. Fabrication and electrochemical performance of Si-C composite nanostructures with SiO2 sacrificial agent for LIB anode[J]. J Alloys Compd, 2024, 982:173766.
[49] TAO J M, YAN Z R, YANG J S, et al. Boosting the cell performance of the SiOx@C anode material via rational design of a Si-valence gradient[J]. Carbon Energy, 2022, 4(2):129–141.
[50] OU S Q, LIU C, YANG R G, et al. Supramolecular-driven construction of multilayered structure by modified hummers method for robust silicon anode[J]. Energy Storage Mater, 2024, 73:103814.
[51] SHI F, XING B L, ZENG H H, et al. Facile synthesis of ultrathin carbon nanosheets through Na Cl–KCl templates coupled with ice-induced assembly strategy from carbon quantum dots as lithium-ion batteries anodes[J]. J Alloys Compd, 2024, 976:173325.
[52] XING B L, MENG W B, LIANG H, et al. Flexible coal-derived carbon fibers via electrospinning for self-standing lithium-ion battery anodes[J]. Int J Min Sci Technol, 2024, 34(12):1753–1763.
基本信息:
DOI：10.14062/j.issn.0454-5648.20250449
中图分类号:TM912;TB332;O646
引用信息:
[1]赵赛丹,邢宝林,张亚超,等.煤系固废基硅/碳复合材料的结构设计与电化学储能[J].硅酸盐学报,2025,53(12):3585-3599.DOI:10.14062/j.issn.0454-5648.20250449.
基金信息:
国家自然科学基金（52274261,52304284,52474290）; 河南省重点科技项目（252102231063）