Niu Yanhui, Yu Wenbin, Yang Shuguang, Wan Quan
School of Chemistry and Materials Science, Guizhou Education University, Guiyang, 550018, China.
State Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of Sciences, Institute of Geochemistry, Guiyang, 550081, China.
Sci Rep. 2024 Jun 12;14(1):13521. doi: 10.1038/s41598-024-64337-5.
This research delved into the influence of mesoporous silica's surface charge density on the adsorption of Cu. The synthesis of mesoporous silica employed the hydrothermal method, with pore size controlled by varying the length of trimethylammonium bromide (CTAB, n = 12, 14, 16) chains. Gas adsorption techniques and transmission electron microscopy characterized the mesoporous silica structure. Surface charge densities of the mesoporous silica were determined through potentiometric titration, while surface hydroxyl densities were assessed using the thermogravimetric method. Subsequently, batch adsorption experiments were conducted to study the adsorption of Cu in mesoporous silica, and the process was comprehensively analyzed using Atomic absorption spectrometry (AAS), Fourier transform infrared (FTIR), and L3 edge X-ray absorption near edge structure (XANES). The research findings suggest a positive correlation between the pore size of mesoporous silica, its surface charge density, and the adsorption capacity for Cu. More specifically, as the pore size increases within the 3-4.1 nm range, the surface charge density and the adsorption capacity for Cu also increase. Our findings provide valuable insights into the relationship between the physicochemical properties of mesoporous silica and the adsorption behavior of Cu, offering potential applications in areas such as environmental remediation and catalysis.
本研究深入探讨了介孔二氧化硅的表面电荷密度对铜吸附的影响。介孔二氧化硅的合成采用水热法，通过改变溴化三甲基铵（CTAB，n = 12、14、16）链的长度来控制孔径。采用气体吸附技术和透射电子显微镜对介孔二氧化硅结构进行表征。通过电位滴定法测定介孔二氧化硅的表面电荷密度，同时采用热重法评估表面羟基密度。随后，进行批量吸附实验以研究介孔二氧化硅对铜的吸附，并使用原子吸收光谱法（AAS）、傅里叶变换红外光谱法（FTIR）和L3边X射线吸收近边结构（XANES）对该过程进行全面分析。研究结果表明，介孔二氧化硅的孔径、表面电荷密度与对铜的吸附容量之间存在正相关关系。更具体地说，当孔径在3 - 4.1纳米范围内增加时，表面电荷密度和对铜的吸附容量也会增加。我们的研究结果为介孔二氧化硅的物理化学性质与铜的吸附行为之间的关系提供了有价值的见解，在环境修复和催化等领域具有潜在应用。
