ABSTRACT

Hydrogel material is considered to be one of the effective adsorbents widely used to remove organic pollutants. However, the poor mechanical properties of some hydrogels limit their applications. Herein, we prepared composite hydrogels, for which acrylic acid (AA) and acrylamide (AM) were cross-linked and polymerised as the main substrate with adsorption function, while CdS nanoparticles were mainly used as reinforced material. Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FTIR), two-dimensional infrared vibrational echo spectroscopy (2D-IR), and thermal gravimetric analyzer (TGA) were used to determine the physical and chemical structures of the hydrogels. The effects of the composition of AA, AM, and CdS on the mechanical properties and adsorption behaviours of the hydrogels were investigated. Besides, based on the great potential photocatalytic application value for wastewater remediation under the sunlight of CdS, the influence of the CdS doping amount on the photocatalytic property was also studied. As a result, when the mass ratio of AA to AM was 5:5, the hydrogel showed the best mechanical properties, and along with increasing the amount of CdS, the mechanical strength of the hydrogel was significantly enhanced from 0.445 MPa to 1.014 MPa. Besides, the composite hydrogels showed high adsorption and photocatalytic degradation synergistic clearance effect on methylene blue. Thus, the introduction of CdS photocatalytic nanoparticles may be an efficient and economical approach towards bifunctional hydrogel materials with enhanced mechanical property and photocatalytic degradation for wastewater remediation.

摘要

水凝胶材料被认为是广泛用于去除有机污染物的有效吸附剂之一。然而，一些水凝胶较差的机械性能限制了它们的应用。在此，我们制备了复合水凝胶，其中丙烯酸（AA）和丙烯酰胺（AM）作为具有吸附功能的主要基材进行交联和聚合，而CdS纳米颗粒主要用作增强材料。使用扫描电子显微镜（SEM）、傅里叶变换红外光谱仪（FTIR）、二维红外振动回波光谱仪（2D-IR）和热重分析仪（TGA）来确定水凝胶的物理和化学结构。研究了AA、AM和CdS的组成对水凝胶力学性能和吸附行为的影响。除了，基于CdS在阳光下光催化废水修复的巨大潜在应用价值，还研究了CdS掺杂量对光催化性能的影响。结果，当AA与AM的质量比为5:5时，水凝胶表现出最佳的力学性能，随着CdS用量的增加，水凝胶的机械强度从0.445 MPa显着提高到1.014 MPa。此外，复合水凝胶对亚甲基蓝表现出高吸附和光催化降解协同清除作用。因此，引入 CdS 光催化纳米粒子可能是一种有效且经济的双功能水凝胶材料，具有增强的机械性能和用于废水修复的光催化降解。