Abstract

In this work, mesoporous CdS (130.7 m²/g) was prepared; then, ZnS was deposited by chemical bath deposition (CBD) and successive ionic layer adsorption and reaction (SILAR) method, to get CdS–ZnS(C) and CdS–ZnS(S), respectively. Subsequently, the highest efficient binary hybrid was sensitized with polyaniline to produce CdS–ZnS–PANI for the first time. XRD and EDX analyses confirmed the coating of CdS with ZnS using CBD and SILAR method. The careful examination for the surface morphology of the binary hybrids illustrated that CdS–ZnS(S) has uniform morphology and the CdS nanoparticles are homogeneously overcoated with ZnS. In contrast, CdS–ZnS(C) exhibits inhomogeneous surface, where there are ZnS particles that aggregate together and there is another region which contains ZnS deposited onto CdS. The estimated band gap of CdS, CdS–ZnS(S), and CdS–ZnS–PANI was 2.36 eV, 2.44 eV, and 1.9 eV, respectively. The removal efficiency for cationic and anionic dyes single and/or in combination using CdS, ZnS, CdS–ZnS(C), CdS–ZnS(S), PANI, and CdS–ZnS–PANI was studied. The effect of the amount of ZnS loaded by SILAR process on the activity of the CdS–ZnS(S) was presented. The results proposed that CdS–ZnS(S) exhibits selective adsorption and high removal efficiency for cationic dye compared to CdS–ZnS(C) due to higher negative zeta potential and large surface area. The CdS–ZnS–PANI ternary nanocomposite showed uptake efficiency of 96.7% for cationic dye (MB) and 94.3% for anionic dye (MO) in a mixed dye solution after 10 min. Finally, the possible adsorption mechanism was proposed.

Graphic abstract

摘要

在这项工作中，中孔CdS（130.7 m ²/ g）已准备好；然后，通过化学浴沉积（CBD）和连续离子层吸附和反应（SILAR）方法沉积ZnS，分别得到CdS–ZnS（C）和CdS–ZnS（S）。随后，最高效的二元杂种首先用聚苯胺敏化，以生产CdS–ZnS–PANI。XRD和EDX分析证实了使用CBD和SILAR方法用ZnS涂覆CdS。对二元杂化体的表面形态进行仔细检查后发现，CdS–ZnS（S）具有均匀的形态，并且CdS纳米粒子均匀地覆盖有ZnS。相反，CdS–ZnS（C）表现出不均匀的表面，其中有ZnS颗粒聚集在一起，而另一个区域包含沉积在CdS上的ZnS。CdS，CdS–ZnS（S）和CdS–ZnS–PANI的估计带隙为2.36 eV，2.44 eV和1。分别为9 eV。研究了使用CdS，ZnS，CdS–ZnS（C），CdS–ZnS（S），PANI和CdS–ZnS–PANI对单一和/或组合的阳离子和阴离子染料的去除效率。提出了通过SILAR工艺加载的ZnS量对CdS–ZnS（S）活性的影响。结果表明，与CdS–ZnS（C）相比，CdS–ZnS（S）对阳离子染料表现出选择性吸附和高去除效率，这归因于其较高的负ζ电势和较大的表面积。在混合染料溶液中10分钟后，CdS–ZnS–PANI三元纳米复合材料对阳离子染料（MB）的吸收效率为96.7％，对阴离子染料（MO）的吸收效率为94.3％。最后，提出了可能的吸附机理。研究了CdS–ZnS–PANI。提出了通过SILAR工艺加载的ZnS量对CdS–ZnS（S）活性的影响。结果表明，与CdS–ZnS（C）相比，CdS–ZnS（S）对阳离子染料表现出选择性吸附和高去除效率，这归因于其较高的负ζ电势和较大的表面积。在混合染料溶液中10分钟后，CdS–ZnS–PANI三元纳米复合材料对阳离子染料（MB）的吸收效率为96.7％，对阴离子染料（MO）的吸收效率为94.3％。最后，提出了可能的吸附机理。研究了CdS–ZnS–PANI。提出了通过SILAR工艺加载的ZnS量对CdS–ZnS（S）活性的影响。结果表明，与CdS–ZnS（C）相比，CdS–ZnS（S）对阳离子染料表现出选择性吸附和高去除效率，这归因于其较高的负ζ电势和较大的表面积。在混合染料溶液中10分钟后，CdS–ZnS–PANI三元纳米复合材料对阳离子染料（MB）的吸收效率为96.7％，对阴离子染料（MO）的吸收效率为94.3％。最后，提出了可能的吸附机理。结果表明，与CdS–ZnS（C）相比，CdS–ZnS（S）对阳离子染料表现出选择性吸附和高去除效率，这归因于其更高的负ζ电势和较大的表面积。在混合染料溶液中10分钟后，CdS–ZnS–PANI三元纳米复合材料对阳离子染料（MB）的吸收效率为96.7％，对阴离子染料（MO）的吸收效率为94.3％。最后，提出了可能的吸附机理。结果表明，与CdS–ZnS（C）相比，CdS–ZnS（S）对阳离子染料表现出选择性吸附和高去除效率，这归因于其较高的负ζ电势和较大的表面积。在混合染料溶液中10分钟后，CdS–ZnS–PANI三元纳米复合材料对阳离子染料（MB）的吸收效率为96.7％，对阴离子染料（MO）的吸收效率为94.3％。最后，提出了可能的吸附机理。

图形摘要