Effect of pH on the photocatalytic removal of silver ions by β-MnO2 particles
Sin-Ling Chiam , Anh Thi Le , Swee-Yong Pung , Fei-Yee Yeoh
International Journal of Minerals, Metallurgy, and Materials ›› 2021, Vol. 28 ›› Issue (2) : 325 -334.
Effect of pH on the photocatalytic removal of silver ions by β-MnO2 particles
The presence of silver ions (Ag(I)) in wastewater has a detrimental effect on living organisms. Removal of soluble silver, especially at low concentrations, is challenging. This paper presents the use of β-MnO2 particles as a photocatalyst to remove Ag(I) ions selectively from aqueous solution at various pH levels. Inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), field emission electron microscope (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron microscopy (XPS) were employed to determine the removal efficiency and to characterize the deposition of silver onto the surface of β-MnO2 particles. The optimum pH for the removal of Ag(I) ions was at pH 4 with 99% removal efficiency under 1 h of visible light irradiation. This phenomenon can be attributed to the electrostatic attraction between β-MnO2 particles and Ag(I) ions as well as the suppression of electron-hole recombination in the presence of H+ ions.
manganese oxide (MnO2) / silver / metal ion removal / photocatalyst
| [1] |
|
| [2] |
|
| [3] |
|
| [4] |
C.H. Chiang, L.H. Jiang, R.R. Fang, C.L. Chang, Y.P. Wang, and M.T. Hsieh, Copper-Silver Dual-component Metal Electroplating Solution and Electroplating Method for Semiconductor Wire, Google Patents, Appl. 15/801, 2019. |
| [5] |
|
| [6] |
|
| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
World Health Organization, Drinking Water, World Health Oraganization, 2019, [2019-11-15]. https://www.woo.int/newsroom/fact-sheets/detail/drinking-water |
| [14] |
|
| [15] |
|
| [16] |
|
| [17] |
|
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
|
| [22] |
|
| [23] |
|
| [24] |
|
| [25] |
|
| [26] |
|
| [27] |
|
| [28] |
|
| [29] |
|
| [30] |
|
| [31] |
|
| [32] |
|
| [33] |
|
| [34] |
|
| [35] |
|
| [36] |
|
| [37] |
|
| [38] |
|
| [39] |
|
| [40] |
|
| [41] |
|
| [42] |
|
| [43] |
|
/
| 〈 |
|
〉 |