The use of Silica Supported Nickel-Copper Oxide Catalyst for Photodegradation of Methylene Blue

Abstract

Photodegradation is a save and low cost methods to clean water bodies from some organic pollutants. The method has been developed in term of increasing the efficiency of the degradation capacity of photocatalyst. The photocatalyst working under visible light is the most desirable. The preparation of silica supported nickel-copper oxide [(Ni-Cu)Ox@SiO2] catalyst and the use of the catalyst in the photodegradation of methylene blue in the water are reported. The catalyst was prepared by impregnating the silica support into the mixture of nickel and copper salts, followed by calcination at 800○C for 4 hours. A series method of XRD, SEM-EDX, and UV-Vis Diffuse Reflectance has been used to characterize the catalyst. The catalyst adsorption test was undertaken in the dark, and the catalyst activity test for photodegradation of methylene blue was conducted under the sunlight. The XRD diffractogram of as prepared (Ni-Cu)Ox@SiO2 shows a weak-wide peak at 2θ = 21.8° indicating SiO2 tridymite, and has a crystallite size of 10.38 nm. The combination method of SEM and EDX confirms the formation of (Ni-Cu)Ox@SiO2. The (Ni-Cu)Ox@SiO2 catalyst has a relatively low bandgap energy and shows a good activity for photodegradation of blue methylene under sunlight. The adsorption of the methylene blue on the (Ni-Cu)Ox@SiO2 follows the Langmuir isotherm pattern.

Green synthesis of doped Co3O4 nanocatalysts using organic template for fast azo dye degradation from aqueous environment

“…1. It is reported that O‐ and OH‐containing compounds reduce the azo group of MO leading to the color discharging of the dye 11,53,54 . In the present study, the catalytic efficiency of Co 3 O 4 was markedly increased after addition of NiO or PdO/Pd indicating the catalytic wet oxidation (CWO) process, which depends on oxygen vacancies to degrade organic pollutants.…”

“…Therefore, incorporated carbonaceous phytochemicals, revealed by GC–MS in Figs 2(d)–(f), facilitated the flow of photogenerated charge carriers (electrons and holes in opposite directions) to prolong electron lifetime, which then utilized light with superior efficiency. Consequently, on the bases of the holes and electrons of mixed oxides as well as the incorporated carbonaceous material, the mechanism of degradation of MO can be explained as follows: 11,40,53–56 …”

“…40 Therefore, incorporated carbonaceous phytochemicals, revealed by GC-MS in Figs 2(d)-(f), facilitated the flow of photogenerated charge carriers (electrons and holes in opposite directions) to prolong electron lifetime, which then utilized light with superior efficiency. Consequently, on the bases of the holes and electrons of mixed oxides as well as the incorporated carbonaceous material, the mechanism of degradation of MO can be explained as follows: 11,40,[53][54][55][56] Firstly, electrons are produced by sunlight in the case of photocatalysis and by CWO in the case of dark conditions, then these electrons produce • OH radicals by reacting with atmospheric and dissolved O 2 and H + in water giving hydroxyl radicals. The holes of valence band react with these hydroxyl groups at the surface of catalysts to give • OH radicals which then finally react with the dye molecules to degrade them.…”

Optimasi Waktu dan Suhu Hidrotermal pada Sintesis Nanotabung TiO2 Terdoping Nitrogen untuk Aplikasi Fotokatalis

“…Nanotabung N-TiO2 hasil sintesis dikarakterisasi menggunakan alat XRD dengan sumber radiasi Cu Kα Gambar 1 menunjukkan bahwa material hasil sintesis N-TiO2 pada variasi suhu hidrotermal diasumsikan memiliki struktur nanotabung dengan ditandai munculnya puncak dibawah 20º sekitar pada 2 = 11º namun kemungkinan mengalami ketidakstabilan yang berakibat puncak bergeser dikarenakan puncak belum terlalu jelas terlihat [6,9,12]. Perubahan intensitas pada puncak difraktogram hasil sintesis variasi suhu hidrotemal mempengaruhi struktur kristalografi dan morfologi serta sifat fisika-kimia [6,8]. Berdasarkan data yang diperoleh, ukuran kristal setiap fase dihitung berdasarkan nilai FWHM dengan menggunakan persamaan Debrye-Scherrer.…”