Synthetic incorporation of palladium-nickel bimetallic nanoparticles within mesoporous silica/silica nanoparticles as efficient and cheaper catalyst for both cationic and anionic dyes degradation

Abstract

Nickel-palladium bimetallic nanocrystallite supported mesoporous silica/silica nanoparticles (MSPs/MSNPs) made at a controlled ratio of Pd/Ni via organotrialkoxysilane mediated reduction of palladium cations are reported. The organotrialkoxysilane serve as a template for the stabilization and formation of bimetallic Pd-Ni nanocrystallite within MSPs/MSNPs that are characterized by TEM, EDX, HR-SEM, HR-MS, XRD, BET and Elemental mapping analysis, kinetic analysis for degradation of both cationic and anionic dyes, i.e., rhodamine B and congo red, respectively. The nanocrystallite inserted MSNPs of particle diameter 200 nm justify faster degradation with rate constant to the order of 6.9 x10⁻²s⁻¹ as compared to that for MSPs of 50 µm to the order of 3.2 x10⁻² s⁻¹ for 15 ppm Rh B within 50 s as compared to that for mesoporous silica of 50 µm within 110 s under similar conditions with analogous observation for the degradation of congo red. Heterogeneous support is fully recyclable and shows 100% catalytic activity even after five subsequent applications. The degradation dynamics have further been evaluated based on fluorescent spectra and HR-MS analysis.

Keywords:

• Bimetallic nanocrystallite inserted mesoporous silica nanoparticles
• Congo red
• Rhodamine B
• fluorescence imaging of toxic dye
• BET analysis
• TEM analysis
• EDX analysis
• mapping and HR-MS

Additional information

Funding

This work was supported by Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organisation (LSRB-316).