Mechanochemical Synthesis of Tungstophosphoric Acid Based High Efficiency Photocatalysts

Syed Waqar Hussain Shah; Omama Zafar; Irum Bibi; Saifullah Zafar Khan; Sadaf Bibi; Kashif  Ali

doi:10.17721/fujcV14I1P83-93

Authors

Syed Waqar Hussain Shah Department of Chemistry, Hazara University, Mansehra
Omama Zafar Hazara University Mansehra
Irum Bibi Hazara University Mansehra
Saifullah Zafar Khan Abbottabad University of Science and Technology Havelian
Sadaf Bibi Beijing Institute of Technology
Kashif Ali Hubei University Wuhan

DOI:

https://doi.org/10.17721/fujcV14I1P83-93

Keywords:

tungstophosphoric acid, photocatalysis, dye degradation, mechanochemical, proton-transfer

Abstract

Organic-inorganic hybrids (WT) based on tungstophosphoric acid (TPA) and tris(hydroxymethyl)aminomethane (TRIS) were synthesized by a sustainable, solventless, mechanochemical route. SEM and Powder X-ray diffraction (PXRD) showed a shift from bulk crystallinity in TPA to nanocrystalline domains in WT. Rietveld refinement revealed an expansion of Keggin unit upon hybrid formation. Proton transfer and alteration in H-bonding interactions were established through ATR-IR spectroscopy. WT had higher thermal stability compared to TPA. Under solar irradiation, a superior malachite green (MG) removal ranging from 92.5 – 98.5% was achieved with 1.2 g of WT. This work discusses the modification of polyoxometalates for high-performance light-aided catalysis.

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