Sm-Doped (1 – x)Pb(Mg_1/3Nb_2/3)O₃-xPbTiO₃ Nanostructures for Piezocatalytic Dye Degradation

Abstract

Mechanical energy can be directly transformed into chemical energy by piezoelectric materials, namely, piezocatalysis, which is a potential tactic for renewable clean energy collection and environmental purification. The piezocatalytic efficiency strongly relies on the piezoelectric property and free charge concentration of piezocatalysts. Here, four samarium-doped (1 – x)­Pb­(Mg1/3Nb2/3)­O3-xPbTiO3 nanostructures were designed to investigate the correlation between the piezoelectric property and piezocatalytic performance. The diverse dye degradation efficiencies confirmed the high piezoelectric coefficient toward high catalytic activity. The degradation efficiency for acid orange 7 (AO7) was 100% within 20 min, while those for methyl orange (MO), methylene blue, and rhodamine B dyes were 97, 78, and 72%, respectively, within 40 min under ultrasonic vibration only. Furthermore, high catalytic efficiency of 96% was still maintained for AO7 degradation after 10 consecutive degradation cycles for samarium-doped 0.70Pb­(Mg1/3Nb2/3)­O3-0.30PbTiO3 due to its high piezoelectric coefficient. The investigation of the catalytic mechanism demonstrated that hole and superoxide radicals were the primary active species toward AO7 degradation, whereas hydroxyl and hole radicals were for MO degradation. This work not only demonstrates the highly efficient catalytic activity of samarium-doped (1 – x)­Pb­(Mg1/3Nb2/3)­O3-xPbTiO3 nanostructures but also gives a deep comprehension of the correlation between the piezoelectric property and catalytic performance of piezocatalysts.

Bi5Ti3FeO15 Nanofibers for Highly Efficient Piezocatalytic Degradation of Mixed Dyes and Antibiotics

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Piezoelectrically Mediated Reactions: From Catalytic Reactions to Organic Transformations

“…Atoms or ion doping attains much attention due to their higher piezocatalytic performance. [ 99 ] It is well known that the dielectric constant is an important indicator to characterize the piezoelectric activity of materials. The addition of metal atoms or ions…”

In situTEM observations of growth mechanisms of PbO nanoparticles from a Sm-doped PMN-PT matrix

“…(1 − x )Pb(Mg 1/3 Nb 2/3 )O 3 - x PbTiO 3 (PMN-PT) piezoelectric materials have attracted intensive research interest due to their excellent piezoelectric properties, 1–4 and can be widely applied in underwater acoustic transducers, energy harvesting, magneto-electric information storage devices and piezocatalysis. 5–9 Such lead-based piezoelectric materials can be prepared by sol–gel, 10 pulsed laser deposition, and physical vapor deposition methods, and so on. 11,12 In many mentioned preparation method, it is known that PbO could volatilize when such lead-based piezoelectric materials are sintered at high temperature (>890 °C).…”