A novel porous La₂Zr₂O₇ ceramic aerogels with ultralow thermal conductivity and photocatalytic property

Abstract

Porous La 2 Zr 2 O 7 ceramic aerogels (CAs) were prepared by sol-gel template method and thermal treated process. The microstructure and crystallisation behavior of the samples were systematically characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy. The results indicated that the asprepared porous La 2 Zr 2 O 7 CAs had a single-phase pyrochlore structure with typical three-dimensional (3-D) porous structure. Meanwhile, the formation mechanisms of the as-prepared porous La 2 Zr 2 O 7 CAs were investigated. At the same time, the as-prepared porous La 2 Zr 2 O 7 CAs presented an ultralow roomtemperature thermal conductivity of 0.07 W/(m K), high specific surface areas of 325.17 m 2 /g, and a relatively high compressive strength of 11.95 MPa. What's more, the as-prepared porous La 2 Zr 2 O 7 CAs possessed ideal photocatalytic activities due to its high crystallinity, large surface area as well as unique 3-D porous structure. Therefore, the present work is proposing some new insight to prepare rare-earth zirconates CAs with porous structures for thermal insulation and dye degradation applications. K E Y W O R D Sceramic aerogels, La 2 Zr 2 O 7 , photocatalytic, sol-gel template method, thermal conductivity 1 2772

Synergistic Interaction of MoS2 Nanoflakes on La2Zr2O7 Nanofibers for Improving Photoelectrochemical Nitrogen Reduction

“…Pan and co-workers observed that the defect-to-ordered phase structure in La 2 Zr 2 O 7 occurs at 875 °C when the material contains both fluorite and pyrochlore structures. The heterostructure formation is found to produce an increased surface area and varied grain boundaries that make it a budding choice for electrocatalytic applications. ,, …”

“…The heterostructure formation is found to produce an increased surface area and varied grain boundaries that make it a budding choice for electrocatalytic applications. 14,45,46 In this study, we designed a novel heterostructure of 2D-MoS 2 nanoflakes assembled on a mixed phase of La 2 Zr 2 O 7 nanofibers (MoS 2 @LZO), which exhibits outstanding PEC-NRR activity. MoS 2 -coated La 2 Zr 2 O 7 heterostructures (MoS 2 @LZO) are synthesized via a facile hydrothermal technique at 220 °C for 24 h using Na 2 MoO 4 •2H 2 O as the Mo source and C 2 H 5 NS as the S source with calcined La 2 Zr 2 O 7 electrospun nanofibers (LZO) as a substrate/ template.…”