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Structural mosaic of rare-earth tri-tellurides (RTe3) inlaid with non-classical structural motifs like the 2D-polytelluride square nets has attracted immense attention owing to their enigmatic chemical bonding, unconventional structure, and harboring charge density wave (CDW) ground states. GdTe3, an archetypal RTe3, is a natural heterostructure of charged and van der Waals (vdW) layers, formed by intercalating vdW gap separated 2D square telluride nets … between the charged double corrugated slabs of n[GdTe]+. Here, we have investigated the evolution of structural distortions along with the electrical and thermal transport properties of GdTe3 across its CDW transition through X-ray pair distribution function analysis, thermal conductivity measurements, Raman spectroscopy and first principles theoretical calculations. The results reveal that the unusual structure of GdTe3 engenders a large anisotropic lattice thermal conductivity by concomitantly hampering the phonon propagation along parallel to the spark plasma sintering (SPS) pressing direction via chemical bonding hierarchy while facilitating phonon propagation along perpendicular to the SPS pressing direction through the metallic Te sheets and phason channel. The low lattice thermal conductivity is attributed to the strong vibrational anharmonicity caused by CDW-induced concerted local lattice distortions of both Gd-Te slab and Te square net, and the robust electron-phonon coupling. [ABSTRACT FROM AUTHOR]

Structural mosaic of rare-earth tri-tellurides (RTe3) inlaid with non-classical structural motifs like the 2D-polytelluride square nets has attracted immense attention owing to their enigmatic chemical bonding, unconventional structure, and harboring charge density wave (CDW) ground states. GdTe3, an archetypal RTe3, is a natural heterostructure of charged and van der Waals (vdW) layers, formed by intercalating vdW gap separated 2D square telluride nets … between the charged double corrugated slabs of n[GdTe]+. Here, we have investigated the evolution of structural distortions along with the electrical and thermal transport properties of GdTe3 across its CDW transition through X-ray pair distribution function analysis, thermal conductivity measurements, Raman spectroscopy and first principles theoretical calculations. The results reveal that the unusual structure of GdTe3 engenders a large anisotropic lattice thermal conductivity by concomitantly hampering the phonon propagation along parallel to the spark plasma sintering (SPS) pressing direction via chemical bonding hierarchy while facilitating phonon propagation along perpendicular to the SPS pressing direction through the metallic Te sheets and phason channel. The low lattice thermal conductivity is attributed to the strong vibrational anharmonicity caused by CDW-induced concerted local lattice distortions of both Gd-Te slab and Te square net, and the robust electron-phonon coupling. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 into value‐added chemicals is necessary to mitigate the increasing global warming and energy‐related issues. The selective production of C2 or C2+ products by photoreduction of CO2 is a challenging task due to the sluggish kinetics of C─C coupling. Herein, the potential of a silver nanoparticle (Ag NP) incorporated metal‐organic framework (MOF), NU‐1000 is introduced, to harvest light and ease the uphill electron transfer. The growth of silver nanoparticles on thiol‐functionalized NU‐1000 is studied using the atomic pair distribution function (PDF) analysis. The C2 product formed using Ag@NU‐1000‐SH without any sacrificial agents is acetic acid, which is confirmed by 1H‐NMR and HRMS data. The catalyst displays a high acetate output of 293.58 µmolg−1h−1 with a selectivity of 79.4%. The XPS and DFT calculations evidence that the presence of the charge‐polarised states in the as‐synthesized catalyst act as asymmetric centers that favor the C─C coupling reaction. The combined experimental (in situ DRIFT spectroscopic studies) and theoretical calculations reveal that the C─C coupling takes place via the coupling of COOH*intermediates. [ABSTRACT FROM AUTHOR]