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Perovskite-type manganite-based ceramics is a promising thermoelectric material at high temperature, while the poor electrical resistivity and thermal conductivity restrict the application in area of thermoelectricity generators. Entropy engineering can...

Achieving high thermoelectric properties of CaMnO3 ceramics is significant for its applications at high temperature. Herein, Ca0.87Ag0.1Dy0.03MnO3 ceramics with plate-like template seeds additives were prepared by using a solid-state reaction method. The multiscale defects, including grain boundaries, oxygen defects, and Ag nanoprecipitations, which were regulated by the different sintering atmospheres, were beneficial for electron transport and phonon scattering. The grain boundaries as coherent interfaces could act as an alternative phonon scattering source. Oxygen vacancies coupled with Ag nanoprecipitations were verified by geometric phase analysis and annular bright-field analysis. The decrement in oxygen vacancies concentration strongly depended on the enriched oxygen environment, which could reduce electrical resistivities. Compared to the sample sintered at Ar atmosphere, a 17.5 times increment in power factor and a 20.1% reduction of the total thermal conductivity were obtained for the sample sintered at O2 atmosphere. As a result, the maximum ZT value of 0.22 was obtained at 500 °C. It is an effective way for improving the thermoelectric performance of oxide-based thermoelectric materials.

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Lithium–sulfur batteries, due to their various advantages such as their unique theoretical capacity, inexpensive, and environmental friendliness, have become one of the new‐generation energy storage systems. However, during the commercial development of lithium–sulfur batteries, they are limited by obstacles such as the volume expansion, shuttle effect, and low conductivity of S, which eventually lead to slow system reaction kinetics and poor cycling stability. Herein, heterostructured metal–organic framework‐derived Co3O4/TiO2 hybrids have been designed. The hollow structure of the Co3O4 is coupled with TiO2 on the surface to form a heterojunction to construct an internal electric field, which can promote charge transfer and improve reaction kinetics. Meanwhile, Co3O4/TiO2 has excellent trapping ability for lithium polysulfide, reducing the shuttle effect and alleviating volume expansion. As the cathode material, the initial discharge capacity of S@Co3O4/TiO2 at 0.1C is 1152.7 mAh g−1. Meanwhile, it has an initial specific capacity of 657 mAh g−1 at 1C, a capacity retention rate of 63.7% after 500 charge/discharge cycles, and an effective cycling stability with a decay rate of 0.072% in each cycle. This indicates that the construction of heterojunctions between materials has some enhancement on the performance of Li–S batteries.