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In this paper, the Ca11.52Sr0.48Al14O33 + Ca2.88Sr0.12Al2O6 of a specific stoichiometric ratio is used as a precursor. The [Ca23.04Sr0.96Al28O64](4+)(4e(-)) electrides block with a high electron concentration successfully prepared by in-situ aluminothermic reaction using a spark plasma sintering system(SPS). The sintering temperature is 1050 degrees C, and the holding time is 5 min. The UV spectrophotometer results showed that (Ca0.96Sr0.04)12A7:e(-) showed the visible UV absorption peak at around 2.5 eV, and the electron concentration was calculated to reach 2.2 x 10(21) cm(-3). Simultaneously, the electronic structure is analyzed by a paramagnetic resonance spectrometer, and the result shows that electrons are injected uniformly in the sample. The synchronous thermal analyzer's results showed that (Ca0.96Sr0.04)12A7:e(-) weight loss occurred above 700 degrees C was derived from oxygen desorption. These results altogether demonstrate that electrons are efficiently injected into the cage structure of (Ca0.96Sr0.04)12A7:e(-). This process provides a new electron-injection method, which significantly shortens the preparation cycle of (Ca0.96Sr0.04)12A7:e(-) and makes mass production of samples possible. The electronic structure of (Ca0.96Sr0.04)12A7:e(-) calculated using first-principles. The results show a cage conduction band (CCB) between - 1 eV and 0.7 eV, which is favorable for electrical performance. The results also show that the excellent electrical transport performance of (Ca0.96Sr0.04)12A7:e(-) mainly comes from Sr, Ca atom s-state electrons, and Al atom p-state electrons. (C) 2021 Elsevier B.V. All rights reserved.
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