矽化物SrSi2被探知是具有非常窄的贗能隙之半金屬，其能隙大約35meV。在之前的研究就發現正向的化學壓力會對SrSi2的熱電性質造成有效的改變1。在本實驗中，我們透過量測Sr1-xCaxSi2和Sr1-xBaxSi2的電阻率、熱傳導率和Seebeck coefficient去說明化學壓力效應對其熱電性質和熱電優值的影響。我們發現SrSi2在室溫的電阻率和熱傳導率都會隨著Ca和Ba取代Sr的位置而些微變小，此外Seebeck coefficient在室溫時也有大幅的提升，這些影響導致其ZT值相對於沒摻雜的SrSi2能更有效的提升。Sr1-xBaxSi2系列樣品中Sr0.93 Ba0.07Si2在室溫時擁有最高的ZT值大約0.11，而Sr1-xCaxSi2系列樣品中Sr0.9Ca0.08Si2在室溫時擁有最高ZT值約為0.17.

Strontium disilicide SrSi2 has been recognized as a semimetal with a very narrow pseudogap of about 35 meV. Previous studies already indicated that the thermoelectric performance of SrSi2 could be effectively improved via chemical substitution1. In this investigation, we report the results of the temperature-dependent electrical resistivity, thermal conductivity, and Seebeck coefficient in Sr1-xBaxSi2 and Sr1-xCaxSi2 alloys to elucidate the chemical pressure effect on the thermoelectric performance, characterized by the figure-of-merit, ZT. It is found that the room-temperature electrical resistivities and thermal conductivities slightly reduce through the substitutions of Ba and Ca onto the Sr sites of SrSi2. Moreover, the room-temperature Seebeck coefficient are substantially enhanced. These promising effects lead to a significant enhancement in the ZT value as compared to stoichiometric SrSi2. Namely, the highest room-temperature ZT values of 0.11 and 0.17 for Sr0.93 Ba0.07Si2 and Sr0.92Ca0.08Si2, respectively were obtained.

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