(東北大學(xué) 材料與冶金學(xué)院， 沈陽(yáng) 110004)
摘 要: 用溶膠-凝膠法制備了NaCo2O4及(Na1-yMy)1.6Co2O4(M=K, 0.05≤y≤0.35; M= Ca, Sr, 0.10≤y≤0.40)的氧化物。 研究結(jié)果表明: 摻雜Ca、 Sr的NaCo2O4樣品的Seebeck系數(shù)都有一定提高； 而摻雜K的NaCo2O4樣品的Seebeck系數(shù)無明顯提高， 且摻K使NaCo2O4的功率因子降低； 對(duì)NaCo2O4摻雜Ca的量0＜y＜0.30時(shí)， 功率因子有所提高， 在y＝0.1時(shí)， 功率因子最大為1.68×10-4 W·m-1·K-2， 比摻雜前提高11％； 當(dāng)Sr摻雜量y＝0.1時(shí)， 功率因子的極大值為2.26×10-4 W·m-1·K-2， 比摻雜前提高50％。 摻雜金屬Sr的NaCo2O4材料熱電性能效果最好， 實(shí)驗(yàn)結(jié)果說明選擇合適的元素及最佳的摻雜量進(jìn)行摻雜能大大提高氧化物材料NaCo2O4的熱電性能。
關(guān)鍵字: 熱電材料； 電學(xué)性能； 溶膠-凝膠法； 摻雜； NaCo2O4； Seebeck系數(shù)
(Na1-yMy)1.6Co2O4(M=K, Ca, Sr)
（ School of Materials and Metallurgy, Northeastern University,
Shenyang 110004, China）
Abstract: NaCo2O4 and (Na1-yMy)1.6Co2O4(M=K, 0.05≤y≤0.35; M= Ca, Sr, 0.10≤y≤0.40) is synthesized by the sol-gel method. The results show that Seebeck coefficient of NaCo2O4 is increased by doping with Ca and Sr but K, and its power factor is reduced by doping with K and increased by doping with Ca (0＜y＜0.30), and the power factor is at its maximum value of 1.68×10-4 W·m-1·K-2 by doping with Ca (y=0.1) and increased 11% compared with that without doping elements. The maximum value of power factor is 2.26×10-4 W·m-1·K-2 in case by doping with Sr (y=0.1) and is increased by 50% compared with that without doping with Sr. The thermoelectric property of NaCo2O4 after doping with Sr is the best. The experimental results show that the appropriate doping elements and doping amount can improve consumedly the thermoelectric properties of NaCo2O4.
Key words: thermoelectric materials; electric properties; sol-gel method; doping; NaCo2O4; Seebeck coefficient
