Using first-principles calculations, we studied the electronic, structural and thermoelectric properties of two-dimensional (2D) MXenes Mn+1CnO2 (M = Ti, Zr and Hf, n = 1, 2 and 3). The calculations are carried out within the generalized gradient approximation (GGA). We have calculated the Boltzmann transport equation for finding the thermoelectric properties such as power factor, Seebeck coefficient and electrical conductivity. For n = 1, these materials behave as semiconductors having an indirect bandgap nature. In contrast, for n > 1 these materials show metallic behavior. Out of these MXenes, we found that Ti₂CO₂ has a high Seebeck coefficient value, whereas the electrical conductivity of Ti₄C₃O₂ is exceptionally high. While among all these compounds, Ti₂CO₂ and Hf₄C₃O₂ have a high power factor in the 300–1200-K temperature range.

中文翻译：

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功能化 MXenes Mn+1CnO2（M = Ti、Zr 和 Hf，n = 1、2 和 3）的比较研究：可再生能源应用的建议

使用第一性原理计算，我们研究了二维 (2D) MXenes 的电子、结构和热电特性米n+1Cn○2(米= 钛、锆和铪，n = 1, 2 和 3)。计算在广义梯度近似 (GGA) 内进行。我们计算了玻尔兹曼输运方程，以求出功率因数、塞贝克系数和电导率等热电特性。为了n = 1，这些材料表现为具有间接带隙性质的半导体。相比之下，对于n > 1这些材料表现出金属行为。在这些 MXenes 中，我们发现 Ti ₂ CO _{2具有较高的塞贝克系数值，而 Ti 4} C ₃ O ₂的电导率异常高。而在所有这些化合物中，Ti ₂ CO ₂和 Hf ₄ C ₃ O ₂在 300–1200-K 温度范围内具有高功率因数。