Abstract Theoretical chemists have predicted that Ti2CO2 and Ti3C2O2 possess an indirect bandgap that causes them to transform into semiconductors. However, few experiments have reported the appropriate bandgap for Ti3C2O2 and Ti2CO2. In this study, we first proved that Ti3C2O2 is a semiconductor by using a base-assisted intercalation method. A comprehensive study, including spectroscopy measurements, a computational approach, and mechanism analysis, established the efficacy of using a base. Results showed that Ti3C2O2 with a bandgap of 0.66 eV can be easily obtained after low-temperature annealing by using a novel base-assisted intercalation method. By contrast, such compound was hardly obtained when a solution intercalation procedure was used. The significant effect of the base was demonstrated in the synthesis procedure and the mechanism. The theoretical calculation predicted that Ti3C2O2 is a semiconductor with an indirect bandgap of 0.63 eV from the generalized gradient approximation. This prediction is consistent with the experimentally determined value.

中文翻译：

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碱辅助插层在二维半导体 Ti3C2O2 合成中的显着影响

摘要 理论化学家预测，Ti2CO2 和 Ti3C2O2 具有间接带隙，导致它们转变为半导体。然而，很少有实验报告了 Ti3C2O2 和 Ti2CO2 的合适带隙。在这项研究中，我们首先通过使用碱辅助插层方法证明了 Ti3C2O2 是一种半导体。一项综合研究，包括光谱测量、计算方法和机制分析，确定了使用碱的功效。结果表明，通过使用新型碱辅助插层方法，低温退火后可以很容易地获得带隙为 0.66 eV 的 Ti3C2O2。相比之下，当使用溶液嵌入程序时，很难获得这种化合物。在合成过程和机理中证明了碱的显着影响。理论计算预测 Ti3C2O2 是一种间接带隙为 0.63 eV 的半导体，从广义梯度近似。该预测与实验确定的值一致。