Transient features of graphene oxide (GO), graphene oxide nanoribbon (GOR) and graphene quantum dot (GQD) have been investigated by femtosecond transient absorption (TA) spectroscopy. It is found that for pristine GO and HNO₃-/NaOH-treated GO, a hybrid sp²/sp³ state at about 430 nm (∼2.88 eV) always appears. However, this hybrid state becomes less apparent in GOR, and completely disappears in GQD. It indicates that there are absolutely different electronic structures in GO, GOR and GQD. Furthermore, compared with pristine GO and GQD, GOR presents a faster decay for carrier dynamics. This could be attributed to the relatively weak interaction between the sp² domains and sp³ matrix in GOR, which facilitates the carrier recombination.

中文翻译：

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氧化石墨烯、氧化石墨烯纳米带和石墨烯量子点电子结构的飞秒瞬态吸收光谱研究

已经通过飞秒瞬态吸收 (TA) 光谱研究了氧化石墨烯 (GO)、氧化石墨烯纳米带 (GOR) 和石墨烯量子点 (GQD) 的瞬态特征。发现对于原始的 GO 和 HNO ₃ -/NaOH 处理的 GO，在大约 430 nm (~2.88 eV) 处总是出现混合 sp ² /sp ³状态。然而，这种混合状态在 GOR 中变得不那么明显，在 GQD 中完全消失。这表明 GO、GOR 和 GQD 中存在绝对不同的电子结构。此外，与原始 GO 和 GQD 相比，GOR 呈现出更快的载流子动力学衰减。这可能归因于 sp ²域和 sp ³之间相对较弱的相互作用 GOR 中的矩阵，这有利于载体重组。