Ultrafine α-Fe₂O₃ nanocrystals anchored on N-doped graphene: a nanomaterial with long hole diffusion length and efficient visible light-excited charge separation for use in photoelectrochemical sensing

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• 作者：Liming Dai ; Xiaojiao Du ; Ding Jiang ; Wei Chen ; Mingyue Zhu ; Kun Wang
• 关键词：Photoelectrochemical activity ; Visible ; light photoexcitation ; N ; doped graphene nanocomposite ; α ; Fe2O3 nanocrystals ; Charge separation
• 刊名：Microchimica Acta
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：184
• 期：1
• 页码：137-145
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Nanochemistry; Nanotechnology; Characterization and Evaluation of Materials; Analytical Chemistry; Microengineering;
• 出版者：Springer Vienna
• ISSN：1436-5073
• 卷排序：184

文摘

The authors have coupled ultrafine α-Fe₂O₃ nanocrystals to N-doped graphene (NG) to obtain a novel material for use in a photoelectrode. The presence of NG is shown to strongly affect the morphology and size of the α-Fe₂O₃ nanocrystals formed on the NG sheets, and to improve their photoelectrochemical (PEC) activity. Interestingly, the PEC performance of the nanocomposite is closely correlated to the size of the α-Fe₂O₃ nanocrystals in that small nanocrystals display better PEC properties. The photocurrent of α-Fe₂O₃-NG is nearly 3.3-fold stronger than that of α-Fe₂O₃ nanocrystals. Based on the remarkable PEC performance of this nanocomposite, a PEC sensor was constructed for the sensitive determination of 1,4-dihydroxybenzene (HQ). Its photocurrent increases with the HQ concentration in the range from 3.0 nM to 3.3 μM, and the detection limit is 1.0 nM (at an S/N ratio of 3). In our perception, the study presented here can serve as a basis for a better understanding of the relationship between morphologies and PEC performance of such nanomaterials. Conceivably, it may be extended to other PEC sensing system and to other fields associated with nanotechnology.