Abstract

We report herein the photocatalytic activity of undoped carbon nanodots (CD) and phosphorus doped carbon nanodots (P-CD), which effectively degrades methylene blue (MB) dye under continuous irradiation of sunlight. The P-CD and CD were synthesized by the hydrothermal method using d-glucose anhydrous as the precursor. The morphological and structural characterization of P-CD was done using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). UV–Visible spectroscopic studies of CD and P-CD showed maximum optical absorption at 252 nm and 283 nm and interestingly P-CD exhibited an intense emission at 520 nm. The average radius of P-CD was found to be 2.19 nm. Use of P-CD and CD as photocatalysts in the degradation of methylene blue under direct sunlight irradiation yielded favourable results with a dye degradation rate of 0.02736 min⁻¹ (standard error 0.00612) in presence of P-CD and a rate of 0.01645 min⁻¹ (standard error 0.00342) in presence of CD. The self-degradation rate of MB was feeble compared to the rate of degradation with photocatalysts P-CD and CD.

中文翻译：

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无金属，磷掺杂的碳纳米点介导的亚甲基蓝的光催化还原

摘要

我们在这里报告未掺杂的碳纳米点（CD）和掺磷的碳纳米点（P-CD）的光催化活性，在连续不断的阳光照射下有效降解了亚甲基蓝（MB）染料。P-CD和CD是通过水热法使用d合成的-无水葡萄糖作为前体。使用透射电子显微镜（TEM），傅立叶变换红外光谱（FT-IR）和X射线光电子能谱（XPS）对P-CD进行了形态和结构表征。CD和P-CD的紫外可见光谱研究显示，在252 nm和283 nm处具有最大的光吸收，有趣的是P-CD在520 nm处显示出强烈的发射。发现P-CD的平均半径为2.19nm。使用P-CD和CD的直射阳光照射下于亚甲基蓝的降解光催化剂产生了有利的结果与0.02736 min的染料降解速率^-1在P-CD的存在（标准误差0.00612）和0.01645 min的速率^{- 1个}（存在CD）（标准错误0.00342）。与用光催化剂P-CD和CD降解的速率相比，MB的自降解速率微弱。