ZnCl活化的氧化石墨烯和纳米多孔石墨烯对挥发性有机化合物的优化吸附：实验与计算相结合的研究

Optimized adsorption of volatile organic compounds on graphene oxide and nanoporous graphene activated with ZnCl: a combined experimental and computational study.

作者信息

Zafari Tahereh, Sharafinia Soheila, Rashidi Alimorad, Esrafili Mehdi D, Keyvani Bahram, Mousavi Mohsen

机构信息

Department of Chemical Engineering, Saveh Islamic Azad University Iran.

Department of Chemistry, Faculty of Science, Shahid Chamran University of Ahvaz Ahvaz Iran.

出版信息

Nanoscale Adv. 2025 Aug 28. doi: 10.1039/d5na00199d.

DOI:10.1039/d5na00199d

PMID:40895585

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC12394901/

Abstract

The present research is a comparison study of adsorption capacity of graphene oxide (GO) and nanoporous graphene (NPG) for volatile organic compounds' vapor (here gasoline vapor) adsorption. GO was synthesized using the modified Hummers method. For the synthesis of NPG, a low-cost precursor with unique properties (camphor) was used by the chemical vapor deposition (CVD) method. The effect of reaction temperature parameter, the ratio of camphor to zinc oxide nanocatalyst and reaction time was investigated. The physicochemical properties of the samples were characterized using XRD, FT-IR, Raman, FE-SEM, TEM and BET techniques. It was observed that activation by ZnCl at 600 °C and 180 min ( NPG2) gives a surface area of 181.61 m g. NPG2 showed high adsorption capacity for VOC adsorption (559 mg g), which was about 1.34-2.58 times more than other synthesized samples (adsorption capacities of PG1, PG3, GO1, GO2, and GO3 were 415, 310, 300, 367, and 216 mg. g, respectively). The high VOC adsorption capacity of PG was due to its π-π interactions with the NPG surface. Therefore, the NPG2 sample was selected as the best sample. In general, all synthesized samples showed rapid kinetic behaviors for gasoline vapor adsorption, and their maximum adsorption capacity was obtained in the first 35 min. To shed insight on the adsorption process of gasoline on NPG and GO, density functional theory (DFT) calculations were performed. According to the DFT calculations, the adsorption strength of an isobutane (ISO) molecule improved as the pore size on the NPG increased. The adsorption energy of ISO on GO was less than that on NPG, most likely due to steric repulsion between the ISO and O moieties on the GO. The negative enthalpy and Gibbs free energy changes caused by ISO adsorption on NPG and GO showed that the process is thermodynamically favorable at room temperature and pressure.

摘要

本研究是一项关于氧化石墨烯（GO）和纳米多孔石墨烯（NPG）对挥发性有机化合物蒸汽（此处为汽油蒸汽）吸附容量的比较研究。采用改进的Hummers法合成GO。对于NPG的合成，通过化学气相沉积（CVD）法使用了具有独特性质的低成本前驱体（樟脑）。研究了反应温度参数、樟脑与氧化锌纳米催化剂的比例以及反应时间的影响。使用XRD、FT-IR、拉曼、FE-SEM、TEM和BET技术对样品的物理化学性质进行了表征。观察到在600℃和180分钟（NPG2）下用ZnCl活化得到的比表面积为181.61 m²/g。NPG2对VOC吸附显示出高吸附容量（559 mg/g），比其他合成样品高约1.34 - 2.58倍（PG1、PG3、GO1、GO2和GO3的吸附容量分别为415、310、300、367和216 mg/g）。PG对VOC的高吸附容量归因于其与NPG表面的π-π相互作用。因此，选择NPG2样品作为最佳样品。总体而言，所有合成样品对汽油蒸汽吸附均表现出快速动力学行为，且在最初35分钟内获得最大吸附容量。为深入了解汽油在NPG和GO上的吸附过程，进行了密度泛函理论（DFT）计算。根据DFT计算，随着NPG上孔径增大，异丁烷（ISO）分子的吸附强度提高。ISO在GO上的吸附能小于在NPG上的吸附能，很可能是由于ISO与GO上的O部分之间的空间排斥。ISO在NPG和GO上吸附引起的负焓变和吉布斯自由能变化表明该过程在室温和常压下在热力学上是有利的。