Barbhuiya Najmul Haque, Nair Akhila M, Dixit Nandini, Singh Swatantra P
Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai 400076, India.
Centre for Research in Nanotechnology & Science (CRNTS), Indian Institute of Technology Bombay, Mumbai 400076, India.
ACS Omega. 2024 May 13;9(21):22819-22830. doi: 10.1021/acsomega.4c00959. eCollection 2024 May 28.
Laser-induced graphene (LIG) has garnered much attention due to its facile and chemically free fabrication technique. Metal nanoparticle incorporation into the LIG matrix can improve its electrical and catalytical properties for environmental application. Here, we demonstrate the fabrication of nanoscale zerovalent iron (nZVI) nanoparticle-incorporated LIG (Fe-LIG) and sulfidized-nanoscale zerovalent iron (S-nZVI) nanoparticle-incorporated LIG (SFe-LIG) surfaces. The sheets were first fabricated to investigate nanoparticle loading, successful incorporation in the LIG matrix, and electrochemical performance as electrodes. Fe-LIG and SFe-LIG sheets showed ∼3-3.5 times more charge density as compared with the control LIG sheet. The XPS and its deconvolution confirmed the presence of nZVI and S-nZVI in the Fe-LIG and SFe-LIG surfaces, which can generate hydroxyl radical (•OH) via iron activation of electrogenerated hydrogen peroxide (HO) in short electro-Fenton process. After confirmation of the successful incorporation of iron-based nanoparticles in the LIG matrix, filters were fabricated to demonstrate the application in the flow-through filtration. The Fe-LIG and SFe-LIG filters showed ∼10-30% enhanced methylene blue removal under the application of 2.5 V at ∼1000 LMH flux. The Fe-LIG and SFe-LIG filters also showed complete 6-log bacteria and virus removal at 2.5 and 5 V, respectively, while the LIG filters showed only ∼4-log removal. Such enhanced removal by the Fe-LIG and SFe-LIG filters as compared to LIG filters is attributed to the improved charge density, electrochemical activity, and electro-Fenton process. The study shows the potential to develop catalytic LIG-based surfaces for various applications, including contaminant removal and microbial inactivation.
激光诱导石墨烯（LIG）因其简便且无需化学处理的制备技术而备受关注。将金属纳米颗粒掺入LIG基质中可改善其电学和催化性能，以用于环境应用。在此，我们展示了掺入纳米级零价铁（nZVI）纳米颗粒的LIG（Fe-LIG）和掺入硫化纳米级零价铁（S-nZVI）纳米颗粒的LIG（SFe-LIG）表面的制备。首先制备这些薄片，以研究纳米颗粒负载、在LIG基质中的成功掺入以及作为电极的电化学性能。与对照LIG薄片相比，Fe-LIG和SFe-LIG薄片的电荷密度高出约3 - 3.5倍。X射线光电子能谱（XPS）及其去卷积证实了Fe-LIG和SFe-LIG表面存在nZVI和S-nZVI，它们可在短程电芬顿过程中通过铁对电生成的过氧化氢（HO）的活化产生羟基自由基（•OH）。在确认铁基纳米颗粒成功掺入LIG基质后，制备了过滤器以展示其在流通过滤中的应用。在约1000 LMH通量下施加2.5 V电压时，Fe-LIG和SFe-LIG过滤器对亚甲基蓝的去除率提高了约10 - 30%。Fe-LIG和SFe-LIG过滤器在2.5 V和5 V电压下分别还能完全去除6个对数级的细菌和病毒，而LIG过滤器仅能去除约4个对数级。与LIG过滤器相比，Fe-LIG和SFe-LIG过滤器的这种增强去除效果归因于电荷密度、电化学活性和电芬顿过程的改善。该研究表明开发基于LIG的催化表面用于各种应用（包括污染物去除和微生物灭活）的潜力。
