Differentiating structure of in situ and ex situ formation of laser-induced graphene hybrids

Laser-induced graphene (LIG) has been exploited in various fields, such as batteries, water treatment, and flexible actuators and sensors, with the advantages of ease in patternable fabrication and graphene/metal hybrid preparation. The in situ method which includes a single lase step and the ex situ method which uses two lase steps are both widely implemented to synthesize graphene/metal hybrids. However, the differences in the structures and properties of the resulting hybrids are not fully understood. Here, we investigate the advantages of ex situ and in situ methods for preparing LIG hybrids using NiFe/LIG as an example. The morphology, elemental composition, resistance to strong acid, and application in electrocatalysis and dye adsorption of ex situ and in situ NiFe/LIG hybrids were systematically studied and compared. Energy-dispersive X-ray spectrometry (EDS) and vibrating sample magnetometry (VSM) results confirmed the structural differences between the NiFe/LIG hybrids. Metal nanoparticles are mostly wrapped by carbon layers in the in situ NiFe/LIG hybrid, while the ex situ NiFe/LIG hybrid largely exposes the metal nanoparticles. These structural differences are significant for tailoring performance in applications, such as wastewater treatment and electrocatalysis. This work provides insights into the synthesis and properties of LIGs and has important implications for future applications.

激光誘導石墨烯(LIG)具有易於圖形化製造和石墨烯/金屬複合製備的優點, 已被廣泛應用於電池、水處理、柔性驅動器和傳感器等領域。原位法和非原位法均被廣泛用於合成石墨烯/金屬複合物。然而, 由這兩種方法所產生的複合材料在結構和性質上的差異尚未清楚。本文以NiFe/LIG為例, 研究了非原位和原位方法製備石墨烯和金屬複合物的優勢。系統地研究和比較了原位和非原位NiFe/LIG複合物的形貌、元素組成、耐酸性以及在電催化和染料吸附方面的應用。能量色散X射線光譜 (EDS) 和振動樣品磁強計 (VSM) 的結果證實了NiFe/LIG雜化物之間的結構差異。在原位NiFe/LIG中, 金屬納米粒子主要被碳層包裹, 而非原位NiFe/LIG則暴露出大部分的金屬納米粒子。這些結構差異對於廢水處理和電催化等特定應用中的性能顯得非常重要。這項工作為LIG的合成和性質提供了一定的研究基礎, 並對未來的應用具有重要意義。