direct laser scribing with a commercial CO 2 infrared laser system as found in most machine shops, the product being termed laser-induced graphene (LIG). [15] LIG exhibits high surface area (≈340 m 2 g −1 ), high thermal stability (>900 °C), and excellent conductivity (5-25 S cm −1 ). [15] The entire process can be performed in ambient air without any solvents, thereby making it exceedingly attractive for industrial use. This protocol combines the 3D graphene synthesis with writing into a single step process that has stimulated research ranging from fundamental studies on the transformation process to the development of a large variety of engineering applications. [15][16][17][18][19][20][21][22] Here, starting from the discovery of LIG, we will first emphasize strategies for the engineering of chemical, physical, and electronic properties of LIG; specifically, the regulation of laser parameters, atmosphere, and substrates to control the porosity, composition, and morphology of the LIG. The controllable synthesis of LIG and ease in property engineering makes it a versatile material in various applications including in sustainable energy conversions such as water splitting and fuel cell technology, [20,23] supercapacitors (SCs) for energy storage, [15,16,[24][25][26] sensors for sound, photon, strain, and chemicals detection, [27][28][29][30][31][32][33] and microfluidics [34][35][36] that are applicable to the laboratory and industrial scales, as outlined. Finally, the future advancement, such as the development of flexible electronics and biodegradable devices, will be discussed.Laser-induced graphene (LIG) is a 3D porous material prepared by direct laser writing with a CO 2 laser on carbon materials in ambient atmosphere. This technique combines 3D graphene preparation and patterning into a single step without the need for wet chemical steps. Since its discovery in 2014, LIG has attracted broad research interest, with several papers being published per month using this approach. These serve to delineate the mechanism of the LIG-forming process and to showcase the translation into many application areas. Herein, the strategies that have been developed to synthesize LIG are summarized, including the control of LIG properties such as porosity, composition, and surface characteristics, and the advancement in methodology to convert diverse carbon precursors into LIG. Taking advantage of the LIG properties, the applications of LIG in broad fields, such as microfluidics, sensors, and electrocatalysts, are highlighted. Finally, future development in biodegradable and biocompatible materials is briefly discussed. Laser-Induced Graphene

Research on graphene abounds, from fundamental science to device applications. In pursuit of complementary morphologies, formation of graphene foams is often preferred over the native two-dimensional (2D) forms due to the higher available area. Graphene foams have been successfully prepared by several routes including chemical vapor deposition (CVD) methods and by wet-chemical approaches. For these methods, one often needs either high temperature furnaces and highly pure gases or large amounts of strong acids and oxidants. In 2014, using a commercial laser scribing system as found in most machine shops, a direct lasing of polyimide (PI) plastic films in the air converted the PI into 3D porous graphene, a material termed laser-induced graphene (LIG). This is a one-step method without the need for high-temperature reaction conditions, solvent, or subsequent treatments, and it affords graphene with many five-and seven-membered rings. With such an atomic arrangement, one might call LIG "kinetic graphene" since there is no annealing in the process that causes the rearrangement to the preferred all-six-membered-ring form. In this Account, we will first introduce the approaches that have been developed for making LIG and to control the morphology as either porous sheets or fibrils, and to control porosity, composition, and surface properties. The surfaces can be varied from being either superhydrophilic with a 0° contact angle with water to being superhydrophobic having >150° contact angle with water. While it was initially thought that the LIG process could only be performed on PI, it was later shown that a host of other polymeric substrates, nonpolymers, metal/plastic composites, and biodegradable and naturally occurring materials and foods could be used as platforms for generating LIG. Methods of preparation include roll-to-roll production for fabrication of in-plane electronics and two different 3D printing (additive manufacturing) routes to specific shapes of LIG monoliths using both laminated object manufacturing and powder bed fabrication methods. Use of the LIG in devices is performed very simply. This is showcased with high performance supercapacitors, fuel cell materials for oxygen reduction reactions, water splitting for both hydrogen and oxygen evolution reactions coming from the same plastic sheet, sensor devices, oil/water purification platforms, and finally applications in both passive and active biofilm inhibitors. So the ease of formation of LIG, its simple scale-up, and its utility for a range of applications highlights the easy transition of this substrate-bound graphene foam into commercial device platforms.

Recent research has focused upon the growth of the graphene, with a concentration on the synthesis of graphene and related materials using both solution processes and high temperature chemical vapor and solid growth methods. Protocols to prepare high aspect ratio graphene nanoribbons from multi-walled carbon nanotubes have been developed as well as techniques to grow high quality graphene for electronics and other applications where high quality is needed. Graphene materials have been manipulated and modified for use in applications such as transparent electrodes, field effect transistors, thin film transistors and energy storage devices. This review summarizes the development of graphene and related materials.

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This paper reviews the various methods used to measure the electrical characteristics of individual or small groups of molecules, including crossed-wire junctions, mechanically controllable break junctions, conducting atomic force microscopy, scanning tunneling microscopy, molecular electronics on silicon surfaces, the NanoCell, nanopores, and other devices. It is shown that in the most common embodiment, the metal-molecule-metal junction, the assembly must be considered in whole. The characteristics of the molecule cannot be easily separated from the metal electrodes connected to it or from the method used to do the testing. I(V,T) data is necessary to rule out non-molecular transport mechanisms such as metal filament formation.