Graphene – a monolayer of carbon atoms arranged in a honeycomb network – has attracted significant attention owing to its outstanding electronic, optical, thermal and mechanical properties. Here, we explore the synthesis of graphene and its derivatives using different approaches ranging from chemical conversion to vapor-phase deposition.1-3 The promising properties together with the ease of processing and functionalization make graphene-based materials attractive for various applications ranging from sensors to transparent conducting electrodes.4-10 Furthermore, we introduce a facile, inexpensive, solid-state method for generating, patterning and electronic tuning of laser converted graphene (LCG). Circuits and complex designs are directly patterned onto various flexible substrates without masks, templates, post-processing, transferring techniques or metal catalysts. This simple technology may help in the realization of inexpensive all-carbon flexible electronic devices. A prototype NO2 gas sensor is demonstrated. Recently, graphene-based materials have proven to be promising for electrochemical energy storage. We will discuss the fabrication of inexpensive electrochemical energy storage devices that combine the energy density of batteries with the power performance of capacitors in a single device. This represents a significant advance in energy storage technology and may lead to a new generation of inexpensive energy storage devices. Additionally, the devices can maintain their excellent electrochemical attributes under high mechanical stress. Since this remarkable performance has yet to be realized in commercial devices, these supercapacitors may be ideal for flexible portable electronics.
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