Bulk amorphous materials have been studied extensively and are used widely. Yet, their atomic arrangement remains an open issue. They are generally believed to be Zachariasen continuous random networks (Z-CRNs) 1 , but recent experimental evidence favours the competing crystallite model in the case of amorphous silicon 2-4 .Corresponding questions in 2D materials are wide open. Here we report the synthesis of centimetre-scale, freestanding, continuous, and stable monolayer amorphous carbon (MAC), topologically distinct from disordered graphene, by laser-assisted chemical vapour deposition 5 . Unlike bulk materials, the amorphous structure of MAC can be determined by atomic-resolution imaging. Extensive characterisation reveals complete absence of long-range periodicity and a threefold-coordinated structure with a wide distribution of bond lengths, bond angles, and 5-, 6-, 7-, and 8-member rings. The ring distribution is not a Z-CRN but resembles the competing (nano)crystallite model 6 . A corresponding model has been constructed and enables density-functional-theory calculations of MAC properties, in accord with observations. Direct measurements

A graphene and zinc oxide nanowires (G/ZnO NWs) based ultraviolet (UV) photodetector presents excellent responsivity and photocurrent gain with detectivity. Graphene due to higher charge carrier transport mobility induces faster response to UV illumination at the interface between ZnO and graphene with improved response and decay times as compared to a ZnO NWs device alone. A linear increase is revealed for both the responsivity and photocurrent gain of the G/ZnO NWs device with the applied bias. These results suggest that the G/ZnO NWs device exhibits great promise for highly efficient UV photodetectors.

A novel approach is presented for achieving an enhanced photoresponse in a few layer graphene (FLG) based photodetector that is realized by introducing defect sites in the FLG. Fabrication induced wrinkle formation in graphene presented a four-fold enhancement in the photocurrent when compared to unfold FLG. Interestingly, it was observed that the addition of few multiwalled carbon nanotubes to an FLG improves the photocurrent by two-fold along with a highly stable response as compared to FLG alone.

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Recently, graphene has attracted much attention due to its unique electrical and thermal properties along with its high surface area, and hence presents an ideal sensing material. We report a novel configuration of a graphene based flame sensor by exploiting the response of few layer graphene to a flame along two different directions, where flame detection results from a difference in heat transfer mechanisms. A complete sensor module was developed with a signal conditioning circuit that compensates for any drift in the baseline of the sensor, along with a flame detection algorithm implemented in a microcontroller to detect the flame. A pre-defined threshold for either of the sensors is tunable, which can be varied based on the nature of the flame, hence presenting a system that can be used for detection of any kind of flame. This finding also presents a scalable method that opens avenues to modify complicated sensing schemes.