Effect of doping, substrate, and annealing temperature on the photocurrent of graphene‐based photodetectors. a) Photocurrent transients of rGO and N‐rGO films under 3.0 mW cm−2 white‐light illumination. Reproduced with permission.[
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] Copyright 2015, Elsevier Ltd. b) Photograph and the cross‐sectional FESEM images of the N‐rGO photodetector devices on an 8 in. oxide silicon wafer. Reproduced with permission.[
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] Copyright 2019, American Chemical Society. c) Sulphur‐doped graphene QD (S‐GQD) photodetector for ultraviolet detection. i) Schematic of the synthesis of S‐GQDs. ii) Photoresponsivity of the S‐GQD/poly(9‐vinylcarbazole) (PVK) hybrid photodetector. Inset: The schematic diagram of the PVK/S‐GQD hybrid UV photodetector. Reproduced with permission.[
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] Copyright 2017, Royal Society of Chemistry. d) Photoresponse transients of the substrate‐free rGO photodetectors under 375, 532, and 1064 nm illumination. Reproduced with permission.[
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] Copyright 2017, Royal Society of Chemistry. e) Photocurrent transients of suspended rGO photodetectors after subjected to varying annealing temperatures under laser illumination of 375, 405, 532, 785, and 1064 nm at a bias voltage of 0.5 V. Reproduced with permission.[
75
] Copyright 2017, American Chemical Society.