Semiconductors as forms of printable ink. a) Top: chemical structure of the soluble DNTT precursor and its thermal conversion process. Bottom: Schematic illustration of the device structure of DNTT TFT. b) Sequential images of the process of printing seven metal layers. Scale bar, 1 mm. c) A photograph of the printed PVDF‐TrFE piezoelectric film. d) Schematic illustration of PVDF inks. e) Optical micrographs 3D‐printed single line pattern of organic semiconductors, and the multilayer printing. Scale bars, 10 µm and 100 µm, respectively. f) Schematic illustration showing the design of thermoelectric ink. g) Photograph and illustrated premodels of arch‐type architectures consisting of junctional p‐ and n‐type inorganic semiconductors. Scale bar, 500 µm. h) Top: photograph of CNF‐containing inks and pure LiFePO4 (LFP) dispersion ink, Bottom: photograph of 3D‐printed CNF/LFP structure. i) Top: schematic illustration showing 3D printing of halide perovskites. Bottom: optical micrographs showing the 3D printing processes. Scale bar, 10 µm. j) Optical micrographs of rGO TFTs. Scale bars, 200 µm and 30 µm, respectively. k) Cross‐sectional SEM of printed CNT TFT. Inset: magnified SEM of printed CNT layer. l) Schematic illustration and photographs of printed Mxene ink. a) Reproduced with permission.[
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] Copyright 2015, Wiley‐VCH. b) Reproduced with permission.[
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] Copyright 2019, Springer Nature. c) Reproduced with permission.[
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] Copyright 2021, Elsevier. d) Reproduced with permission.[
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] Copyright 2021, American Chemical Society. e) Reproduced under the terms of the Creative Commons CC‐BY license.[
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] Copyright 2019, The Authors. Published by Wiley‐VCH. f,g) Reproduced with permission.[
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] Copyright 2021, Springer Nature. h) Reproduced with permission.[
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] Copyright 2019, Wiley‐VCH. i) Reproduced with permission.[
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] Copyright 2019, Wiley‐VCH. j) Reproduced with permission.[
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] Copyright 2015, Wiley‐VCH. k) Reproduced with permission.[
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] Copyright 2020, Wiley‐VCH. l) Reproduced with permission.[
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] Copyright 2019, Springer Nature.