Rollable, Stretchable, and Reconfigurable Graphene Hygroelectric Generators

Abstract

has been effectively utilized to generate considerable power, attracting the increasing attention because of the ubiquitous water molecules migration behavior in nature. [11][12][13][14][15] In this regard, we and others have designed and constructed various moisture-triggered electric generators to convert the chemical potential energy of moisture diffusion into useful electric energy. [14][15][16] The electricity generation process on these newly developed hygroelectric generator (HEG) devices is efficient and clean without much heat loss, mechanical movement, or byproduced pollutant. [10,16] However, the monotonous structure and poor mechanical properties of these devices have extremely restricted their portable applications in complex and mutable conditions. Meanwhile, the systematical integration of well-arranged generator units on a large scale is severely difficult and waiting for proper processing strategies. Graphene oxide (GO) possesses abundant oxygencontaining groups (e.g., COOH) and high specific surface area, allowing the excellent water molecules absorption between quasi-2D planar structures and generating substantial ionized protons under the hydration effect. [16][17][18][19][20][21] Gradient oxygen-containing groups can be constructed in GO materials by an electric polarization method developed in our previous studies, [16][17][18][19] which will induce inner ion concentration gradient and accordingly produce electricity under humidity variation. Moreover, the high mechanical tolerance and the ease of manufacturing of GO film could provide an ideal platform for construction of electricity generation device with special configuration. [15][16][17][18] Herein, we develop a series of rollable, stretchable, and even 3D space-deformable graphene-based HEG (GHEG) devices (Figure 1a) by laser processing strategy. Serial generator units have been directly embedded in the flexible GO film and exhibit excellent electricity generation ability without any significant performance loss despite being bent arbitrarily (Figure 1a,b). Strikingly, the serpentine or fractal bridge-island-structured GHEGs can power a light-emitting diode (LED) bulb in atmosphere under 100-2000% strain change (Figure 1c). Furthermore, 3D space-deformable architectures of GHEGs (Figure 1d) can be automatically assembled in the shapes of cubic boxes, pyramids, football, and even complex origami structures (Figure 1d,e). These deformable GHEGs will be promising for applications in many complicated conditions. Moisture-triggered electricity generation has attracted much attention because of the effective utilization of the water-molecule diffusion process widely existing in atmosphere. However, the monotonous and rigid structures of previously developed generators have heavily restricted their applications in complex and highly deformable working conditions. Herein, by a rational configuration design with a versatile laser processing strategy, graphenebased hygroelectric generators (GHEGs) of sophisticated architectures with diversified...

Biological Nanofibrous Generator for Electricity Harvest from Moist Air Flow

“…Owing to the presence of hydrophilic oxygen‐containing groups (e.g., carboxyl, hydroxyl, and epoxy groups), moisture could diffuse easily into GO membranes and dissociated H + ions from GO surfaces. With a gradient distribution of oxygen‐containing groups within a GO membrane, the concentration gradient of H + ions would be produced upon exposing to a humidity variation (e.g., human respiratory and finger touch) and hereby generated an electric pulse . The concentration gradient of H + ions was also observed in homogeneous GO membranes during the moisture diffusion process, in which the generated voltage, however, dropped down when the membranes were totally wetted by moisture.…”

Effect of Perforation on the Thermal and Electrical Breakdown of Self‐Rolled‐Up Nanomembrane Structures

“…[2,22,24,25] Tensile strain is generated primarily from [SiN] bonds interaction, which occurs more during high-frequency (HF) deposition condition; these bonds' dominance is caused by the smaller mean free path of the radicals generated by the plasma. [22,27,28] When the annealing temperature is sufficiently higher than the film deposition temperature, the hydrogen and ammonia byproducts diffuse out and leave more [SiN] bonds causing a decrease in compressive stress and an increase in tensile strain, respectively, in both of the layers. [22,27,28] When the annealing temperature is sufficiently higher than the film deposition temperature, the hydrogen and ammonia byproducts diffuse out and leave more [SiN] bonds causing a decrease in compressive stress and an increase in tensile strain, respectively, in both of the layers.…”

Two‐dimensional materials of group‐IVA boosting the development of energy storage and conversion

“…In summary, we have given a systematic and comprehensive review regarding general synthesis methods and advanced practical applications of 2D group-IVA materials according to the state-of-the-art research advances. As the emergence of graphene, its exotic properties and rich reserves of group-IVA elements shed light on the engineering of group-IVA 2D nanosheets with expected 26 and desirable power being realized in novel optoelectronic and thermoelectric devices.…”