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Many materials with varied characteristics have been used for water purification and separation applications. Recently discovered graphene oxide (GO), a two-dimensional derivative of graphene has been considered as a promising membrane material for water purification due to its excellent hydrophilicity, high water permeability, and excellent ionic/molecular separation properties. This review is focussed on the possible versatile applicability of GO membranes. It is also known that selective reduction of GO results in membranes with a pore size of $0.35 nm, ideally suited for desalination applications. This article presents the applicability of graphene-based membranes for multiple separation applications. This is indeed the first review article outlining a comparison of GO and r-GO membranes and discussing the suitability for applications based on the porosity of the membranes.

Permeance indicates how fast the gas molecule transports through the membrane, usually expressed in gas permeation unit (GPU, 1 GPU = 10 −6 cm 3 (STP) cm −2 scmHg −1 ), while selectivity represents how efficiently the gas is separated from the mixture during the transportation. The nature of molecular transportation in membranes depends on the porosity and type of membrane materials, which can be understood by using mechanisms based on solution-diffusion, size-dependent molecular sieving, Knudsen diffusion, and Poiseuille flow. [3] Materials such as zeolites, [4][5][6] metalorganic frameworks (MOFs), [7][8][9] and carbon-based constituents [10][11][12][13][14] in the form of membranes have been intensively studied as gas barriers in the past. These materials are featured by tuneable nanosized pores, which provide sites for gas

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with diverse functional properties makes a fabric suitable for smart textiles, which can be well suited for numerous potential applications including protective clothing, health monitoring, wearable motion sensing, sports clothing, personal entertainment, and the Internet of Things. [1,2] Due to these revolutionary prospective applications, in recent times the interest in multifunctional wearable smart textiles has been increasing remarkably. [3] However, the existing smart textile manufacturing technology involves the processing of separately manufactured conductive threads with some complicated and timeconsuming steps like sewing, knitting, weaving, and embroidery. [4] Besides, fabrication of high electroconductive multifunctional fabric with good washing durability by maintaining a facile fabrication method is very challenging. Having extraordinarily high electrical, thermal, mechanical, hydrophobic, and many other significant properties, graphene and its derivatives (graphene oxide, GO and reduced graphene oxide, RGO) [5] have already demonstrated immense capability to be adsorbed (by covalent and hydrogen bond) onto fabrics and fabricated into smart textiles. [2,3,6] Presence of oxygenbearing (negative) functional groups (hydroxyl, carboxyl, and Graphene derivatives have the capability of forming chemical bonding with fabrics and show the potential to be used in smart textiles. However, the challenge is to fabricate highly conductive multifunctional fabric with good washing durability. Herein, reduced graphene oxide (RGO) and silver (Ag)/copper (Cu) nanoparticles (NPs)-coated durable electroconductive silk fabric is fabricated by facile dip and dry method using 3-glycidyloxypropyl trimethoxy silane as coupling agent (CA). Results show that RGO and NPs-coated fabrics not only demonstrate low surface resistance but also excellent electrothermal property, UV shielding, enhanced thermal stability, and outstanding hydrophobicity consistently in the following order: pure silk < silk-RGO < silk-CARGO < silk-CARGO -Ag < silk-CARGO -Cu. The addition of CA and NPs is found to have a significant impact on performance and washing durability. Cu incorporated samples (silk-CARGO -Cu) show a very low value of surface resistance (3.15 kΩ sq −1) and even after washing 20 times, the resistance (6.76 kΩ sq −1) is observed to be lower than unwashed non-Cu incorporated samples. Moreover, silk-CARGO -Cu also has the highest UV resistance, Joule heating, hydrophobicity, and thermal stability among all samples, which makes it well suited for numerous potential applications including protective clothing, health monitoring, motion sensing, and sports clothing.

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Graphene oxide has aroused significant interest for a range of applications owing to their outstanding physico-chemical properties. Specifically, the presence of a large number of reactive chemical moieties such as...

The water transport along graphene-based nanochannels has gained significant interest. However, experimental access to the influence of defects and impurities on transport poses a critical knowledge gap. Here, we investigate the water transport of cation intercalated graphene oxide membranes. The cations act as water-attracting impurities on the channel walls. Via water transport experiments, we show that the slip length of the nanochannels decay exponentially with the hydrated diameter of the intercalated cations, confirming that water transport is governed by the interaction between water molecules and the impurities on the channel wall. The exponential decay of slip length approximates non-slip conditions. This offers experimental support for the use of the Hagen-Poiseuille equation in graphene-based nanochannels, which was previously only confirmed by simulations. Our study gives valuable feedback to theoretical predictions of the water transport along graphene-based channels with water-attracting impurities.