Reconstruction of Soil Components into Multifunctional Freestanding Membranes

Abstract

Multifunctional freestanding membranes are prepared by tuning the structure of ubiquitous soil components, viz. clay and humic acids. Cross-linking of exfoliated clay layers with purified humic acids not only conferred mechanical strength but also enhanced chemical robustness of the membranes. The percolated network of molecularly sized channels of the soil membranes exhibits characteristic nanofluidic phenomena. Electrical conductivity is induced to otherwise insulating soil membranes by heating in an inert atmosphere, without affecting their nanofluidic ionic conductivity. The soil membranes also provided a new platform to prepare and study mixed conducting materials. Strips of heated membranes are shown to exhibit excellent sensitivity toward NH 3 gas under atmospheric conditions.

Clay-Based Nanofluidic Membrane Derived from Vermiculite Nanoflakes for Pressure-Responsive Power Generation

“…The selectivity of the VM toward cations was evaluated by measuring the transmembrane potentials under concentration gradient, and the details are discussed in Figure S2. Under a 1000-fold concentration gradient of a KCl solution, the VM displayed a transmembrane potential of 0.2 V. The transport number of cations in the vermiculite nanofluidic channels was calculated to be 0.94 using eq 1 22…”

“…The selectivity of the VM toward cations was evaluated by measuring the transmembrane potentials under concentration gradient, and the details are discussed in Figure S2. Under a 1000-fold concentration gradient of a KCl solution, the VM displayed a transmembrane potential of 0.2 V. The transport number of cations in the vermiculite nanofluidic channels was calculated to be 0.94 using eq where E diff is the stable transmembrane potential, R is the universal gas constant, T is the room temperature, z is the number of moles of electrons, F is the Faraday constant, and C H and C L are the concentrations of the salt solution at high and low concentration chambers, respectively.…”

“…Layers of vermiculite can be readily exfoliated and reassembled to prepare flexible freestanding membranes, as illustrated in Scheme . The reconstructed vermiculite membrane (VM) displays many fascinating properties such as extraordinary proton conductivity, , self-repairing ability, switchable wettability, environmental responsiveness, nanoconfined catalytic activity, and extraordinary thermal and chemical stability. , The electrically insulating VM also possesses very high intrinsic conductivity and eliminates the need for external electrolytes . A nanofluidic membrane with such remarkable properties could play a crucial role in the fabrication of energy-harvesting and storage devices aimed at high-temperature applications.…”

Effect of Irrigation and Nitrogen Levels on Nitrogen Content, Uptake and Water Productivity of Clusterbean (Cyamopsis tetragonoloba) in IGNP Stage-II

“…Since nutrient uptake is a function of nutrient content of plant parts and total dry matter of the crop in terms of pod and haulm yields, application of nitrogen up to 40 kg ha -1 increased the uptake of N significantly. Significant improvement in nutrient contents and/or their uptake due to nitrogen application (upto 50 kg N ha -1 ) were observed by Patel et al, (1995), Chawale et al, (1995) and Deka et al, (2001). Protein content is directly related to nitrogen content and increases with increase in N content in seed.…”

Fabrication of Pressure-Responsive Energy Device from Nanofluidic Vanadium Pentoxide and Polymeric Hydrogel

“…To attain the required levels of ionic conductivity, various corrosive/inflammable liquid (or solid)-based electrolytes are used as electrolytes; however, these reactive electrolytes drastically reduce the lifetime of the devices. − Moreover, in most of the supercapacitors or batteries, the spacer/electrolyte is the most vulnerable component of the devices, the lifetime of which dictates the overall durability of the devices. In recent years, efforts were made to overcome these trade-offs by employing advanced nano- or biomaterial-based membranes that exhibit high nanofluidic ionic conductivity, thermal robustness, and chemical stability. − The percolated network of the molecularly sized nanochannels formed by the interlayer spaces of the reconstructed V 2 O 5 membrane is known to exhibit high stability and proton conductivity, and hence provide an ideal platform to fabricate chemically robust, thermally stable, and environmentally friendly power delivering systems.…”