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A required progress in developing effective membranes for diffusion dialysis provides a platform to explore novel hybrid membranes for acid recovery. This novel study investigated a feasibility of egg shell membrane powder in enhancing proton permeability of polysulfone membrane, thereby promoting a sustainable development in acid recovery. Hybrid membranes with different concentration loading of egg shell membrane to polysulfone were fabricated, characterized and analyzed in terms of water uptake, ion exchange capacity, chemical stability, thermal stability and mechanical stability and the viability towards effective acid recovery. Results revealed that, prepared EP membranes showed almost 5.55 folds greater proton permeability and very high separation factor than most commercially available DF- 120 membrane. Enhancement in performance and acid recovery in the whole work is credited to presence of amino acids groups in egg shell membrane with enormous amount of hydrogen bond donar and acceptor sites which helps in hydrogen bond formation, and occurrence of π- π interactions with polysulfone forming channels to effectively permeate hydrogen ions. Also, these structural interactions remarkably increased the membrane stiffness compared to pristine PSf membrane and showed better mechanical stability. The strategy behind this work is promising for developing high performance, sustainable product for rapid acid recovery which could be examined in detail to apply for industrial spent acid recovery.

The density functional theory framework is used to study geometry and electronic properties of pristine tricycle arsenene nanoribbon (T-AsNR) and Ga substituted T-AsNR. The stable geometry of both T-AsNR is ensured based on the formation energies. The obtained formation energies for T-AsNR and Ga-substituted T-AsNR are −4.462 and −4.512 eV/atom, respectively. Also, the band gap is calculated to be 0.635 and 0.212 eV, respectively for pristine and Ga substituted T-AsNR, which are semiconductors. Furthermore, T-AsNR is used as a base substrate to adsorb sulfisoxazole in the aqueous medium. Moreover, the adsorption of sulfisoxazole on both T-AsNR possesses chemisorption. Besides, the adsorption energy at the valley site of T-AsNR and Ga-substituted T-AsNR are −6.313 eV and −6.346 eV. The average energy gap variation for Ga-substituted T-AsNR was highest at the top site and is about 174.06%, whereas the pristine one showed 6.93 %. The change in the electronic properties of T-AsNR is observed with regard to band structure, electron density, and density of states spectrum. Thus, the outcome suggests that T-AsNR is a prominent adsorbing medium of sulfisoxazole in contaminated water.

The adsorption properties of benzene and phenol molecules on 4–8 arsenene nanotubes (4–8 AsNT) are investigated based on the DFT framework. The structural stability is confirmed with a formation energy of 4–8 AsNT, which has −3.696 eV/atom. The band structure and density of states spectrum reveal that 4–8 AsNT exhibits a band gap of 0.504 eV. The adsorption energy for the complex structure is noticed to be in the scope of −0.253 eV to −0.602 eV, which confirms that the benzene and phenol molecules are physisorbed on 4–8 AsNT. The charge transfer and electron density difference support the change in the electronic attributes of 4–8 AsNT due to the adsorption of benzene and phenol molecules on 4–8 AsNT. The chemi-resistive nature is observed upon adsorption of benzene/phenol on 4–8 AsNT. Thus, the study reveals that 4–8 AsNT can be employed as a chemical nanosensor for benzene and phenol detection.

Square-octagon phosphorene nanotubes (so-PNT) have aroused attention among researchers owing to their interaction with pesticide molecules. In the current report, the adsorption features of dichlobenil, and isoproturon on so-PNT at three different orientations (inner, octa, and tetra vacancy of so-PNT) are explored with the framework of density functional theory. Moreover, the adsorption features are conversed in terms of adsorption energy, band gap variation, charge transfer, and band structure maps. Besides, the adsorption aspects of dichlobenil and isoproturon are also demonstrated with regard to the density of states spectrum. The electron density difference of so-PNT articulates the adsorption features of target molecules. In addition, the outcome of the proposed study enunciates the chemisorption nature of dichlobenil, and isoproturon molecules on so-PNT. Thus, so-PNT can be considered as an efficient material for the removal of dichlobenil, and isoproturon molecules. Furthermore, the chemisorption process is attributed to the presence of polar groups and the aromatic rings in the targets system offering π- π interactions and stacking along with electron-donor–acceptor interactions between target contaminants and so-PNT.

The study reports the use of a novel membrane for heavy metal removal and salt rejection. Poly isobutylene alt maleic anhydride (PIAM) modified by sulfanilic acid is blended with polysulfone (PSf) in different concentrations. This induces surface charge and hydrophillicity in the otherwise hydrophobic PSf membranes. The so modified polymers and their blends are characterized by spectroscopic and microscopic techniques. Blend membranes show drastically enhanced performance with respect to water flux, water uptake and ion exchange capacity. SEM micrographs indicate the hydrophilic domains, –SO 3 H groups in the polymer to have formed cavities during phase inversion process, thus enhancing permeability. 100% rejection of PEG 2000 and 59% of NaCl rejection substantiated the nature of the membrane to be nanofiltration (NF) type. The prepared membranes were further evaluated for Cr (VI) removal, with removal efficiency reaching above 92%. The electronic coupling that occurs between SO 3 H − and Na + and the electrostatic interaction between metal ions and the charge on membrane facilitates NaCl and Cr (VI) rejection respectively. The study gains significance in use of such modified PIAM as blend material with any other polymer to enhance the native properties of the blend membrane.

We investigated the electronic features and structural firmness of θ–phosphorene nanosheet (TPNS) based on density functional theory. The formation energy endorses the structural firmness of TPNS. The semiconducting nature of TPNS with an energy band gap of 1.326 eV supports its use as a base substrate to adsorb toxic blood agents, such as HCN and ClCN. The adsorption characteristics of HCN and ClCN were established using adsorption energy, charge transfer, and deviation in band gap of TPNS. Also, the change in the electronic properties of TPNS upon adsorption of HCN and ClCN has conversed with regard to band structure, density of states spectrum, and electron density. The overall findings suggest the use of θ–phosphorene nanosheets as a sensing medium for toxic HCN and ClCN molecules.

In the present research, β-bismuthene nanosheet (β-BiNS) is used as a base substrate to adsorb two volatile organic vapors evolved from sewer headspace, namely, benzyl alcohol (BA), and 2-methyldecalin (MD). Initially, the structural firmness of β-BiNS is established using cohesive formation energy and observed to be stable. The surface adsorption of BA and MD molecules on β-BiNS are explored with regard to the density of states, energy gap variation, adsorption energy, and charge transfer. Besides, β-BiNS exhibits chemi-resistive behavior upon adsorption and desorption of BA and MD vapors, which indicates its use as chemosensor towards toxic vapors evolved from sewer headspace.

A photoactive float was fabricated with the modified titania to cause a feasible disinfection of water, contaminated with E. coli. The commercially available titania was doped with neodymium by pulverization technique to enhance its activity in sunlight and a multiapproach technique was used to evaluate the extended efficiency of the doped sample. X-ray diffraction patterns depicted the retention of anatase phase on doping and the existence of neodymium was confirmed by the energy dispersive atomic X-ray analysis and the X-ray photoelectron spectroscopy. Transmission electron microscopy and Bruner-Emmett-Teller analysis depicted a marginal increase in the particle size and a decrease in the surface area, respectively. Doping induces semiconductor behavior with lower band energy that could respond to visible light and exhibit better disinfection activity. The "f" and "d" transitions of the lanthanide in doped sample caused new electronic behavior of trapping/detrapping effect together with bandgap narrowing. The amount of malondialdehyde, protein, DNA and RNA released on destruction of E. coli was observed to be 0.915 × 10(-3) μg mL(-1), 859.912 μg mL(-1), 20.173 μg mL(-1) and 1146.073 μg mL(-1), respectively. The above analytical methods along with standard plate count method substantiated the enhanced disinfection efficiency of the doped sample in sunlight.