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This current investigation explored the thermal conversion process of castor wood into biochar, which was subsequently harnessed for removing naproxen from pharmaceutical industrial effluent via adsorption. Surface composition analyses conducted through scanning electron microscopy–energy dispersive X‐ray, laser‐induced breakdown spectroscopy, and Fourier‐transform infrared studies unveiled the presence of nano MgO particles within the adsorbent material. Employing optimization techniques such as response surface methodology facilitated a refined approach to batch study. The optimized conditions for batch naproxen sodium (NPX) adsorption on nano‐MgO‐modified biochar were identified as pH 4, 1.5 g/L adsorbent dosage, and a 120‐min contact time maintaining a constant NPX concentration of 10 mg/L. The adsorption capacity was calculated to be 123.34 mg/g for a nano‐magnesium oxide‐modified castor wood biochar (modified biochar) and 99.874 mg/g for pristine castor wood biochar (pristine biochar). Fenton's reagents comprising 15 mM of FeSO4 (7H2O) and 25 mM of H2O2 have been scrutinized under conditions of pH 3.0, a reaction time of 30 min, a temperature of 30°C, and stirring at 120 rpm, followed by batch adsorption treatment. The COD, NH3–N, NO3−, PO43−, and NPX removal percentages was found to be 90%, 87%, 79%, 80%, and 90%, respectively. Thus nano MgO‐modified biochar holds promise of treatment of pharmaceutical effluent. [ABSTRACT FROM AUTHOR]

This work involved the preparation of pristine and iron nanoparticle-loaded biochar from a water chestnut shell to remove diclofenac sodium (DCF) containing effluent of pharmaceutical origin. To create suitable forecasting equations for the modelling of the DCF adsorption onto the adsorbent, response surface methodology (RSM) was used. The parameters, e.g. pH, adsorbent mass, DCF concentration and contact time, were used for the modeling of adsorption. The RSM model predicts that for 98.0% DCF removal, the ideal conditions are pH 6, an adsorbent dose of 0.5 g L−1, and a contact time of 60 min with an initial adsorbate concentration of 25 mg L−1 at 303 K. The maximum capacity deduced from the Langmuir model was 75.9 mg g−1 for pristine water chestnut shell biochar (pWCBC) and 122.3 mg g−1 for magnetically modified nano-Fe2O3 biochar (mWCBC). Under equilibrium conditions, the Langmuir model was the best-suited model compared to the Temkin and Freundlich models. The adsorption data in this investigation efficiently fitted the pseudo-second-order model, emphasizing that chemisorption or ion exchange processes may be involved in the process. The WCBC demonstrated recyclability after 10 cycles of repeated adsorption and desorption of DCF. A combined coagulation adsorption process removed COD, NH3–N, NO3−, PO43−, and DCF by 92.50%, 86.41%, 77.57%, 84.54%, and 97.25%, respectively. This study therefore shows that coagulation followed by adsorption onto biochar can be a cost-effective substitute for conventional pharmaceutical wastewater treatment. [ABSTRACT FROM AUTHOR]

TiO2 material has gained significant attention for large‐scale energy storage due to its abundant, low‐cost, and environmentally friendly properties, as well as the availability of various nanostructures. Phosphorus doping has been established as an effective technique for improving electronic conductivity and managing the slow ionic diffusion kinetics of TiO2. In this study, non‐doped and phosphorus doped TiO2 materials were synthesized using sodium alginate biopolymer as chelating agent. The prepared materials were evaluated as anode materials for lithium‐ion batteries (LIBs). The electrodes exhibit remarkable electrochemical performance, including a high reversible capacity of 235 mAh g−1 at 0.1 C and excellent first coulombic efficiency of 99 %. An integrated approach, combining operando XRD and ex‐situ XAS, comprehensively investigates the relationship between phosphorus doping, material structure, and electrochemical performance, reinforced by analytical tools and first principles calculations. Furthermore, a full cell was designed using 2 %P‐doped TiO2 anode and LiFePO4 cathode. The output voltage was about 1.6 V with high initial specific capacity of 148 mAh g−1, high rate‐capability of 120 mAh g−1 at 1 C, and high‐capacity retention of 96 % after 1000 cycles at 1 C. [ABSTRACT FROM AUTHOR]

Lithiated oxides like Li[NixCoyMnz]O2 (x + y + z = 1) with high nickel content (x ≥ 0.8) can possess high specific capacity ≥200 mA h g−1 and have attracted extensive attention as perspective cathode materials for advanced lithium-ion batteries. In this work, we synthesized LiNi0.9Co0.1O2 (NC90) materials and studied their structural characteristics, electrochemical performance, and thermal behavior in Li-cells. We developed modified cationic-doped NC90 samples with greatly improved properties due to doping with Mo6+ and B3+ and dual doping via simultaneous modification with these dopants. The main results of the current study are significantly higher capacity retention, greatly reduced voltage hysteresis, and considerably decreased charge-transfer resistance of the Mo and Mo–B doped electrodes compared to the undoped ones upon prolonged cycling. We also revealed remarkable microstructural stability of the Mo-doped electrodes, whereas the undoped samples were unstable and exhibited networks of cracks developed upon cycling. Using density functional theory, we modeled the electronic structure of the undoped, Mo, B single-doped, and Mo–B dual-doped samples and established that the Ni-site is preferred over Co and Li sites. Additionally, density functional theory-based bonding strength calculations suggest that the dopants form strong bonds with oxygen, possibly reducing oxygen release from the cathode. An important finding is that B-dopant tends to segregate to the surface of NC90 similarly to that in NCM85 materials, as shown in our previous reports. In conclusion, this study presents a general approach for effectively stabilizing high-energy Ni-rich layered cathodes charged up to 4.3 V. [ABSTRACT FROM AUTHOR]

Spin–orbit coupling (SOC) combined with broken inversion symmetry plays a key role in inducing Rashba effect. The combined spontaneous polarization and Rashba effect enables controlling a material's spin degrees of freedom electrically. In this work, we investigated an electronic band structure for several combinations of TiX2 monolayers (X = Te, S, and Se): TiTe2/TiSe2, TiTe2/TiS2, and TiSe2/TiS2. Based on the observed orbital hybridization between the different monolayers in these heterostructures (HSs), we conclude that the most significant Rashba splitting occurs in TiSe2/TiS2. Subsequently, we used fluorine (F) as an adatom over the surface of TiSe2/TiS2 at hollow and top sites of the surface to enhance the Rashba intensity, as the F adatom induces polarization due to the difference in charge distribution. Furthermore, by increasing the number of F atoms on the surface, we reinforced the band splitting, i.e., we observe Rashba splitting accompanied by Zeeman splitting at the valence-band edge states. Berry curvatures at K and K′ with equal and opposite nature confirm the existence of valley polarization. The computationally observed properties suggest that these HSs are promising candidates for spin–valley Hall effect devices and other spintronic applications. [ABSTRACT FROM AUTHOR]

Using first principles density functional theory, we have studied the interaction mechanism of NO2 and SO2 gas molecules on an MoB2 monolayer, for gas sensing applications. The selectivity for a particular gas by the sensor has been analyzed through electronic structure calculations and adsorption studies. The calculations have been performed by considering the fact that the MoB2 monolayer as a sensing material encounters a change in its electrical properties, when gas molecules with different orientations get adsorbed on the surface. From the density of states study, we find better selectivity for NO2 as compared to SO2, as the latter leaves the electronic structure of the sensing material unaffected. Further, the adsorption curves support the above fact as the larger value of adsorption energy (Ead∼−1 eV) for NO2 indicates stronger adsorption. The chemisorptive nature for NO2, in contrast with the relatively weaker physisorption for SO2, additionally supports the fact that NO2 gas has a better perspective for MoB2 sensor application. Charge density plots for each case are in good agreement with the above conclusions. The faster recovery time attributes the MoB2 monolayer better as a sensor material for NO2 interaction. [ABSTRACT FROM AUTHOR]

A new multisensor (i.e. resistive and magnetic) CrI3-WTe2 heterostructure (HS) to detect the toxic gases BrF3 and COCl2 (Phosgene) has been theoretically studied in our present investigation. The HS has demonstrated sensitivity towards both the gases by varying its electronic and magnetic properties when gas molecule interacts with the HS. Fast recovery time (<0.14 fs) under UV radiation has been observed. We have considered two configurations of BrF3 adsorbed HS; (1) when F ion interacts with HS (C1) and (2) when Br ion interacts with HS (C2). In C1 case the adsorption energy Ead is observed to be −0.66 eV while in C2 it is −0.95 eV. On the other hand in case of COCl2Ead is found to be −0.42 eV. Magnetic moments of atoms are also found to vary upon gas adsorption indicates the suitability of the HS as a magnetic gas sensor. Our observations suggest the suitability of CrI3-WTe2 HS to respond detection of the toxic gases like BrF3 and COCl2. [ABSTRACT FROM AUTHOR]