Prelithiation is effective for compensating active lithium-ion (Li+) loss in silicon (Si)-based battery electrode materials. However, owing to the dynamic growth of the solid electrolyte interface (SEI), capacity fading remains the biggest challenge for the industrialization of Si electrodes. To address this problem, a novel ether-based prelithiation reagent was rationally designed by exploiting the weak solvent-solute coordination and the competitive reduction mechanism among electrolyte components. Precise regulation of the Li+ solvation structure enhanced Li+ transport during prelithiation, achieving an exceptional initial Coulombic efficiency (ICE) of similar to 100% for the Si/carbon (Si/C) anode after performing contact prelithiation for 2 min. Furthermore, the lithium fluoride (LiF)-rich interface with high mechanical toughness was pre-formed to assist in the formation of a stable SEI film by controlling the lowest unoccupied molecular orbital (LUMO) energy and binding energy of the prelithiation reagent, thereby improving the half-cell cycle performance. Consequently, the ICE of the full-cell incorporating the prelithiated Si/C anode increased by 40% compared with that containing as-received materials, and the corresponding energy density was 551.2 Wh kg-1 based on the electrode material after 3 cycles. Furthermore, theoretical calculations combined with in situ characterization techniques confirmed the strong potential of the contact prelithiation design strategy for large-scale industrial applications. (sic)(sic)(sic)(sic)(sic)(sic)(sic) (Si) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (Li+) (sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (SEI) (sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Si(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)-(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)Li+(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic) (Si/C) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)100%(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (ICE) .(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (LUMO) (sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (LiF) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)SEI(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)Si/C(sic)(sic)(sic)(sic)(sic)(sic)(sic)ICE(sic)(sic)(sic)40%, (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)551.2 Wh kg-1 ((sic)(sic)(sic)(sic)(sic)) .(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Si/C(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

The pursuit of high-energy-density, safe, and sustainable power sources has made all-solid-state lithium-ion batteries (ASSLIBs) a cornerstone of modern energy storage technology. Exploring alternate anode materials is crucial for the efficient fabrication of these batteries. Tin (Sn)-based electrodes are a promising contender owing to their high theoretical capacity, good electrical conductivity, and suitable operating potential. At the same time, the alloying-dealloying process between Li and Sn results in volume change, which remains a major obstacle in commercialization of these materials. The present study investigates micron-sized Sn-based composites as anodes for all-solid-state lithium-ion batteries using hydride-based solid electrolytes. The work emphasized on achieving robust electrochemical performance through simple, low-cost and scalable electrode fabrication without employing any complex synthesis routes. A composite electrode was prepared through a simple ball milling approach, with acetylene black (AB), which helps in controlling volume expansion without contributing much in overall cost and hydride based solid electrolyte, which facilitates faster ionic transportation. In particular, LiBH4 and 3LiBH4–LiI, two hydride-based solid electrolytes, are employed to explore the performance of Sn in different environments. The results of cyclic voltammetry and the galvanostatic charge-discharge technique suggested the multi-staged lithiation of the Sn anode. From ex-situ XRD analysis, the alloying reaction mechanism between Li–Sn and the formation of the highly lithiated Li17Sn4 phase through the formation of various intermediate phases is successfully confirmed. The effect of current rates on different Sn-composite anodes has also been analysed by performing rate capability tests at varying rates from 0.1C to 1C. The overall findings contribute towards the low-cost and scalable development of high-capacity Sn-based composite anodes for ASSLIBs, as well as the potential impact of AB and hydride-based solid electrolytes.

The increasing demand for high-energy-density lithium-ion batteries necessitates the development of an alternative anode material that can surpass the limitations of the graphite anode. Among the potential candidates, germanium (Ge) is an interesting anode material for lithium-ion batteries owing to its high theoretical capacity and higher lithium-ion diffusivity. This study investigates the lithiation mechanism, electrochemical performance, and structural integrity of Ge-based composite as anode for an all-solid-state lithium-ion battery (ASSLIB). A composite electrode consisting of germanium (Ge), electronically conductive acetylene black (AB), and ionically conductive lithium borohydride (LiBH4) was synthesized by a simple high-energy ball-milling approach. The electrochemical performance evaluation in a half-cell configuration revealed that the Ge-LiBH4-AB electrode exhibits excellent electrochemical performance with a reversible lithiation capacity of 1424.7 mAh g−1 with an initial coulombic efficiency of 93.25

MgH2 has garnered attention for its robust capacity (7.6 wt%) and economic viability. However, its sluggish hydrogen desorption kinetics and elevated hydride decomposition temperature pose significant hurdles. This study delves into the catalytic prowess of the ternary metal oxide Na2CrO4, enriched with alkali and transition metals, in augmenting MgH2 behaviour. The findings elucidate that the introduction of 10 wt% Na2CrO4 slashes the decomposition temperature of MgH2 to 215.6 degrees C, a stark contrast to the 417 degrees C observed for pristine MgH2. Employing the Kissinger equation, a significant decrement of 58.5% in the activation energy for desorption was observed for the composite with 10 wt% Na2CrO4 catalyst. The activation energy Ea was calculated as 70.5 f 4.3 kJ/mol for desorption while for absorption it is 72.1 f 3.8 kJ/mol. Thermodynamic profiles were charted as pressure-composition isotherms stated about unchanged enthalpy & entropy. The rate measure analysis indicated a significant enhancement in hydrogen absorption rates for catalyzed composites by achieving 5.19 wt% hydrogen absorption in just 1 min at 300 degrees C and rate of absorption is observed as 0.05 wt% per minute at 50 degrees C. Kinetic fitting with JMAK model unfolded dimensional defect mechanism for hydrogen absorption. Morphological, structural, and phase transition dynamics during reactions were meticulously scrutinized by employing cutting-edge techniques such as SEM-EDX and X-ray diffraction (XRD). The catalytic mechanism of kinetic enhancement was explored via XPS analysis and it is suggested that in-situ formed Cr2O3 and other species from the precursor Na2CrO4 is responsible for fast de/hydrogenation.

Magnesium has long been hailed as a frontrunner for hydrogen storage, but its real-world potential has been limited by sluggish kinetics and stubborn thermodynamics. This study presents an exciting breakthrough by utilizing Li4Ti5O12 (LTO) as a catalyst with varying concentration from 5 to 15 wt% by doping into MgH2 using ball milling procedure. It had been found to dramatically enhance the hydrogen storage capabilities. MgH2-15 wt % Li4Ti5O12 composite demonstrated outstanding hydrogen absorption even at lower temperature as compared to that of the milled magnesium hydride. The activation energy for hydrogen uptake reduced from 169.9 f 3.3 kJ/mol in pure MgH2 to an impressively low 76.4 f 3.3 kJ/mol with the catalyst addition. This powerful catalytic effect not only accelerated hydrogen uptake but also lowered the desorption onset temperature to just 187.3 degrees C, achieving a high reversible capacity of 6.38 wt%. The MgH2-15 wt% Li4Ti5O12 composite absorb hydrogen nearly 2.30 wt% at 100 degrees C and 4.33 wt% H2 at 250 and 300 degrees C within 10 min. The observed kinetic model progression from R2 to D4 with increasing temperature from 50 degrees C to 300 degrees C offers important mechanistic insight. It demonstrated how catalyst can significantly enhance sorption kinetics by improving hydrogen mobility by altering the reaction interface. Thermodynamic measurements indicated approximately no-enthalpy change (Delta H = 72.1 kJ/mol), confirming catalytic role of LTO. XRD analysis showed reversible phase transformation between Mg and MgH2, with Li4Ti5O12 remaining stable throughout cycling. SEM and EDS mapping confirmed a uniform dispersion of Li4Ti5O12 on MgH2 surfaces, enhancing catalytic sites and accelerating hydrogen sorption kinetics. The results indicated Li4Ti5O12 as effective catalyst for MgH2 as hydrogen storage material, offering insights for developing advanced metal oxide catalysts and opening the door to highly efficient, durable, and practical Mg-based hydrogen storage materials for the future energy solutions.

The development of high-capacity and safe anode materials remains a major challenge for all-solid-state lithium-ion batteries. Metal hydrides have emerged as promising candidates due to their high theoretical capacity and low operating potential; however, their poor electronic conductivity often limits performance. In this study, we systematically investigated vanadium lithium hydride (V-LiH) composite anodes containing different amounts of acetylene black (AB) and LiBH₄ as the solid electrolyte. Galvanostatic electrochemical cycling and galvanostatic intermittent titration technique (GITT) were performed to evaluate the influence of conductive carbon content on the voltage profile, polarization, and reaction stability. Cells with less than 20 wt.

Nanomaterials, defined by at least one dimension below 100 nanometres, have emerged as a transformative class of materials due to their unique size-dependent properties. From medicine and energy to electronics and environmental remediation, nanomaterials are enabling breakthroughs across disciplines. This review highlights recent developments in nanomaterial synthesis, examines their distinctive properties, and explores diverse applications. Challenges related to toxicity, scalability, and regulatory frameworks are also discussed, with a forward-looking view on future directions.

In the face of depleting fossil fuel reserves and perilous environmental detriment caused by these fuels, mankind is to meet the increasing energy demands, and eliminating the fossil fuel dependency can be achieved by the development and utilization of next-generation batteries. Many different materials, including metals, oxides, and chalcogenides have been investigated as effective electrodes in recent decades. Li has the highest capacity of the metals, around 3860 mA.h.g−1. However, it suffers from dendritic development during cycling, which is the most significant impediment to practical use. Liquid metal batteries are an excellent approach to resolving this issue. These batteries are composed of liquid-liquid electrode and electrolyte interface which eliminate the dendrite formation and provide superior performance at the higher current densities. Several challenges related to this field must be addressed to improve future practical approaches. This chapter covers a detailed insight from the fundamentals to the most recent developments in this sector. The basic understanding of electrochemistry of liquid metal batteries as derived from diverse research initiatives has been thoroughly reviewed. This chapter not only includes the basics of liquid metal batteries but also delivers the research work done for the development of the next generation of liquid metal batteries.

The urgent global demand for safer, high-energy-density storage solutions has placed all-solid-state lithium-ion batteries at the forefront of next-generation energy technology. Herein, we report the first successful demonstration of a full cell using a hydride-based conversion anode (MgH2-KNbO3) paired with a LiNi0.33Mn0.33Co0.33O2 (NMC 111) cathode for all-solid-state Li-ion batteries, setting a benchmark for hydride-based energy storage. Half-cell evaluations revealed excellent electrochemical behavior across a wide temperature range (30-120 degrees C). Cyclic voltammetry showed stable redox peaks over the cycles, while galvanostatic charge-discharge profiles displayed distinct plateaus at 0.48 and 0.55 V, confirming strong reversibility and structural stability. Further, rate capability testing over 40 cycles at current rates of 100-500 mu A (current density of 82-411 mA g(-1)) demonstrated stable cycling with sustained capacity retention. To assess real-world potential, the system was advanced to a full-cell configuration (MgH2@KN+LiBH4-LiI+AB||LiBH4-LiI||NMC+LiBH4-LiI+AB). The cell delivered an impressive initial charge/discharge capacity of 1174/915 mAh g(-1) at 60 degrees C, outperforming many commercial anodes, and maintained stable operation for up to 100 cycles across high-temperature to room-temperature conditions. At 90 degrees C, the full cell preserved 22% (charge) and 20% (discharge) capacities after 100 cycles, while at 30 degrees C, it still achieved strong initial charge/discharge capacities of 111/109 mAh g(-1), proving its capability to function under ambient conditions. A key factor in performance was the catalytic effect of KNbO3 and the utilization of a solid solution of LiBH4-LiI, which enhanced the interfacial conductivity and charge transfer efficiency.

Ammonia (NH_3) absorption drives LiBH_4·xNH_3 through a re-entrant "solid-liquid-solid" transition: LiBH_4· NH_3 is a well-defined solid ammoniate, compositions near LiBH_4· 2NH_3 are liquid-like or partially liquefied, whereas LiBH_4· 3NH_3 returns to a more rigid, non-liquid ammoniate state. However, the microscopic origin of this unintuitive response remains a long-lasting mystery. Here, we uncover its mechanism. Cross-database analysis identifies borohydrides as a particularly state-diverse and composition-responsive material family. Structure prediction and ab initio molecular simulations reveal that NH_3 progressively replaces BH_4^- in the Li coordination shell. The liquid-like state emerges not at the highest NH_3 loading but near x ≈ 2, where Li-N and Li-B coordination modes are strongly mixed, coordination memory is weakest, and the sampled Li-N/N⋯B coordination landscape is broadest. Further ammoniation produces Li-N-dominant coordination and slows BH_4^-/NH_3 contact renewal, resulting in increased network persistence and recovery of a rigid ammoniate state. Pressure-composition isotherm, ^1H and ^11B nuclear magnetic resonance, and Raman measurements support this non-monotonic state evolution and the associated BH_4^-/NH_3 reorganization. These findings transform ammonia-induced liquefaction from an empirical phase anomaly into a competition among native-network disruption, mixed-coordination frustration, and ligand-built network reconstruction, providing a framework for chemically switching between transport-favouring fluidity and stability-favouring rigidity in hydrogen-rich materials.

Metal hydride (MH)-coupled methanol steam reforming (MSR), in which MSR is coupled with the hydrolysis of MH, is an attractive strategy for onsite hydrogen generation as it offers a high hydrogen density, high hydrogen purity and balanced thermal effect. This study provides a comprehensive mechanism study on the MH-coupled MSR over Cu/CaH2 using online mass spectroscopy coupled with isotope labelling and in situ Fourier-transformed infrared spectroscopy. Results show that the hydrolysis of MH and MSR over Cu proceeds simultaneously via a formate-mediated pathway. The stepwise dehydrogenation of methanol primarily occurs on the Cu surface, while CaH2 effectively activates CH3OH at low temperatures by supplying the hydrolysis heat to the endothermic MSR. Although Ca(OCH3)2 and Ca(HCOO)2 can be formed when CaH2 is introduced, they are not active intermediates in the MH-coupled MSR due to their high thermal stability. Instead, they are converted back to CH3OH and HCOOH via hydrolysis.

This study presents a systematic investigation of highly efficient bulk Si-based composite anodes for the development of an all-solid-state lithium-ion battery. Herein, composite electrode materials prepared through a simple, low-cost, and scalable high-energy ball milling approach has been reported, which was intended to avoid complex and costly nano-structuring routes. The as-prepared electrodes demonstrated stable and robust electrochemical performance when evaluated in a half-cell configuration with hydride solid electrolytes. To elucidate their electrochemical behaviour, interfacial characteristics, and to assess performance differentials across key parameters, each cell was systematically characterized using Galvanostatic Charge-Discharge, Cyclic Voltammetry, and Electrochemical Impedance Spectroscopy techniques. The Si-AB electrode delivered a high initial discharge capacity of 3448 mAh g-1, and a high initial coulombic efficiency (ICE) of 98%, On the other hand, Si-LiBH4-AB revealed a discharge capacity of 2998 mAh g-1 with an ICE of 96.2%. The compatibility of 3LiBH4-LiI solid electrolyte was also studied using Si-(3LiBH4-LiI)-AB as a composite electrode. During the study of the lithiation mechanism, the formation of the Li13Si4 and Li17Si4 phases at high temperature were experimentally confirmed through an ex-situ X-ray diffraction study. Furthermore, the study highlights a multifaceted perspective on the integration of acetylene black with silicon and the potential implications with hydride-based electrolytes LiBH4 and 3LiBH4-LiI.

This study systematically investigates the effect of different surface modification agents (acetone, graphite, BN, and TiO2) on the hydrogen absorption performance and oxidation resistance of TiFe0.7Mn0.3 hydrogen storage alloys. Based on the powder X-ray diffraction (XRD) measurements, hydrogen absorption kinetics analysis, and X-ray photoelectron spectroscopy (XPS) analyses, it is demonstrated that the chemical nature and stability of the surface-modified layers predominantly govern hydrogen absorption behavior. Acetone-added and milled TiFe0.7Mn0.3 alloys were shown to generate transient Ti-O-C oxycarbide phases, enabling rapid activation but resulting in only short-lived improvement due to fast oxidation. Graphite modification promotes the formation of TiC, consuming active Ti sites and significantly suppressing both initial kinetics and long-term durability. BN introduces a partially protective nitride/oxide layer that retards oxidation, allowing the alloy to retain measurable hydrogen absorption despite gradual kinetic degradation during aging. In contrast, TiO2 modification offers the most effective preservation of durability while maintaining the initial hydrogen absorption kinetics. Ball milling with TiO2 induces partial reduction of Ti species and strong interfacial electronic interactions in TiFe0.7Mn0.3, forming a modified layer with a Ti-Fe-Mn-O species that suppresses surface oxidation, stabilizes active Ti sites, and enhances hydrogen absorption kinetics and durability. Although prolonged aging gradually restores Ti4+and Fe2+dominated surface states, the persistence of metallic species at early aging stages demonstrates that TiO2 modification effectively delays alloy deactivation and preserves partial hydrogen absorption activity.

Malachite Green (MG) is a cationic triphenylmethane dye which is widely used in the textile and aquaculture industries. It is recognized as a persistent and hazardous organic pollutant due to its carcinogenic, genotoxic, and ecotoxic characteristics. Present investigation targets the development of sustainable adsorbent from the waste peanut (Arachis hypogaea) shells by using microwave-assisted pyrolysis method and alkali-induced activation to enhance surface properties. This synthesized alkali-activated peanut shell biochar was systematically characterized using XRD, SEM EDX, FTIR, and batch adsorption experiments were performed to investigate the removal of MG from aqueous solution, examining the influence of pH, contact time, temperature, and adsorbent dosage. Adsorption capacity for peanut shell biochar is 28.34 mg of dye per gram of biochar and for alkali activated peanut shell biochar is 63.24 mg of dye per gram of biochar. Adsorption mechanism involves best fit for Freundlich isotherm indicating heterogeneous surface with varying adsorption sites, with second order kinetics. It is a spontaneous endothermic process involving weak Vander Waal's and pi-pi interactions as prevalent processes of adsorption. The findings confirm that alkali activation significantly improves porosity, surface functionality, and adsorption capacity. PSB and NaOH PSB treatment significantly reduced turbidity (51%), TSS (36%), Oil and Grease (59%), BOD and COD. Nearly 35% reduction in the Water Quality Index (WQI) was observed after the biochar treatment rendering water quality suitable for washing and other purposes.

In this study, MgO was incorporated into the extensively studied solid electrolyte material, lithium borohydride (LiBH4), to enhance its poor ionic conductivity at ambient temperature. The addition of MgO was proved to significantly improve its ionic conductivity by approximately four orders of magnitude at 30 degrees C compared to the low-temperature phase (less than 115 degrees C) of pristine LiBH4. Based on this electrolyte, all-solid-state batteries employing LiCoO2 as the cathode and MgO-modified LiBH4 as the electrolyte were successfully fabricated and operated in the low-temperature range. Moreover, the initial charging process exhibited anomalous electrochemical behavior, delivering a remarkably high specific capacity of 285.2 mAh/g with an unconventional charge plateau at 1.6 V, which deviates substantially from the typical electrochemical characteristics of LiCoO2. To understand the charging mechanism from thermochemical and electrochemical views, a series of mechanistic characterizations was performed on the battery. Thermogravimetric analysis revealed a small amount of hydrogen evolution (<= 0.2 wt%) at phase transition temperatures, while solid-state NMR spectroscopy confirmed the formation of B-O bonds, providing evidence for redox reactions involving LiBH4. However, comparative electrochemical experiments and X-ray diffraction (XRD) analysis excluded the influence of the thermal decomposition of LiBH4 during the charging process. The charging mechanism that controlled the electrochemical behavior of this system was clarified in a detailed discussion.

Borohydrides are promising ammonia (NH3) storage materials for controlling the storage pressure of NH3, where the reaction mechanism between borohydrides and NH3 is key to designing suitable properties to meet demands. However, the origin of the characteristics of NH3 absorption processes, such as the formation of solid complexes and solution phases, is unclear. In this work, the NH3 absorption properties of the LiBH4 and NaBH4 mixed system are investigated by thermodynamic and spectroscopic analyses, and the results are compared with those of single components. Although the NH3 absorption properties of a mixture in the low NH3 absorption region was dominated by an independent reaction of LiBH4, a decrease in plateau pressure by synergistic effects was revealed from 1.5 mol mol-1. In this reaction process, NH3-induced liquefaction of the mixture occurred due to the dissolution of LiBH4(NH3)3 into a NaBH4 based solvation phase, NaBH4(NH3)2. The synergistic thermodynamic variation originated in the liquefaction of NaBH4. In fact, the required NH3 absorption amount at 243 K was higher than that at 293 K because the transformation conditions to the liquid phase of NaBH4 at low temperature were changed by stabilization of the solid NH3 coordinated phases. In addition, theoretical simulation based on molecular models suggested a limit to the NH3 absorption number for forming a stable NH3-coordinated phase. The above-obtained results are recognized as important knowledge for establishing guidelines for material design of NH3 absorption materials.

Recently, the kinetic improvement of the nitrogenation reaction of lithium hydride (LiH) to form lithium imide (Li2NH) by adding a scaffold was reported. The scaffold prevents agglomeration of Li2NH and maintains the activity of LiH, achieving a reduction in reaction temperature and an increase in reaction rate. In this work, a Li–Si alloy, Li22Si5, was used as a starting material to form nano-sized LiH dispersed in a Li alloy matrix. Lithium nitride (Li3N) is generated by the reaction between Li22Si5 and N2 to form Li7Si3, and then Li3N is converted to LiH with ammonia (NH3) generation during heat treatment under H2 flow conditions. Since Li3N is formed at the nano-scale on the surface of alloy particles, LiH generated from the above nano-Li3N is also nano-scale. The differential scanning calorimetry results indicate that direct nitrogenation of LiH in the alloy matrix occurred from around 280 °C, which is much lower than that of the LiH powder itself. Such a highly active state might be achieved due to the nano-crystalline LiH confined by the Li alloy as a self-transformed scaffold. From the above experimental results, the nano-confined LiH in the alloy matrix was recognized as a potential NH3 synthesis technique based on the LiH-Li2NH type chemical looping process.

As a promising hydrogen storage material with high gravimetric density and low cost, MgH2 is an attractive candidate for practical application but still facing limitations due to its poor kinetics. In this work, the nano-structured CuxO mateirals in PANI matrix were developed as catalysts to enhance the hydrogen desorption behaviors of MgH2 in the form of PANI, CuxO/PANI-1, CuxO/PANI-2, and CuxO/PANI-3. The CuxO/PANI catalyst is effective in decreasing the desorption peak temperature of MgH2 and among all the forms of this catalyst, the catalytic efficiency of CuxO/PANI-3 was found significantly higher as compared to the others. Thermal analysis measurements show that the desorption peak temperature of CuxO/PANI-3 doped MgH2 is reduced to 304 degrees C in comparison to 347 degrees C of the undoped MgH2. At the same time, the activation energy of hydrogen desorption is also reduced to 135.6 kJ/mol, whereas it was observed as 171 kJ/mol for pristine MgH2. Structural identification from X-ray diffraction profile reveals that CuO phase is significantly present that might have contributed to the kinetic tuning of MgH2 by the addition of CuxO/PANI-3 as catalyst. Furthermore, the effect of extending milling period on the catalytic behavior has been investigated in case of MgH2+10 wt% CuxO/PANI-3 composite. The lesser reduction in the dehydrogenation peak temperature and no change in the onset desorption temperature indicate that kinetic tuning of MgH2 cannot be improved by prolonged milling.

The widespread presence of antibiotics like ciprofloxacin in hospital wastewater poses serious environmental and health risks due to antibiotic resistance. This study presents the synthesis and application of a magnetically separable biochar–magnetite nano-composites for efficient adsorptive removal of ciprofloxacin. Biochar based adsorbents are sustainable, environmentally friendly, low cost and scalable with tuneable surface chemistry and regeneration capacity. In this study, orange peel biochar (CB) was doped with magnetite (Fe3O4) to prepare three different magnetic biochar-magnetite nano-composites CBC-2, CBC-5, CBC-10 which were examined for maximum removal efficiency of ciprofloxacin which is a popular broad-spectrum synthetic fluoroquinolone antibiotic. It is poorly metabolized, frequently excreted from body in unmetabolized and hence reported as a major pollutant in hospital waste water. The best adsorption efficiency was found at pH 8.0 and 298 K temperature by CBC-10 composite with the highest adsorption capacity ( 90