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Nanomaterials and hydrogen production: A comprehensive Review of clean energy strategies, costs, and environmental implications
(Elsevier BV, 2025-09)
Fazil Qureshi
;
Mohammad Asif
;
Mohd Yusuf Khan
;
Abuzar Khan
;
Mohd Naved Khan
An increasing demand for energy coupled with rising pollution levels is driving the search for environmentally clean alternative energy resources to replace fossil fuels. Hydrogen has emerged as a promising clean energy carrier and raw material for various applications. However, its environmental benefits depend on sustainable production methods. The rapid development of nanomaterials (NMs) has opened new avenues for the conversion and utilization of renewable energy (RE). NMs are becoming increasingly important in addressing challenges related to hydrogen (H₂) generation. This review provides an overview of current advancements in H₂ production from biomass via thermochemical (TC) and biological (BL) processes, including associated costs, and explores the applications of nanomaterials in these methods. Research indicates that biological hydrogen (BL-H₂) production remains costly. The challenges associated with the TC conversion process are examined, along with potential strategies for improvement. Finally, the technical and economic obstacles that must be overcome before hydrogen can be widely adopted as a fuel are discussed.
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A comprehensive review on arsenic contamination in groundwater: Sources, detection, mitigation strategies and cost analysis
(Elsevier BV, 2025-01-15)
Mohd Wajahat Sultan
;
Fazil Qureshi
;
Salman Ahmed
;
HESAM, KAMYAB
;
Saravanan Rajendran
While groundwater is commonly perceived as safe, the excessive presence of trace metals, particularly arsenic (As), can pose significant health hazards. This review examines the current scenario of pollutants and their mitigations focusing on As contamination in groundwater across multiple nations, with a specific emphasis on the Indian Peninsula. Arsenic pollution surpasses the WHO limit of 10 ppb in 107 countries, impacting around 230 million people worldwide, with a substantial portion in Asia, including 20 states and four union territories in India. Analysis of the correlation between the aquifer and arsenic poisoning highlights severe contamination in groundwater originating from loose sedimentary aquifer strata, particularly in recently formed mountain ranges with geological sources presumed to contribute over 90% of arsenic pollution, i.e. a big environmental challenge. A myriad of techniques, including chromatographic, electrochemical, biological, spectroscopic, and colorimetric methods among others, are available for the detection and removal of arsenic from groundwater. Removal strategies encompass a wide array of approaches such as bioremediation, adsorption, coagulation/flocculation, ion exchange, biological processes, membrane treatment, and oxidation techniques specifically tailored for affected areas. Constructed wetlands help to eliminate heavy metal impurities such as As, Zn, Cd, Cu, Ni, Fe, and Cr. Their efficiency is influenced by design and environmental factors. Nanotechnology and nanoparticles have recently been studied to remove arsenic and toxic metal ions from water. Cost-effective solutions including community-based mitigation initiatives, alongside policy and regulatory frameworks addressing arsenic contamination, are essential considerations.
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Advancements in sorption-based materials for hydrogen storage and utilization: A comprehensive review
(Elsevier BV, 2024-11)
Fazil Qureshi
;
Mohammad Yusuf
;
Salman Ahmed
;
Moinul Haq
;
Alhafez M. Alraih
With its remarkable energy density and eco-friendly combustion properties, hydrogen stands as a beacon of hope in our quest to meet future energy needs while ushering in a cleaner, carbon-free era, making a significant impact on the path to a sustainable world. Nevertheless, the broader utilization of H2 faces hurdles concerning its generation, storage, and efficient utilization. Solid materials offer a promising avenue to address these challenges, as their properties can be readily tailored to enhance the efficiency of H2 generation, storage, and utilization. By manipulating their physical, chemical, thermal, and electronic attributes, solid materials can make substantial contributions across all three crucial aspects. Materials based on metal and complex hydrides show promise as hydrogen storage materials. The activation energy for hydrogen desorption is significantly reduced by transition metals doping, improving the materials' capacity to store hydrogen. Bimetallic nanoparticles of transition metals had outstanding catalytic and synergistic effects on the hydrogen adsorption/desorption properties of MgH2 when compared to the case of a single transition metals. Zeolites are superior to metal-organic frameworks due to their simplicity in synthesis, low thermal stabilities, and inexpensive cost. In general, hydrogen hydrates show promise as materials for hydrogen storage, but additional study is required to increase their hydrogen storage volumes, charging speeds, and cycle capabilities. Glass structure factors, such as the connectedness of the regional network, have a role in establishing the hydrogen permeabilities of glasses. The main limitations of these systems are their low volumetric hydrogen storage densities (<20 kg/m3) and the requirement for heating to liberate hydrogen. It's remarkable that organo-transition metal complexes materials showed strong 8.9 and 9.9 wt% hydrogen adsorption capabilities. Such endeavours are imperative to usher in a sustainable H2 powered future. This comprehensive review explores various materials for physisorption and chemisorption-based hydrogen storage, providing in-depth insights and pertinent comparisons to highlight their potential for effective hydrogen storage solutions
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Response surface optimization and support vector regression modeling of microwave-assisted essential oil extraction from cumin seeds
(Elsevier BV, 2024-02)
Ali Asif Khan
;
Sadaf Zaidi
;
Fazil Qureshi
;
Mohammad Yusuf
;
Abdullah A. Al-Kahtani
The current research involved creating models using Response Surface Methodology (RSM) and Support Vector Regression (SVR) to forecast the amount of extractable essential oil that can be obtained from powdered cumin seeds. Influence of microwave power (140–280–420–560–700 W), amount of water (500–600–700–800–900 ml), duration of distillation (30–45–60–75–90 min) and soak time (15–30–45–60–75 min) on essential oil yield were investigated. Microwave Assisted Extraction (MAE) allowed higher recoveries compared to conventional Soxhlet extraction, without altering the chemical components of the extract. A five-level four FCC experimental design was developed using Minitab (15.1.20.0). A total of 31 runs were performed in microwave-assisted extraction apparatus. Experimental data obtained was then used for developing RSM and SVR models for the prediction of the yield of essential oil. The optimum conditions for maximum yield of cumin oil were given by RSM. Maximum yield of 3.4 ml (0.017 ml/g) was found at 140 W of microwave power, 500 ml of water, 90 min duration of distillation, and 15 min of soak time. In this work, epsilon SVR with RBF kernel was used. The grid search (depth-first search) methodology was applied for tuning the values of epsilon, gamma, and cost using the LIBSVM module on the MATLAB interface. The statistical parameters namely, average absolute relative error (AARE), coefficient of determination (R2), standard deviation (SD), and root mean square error (RMSE) were selected as the performance parameters. The developed SVR model was compared with the RSM model. The AARE values of 2.27% and 1.29%, R2 values of 0.86 and 0.99, SD values of 1.73 and 0.29, and RMSE values of 0.0284 and 0.0132 were obtained for RSM and SVR models respectively. It is found that SVR is more accurate and better tool for modeling of MAE process.
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A sustainable approach for fluoride treatment using coconut fiber cellulose as an adsorbent
(Elsevier BV, 2024-03)
Athar Hussain
;
Jaya Maitra
;
Aslam Saifi
;
Salman Ahmed
;
Jahangeer Ahmed
In developing countries like India, an economically viable and ecologically approachable strategy is required to safeguard the drinking water. Excessive fluoride intake through drinking water can lead to dental fluorosis, skeletal fluorosis, or both. The present study has been under with an objective to investigate the feasibility of using cellulose derived from coconut fiber as an adsorbent under varying pH conditions for fluoride elimination from water. The assessment of equilibrium concentration of metal ions using adsorption isotherms is an integral part of the study. This present finding indicates the considerable effect of variation of adsorbent dosages on the fluoride removal efficiency under constant temperature conditions of 25 ± 2 °C with a contact period of 24 h. It is pertinent to mention that maximum adsorption of 88% has been observed with a pH value of 6 with 6 h time duration with fluoride dosage of 50 mg/L. The equilibrium concentration dwindled to 0.4 mg/L at fluoride concentration of 20 mg/L. The Langmuir model designates the adsorption capacity value of 2.15 mg/L with initial fluoride concentration of 0.21 mg/g with R2 value of 0.660. Similarly, the adsorption capacity using Freundlich isotherms is found to be 0.58 L/g and 0.59 L/g with fluoride concentration of 1.84 mg/L and 2.15 mg/L respectively. The results from the present study confirm that coconut fiber possesses appropriate sorption capabilities of fluoride ion but is a pH dependent phenomenon. The outcomes of the study indicate the possible use of cellulose extracted from waste coconut fiber as a low-cost fluoride adsorbent. The present study can be well implemented on real scale systems as it will be beneficial economically as well as environmentally.

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