Synthesis & Performance Evaluation of Hybrid Cathode Materials for Energy Storage

Research into the development of novel cathode materials for energy storage applications is progressing at a rapid rate to meet the ever-growing demands of modern society. Amongst various options, batteries are playing a vital role to replace conventional energy sources such as fossil fuels with green technologies. Among various battery technologies, lithium-ion batteries (LIBs) have been well explored and have succeeded in being adjusted with find many commercial applications. At the same time, as an alternative to LIBs, Sodium-Ion Batteries (SIBs) are also gaining popularity due to the presence of Sodium (Na) in abundance and its similar electrochemical characteristics with lithium (Li). However, SIBs are suffering from many challenges such as slow ionic movement, instability in different phases, and low energy density, etc. Many strategies in the literature have been proposed to address the aforementioned challenges of SIBs. Among them, the substitution of Na with Li to form hybrid cathode materials has turned out to be quite promising. The present work aims to investigate the effect of Na substitution with Li in a pyrophosphate framework. Towards this direction, Na(2-x) LixFeP2O7 (x=0,0.6) hybrid cathode materials were synthesized, and their structural, thermal, and electrochemical properties were studied. It is noticed that the incorporation of Li in the triclinic structure of Na2FeP2O7 has a significant effect on its thermal and electrochemical performance. This study can be considered as a baseline to develop some other pyrophosphate-based high-performance hybrid cathode materials

Electrochemical Performance of Na3V2(PO4)2F3 Electrode Material in a Symmetric Cell

A NASICON-based Na3V2(PO4)2F3 (NVPF) cathode material is reported herein as a potential symmetric cell electrode material. The symmetric cell was active from 0 to 3.5 V and showed a capacity of 85 mAh/g at 0.1 C. With cycling, the NVPF symmetric cell showed a very long and stable cycle life, having a capacity retention of 61% after 1000 cycles at 1 C. The diffusion coefficient calculated from cyclic voltammetry (CV) and the galvanostatic intermittent titration technique (GITT) was found to be ~10−9–10−11, suggesting a smooth diffusion of Na+ in the NVPF symmetric cell. The electrochemical impedance spectroscopy (EIS) carried out during cycling showed increases in bulk resistance, solid electrolyte interphase (SEI) resistance, and charge transfer resistance with the number of cycles, explaining the origin of capacity fade in the NVPF symmetric cell. Finally, the postmortem analysis of the symmetric cell after 1000 cycles at a 1 C rate indicated that the intercalation/de-intercalation of sodium into/from the host structure occurred without any major structural destabilization in both the cathode and anode. However, there was slight distortion in the cathode structure observed, which resulted in capacity loss of the symmetric cell. The promising electrochemical performance of NVPF in the symmetric cell makes it attractive for developing long-life and cost-effective batteries.Funding: This publication was financially supported by Qatar University through the internal grant-QUCG-CENG-20/21-2. This work was also supported by the Qatar National Research Fund (a member of the Qatar Foundation) through the NPRP Grant#NPRP11S-1225-170128.Scopu

SYNTHESIS AND EVALUATION OF Ti3C2 MXENE ENCRYPTED NASICON Na3V2(PO4)2F3 FLUOROPHOSPHATE AND THEIR PERFORMANCE IN A SODIUM SYMMETRIC CELL

Lithium (Li) based battery materials are facing the harsh challenges of high cost and resource limitation. Sodium (Na) based materials are a futuristic solution to the field of energy storage materials. The symmetric battery materials, in which the same material can be used as cathode and anode, provide a futuristic solution to the field of energy storage. The fluorophosphate-based NASICON material Na3V2(PO4)2F3 (NVPF), with its two redox couples, works as a perfect symmetric battery material. The low intrinsic electronic conductivity of the NVPF hinders its performance. In this work, the MXene 2D material with the properties of excellent electrical conductivity is incorporated with NVPF to overcome this drawback. This work combines the benefit of the NASICON material with the layered MXene structure and results in the MXene encrypted symmetric battery material. The NVPF with MXene encryption is a first of its kind study, and the nano material was synthesized using a facile sol-gel method using Ti3C2 MXene and was analyzed for its structural and electrochemical features and tested in a symmetric full-cell configuration. The assembled full cell gives a specific discharge capacity of 54mAhg-1 at 1C for 2wt% MXene composition and 94mAhg-1 at 1C for 5wt% MXene composition as compared to 43.75mAhg-1 for pristine NVPF with respect to cathode weight. The rate capability of the material has also been improved, as indicated by electrochemical studies. The electrochemical impedance spectroscopy results indicate lowered bulk resistances for the MXene 5wt% sample. The diffusion coefficient of Na+ during discharge was calculated as 4.14x10-9 cm2s-1 for the pristine sample and 9.57 x 10-9 cm2s-1 for the 5wt% MXene sample

Desalination in the GCC countries- a review

The Gulf Cooperation Council (GCC) countries are located in one of the most arid regions in the world with very less freshwater resources, and hence depending on desalination plants to tackle the water scarcity and satisfy the increasing water demand. However, several adverse effects are associated with the desalination process and thus many technologies are being implemented to reduce their environmental effects. In this paper, the GCC desalination plants, their capacities, socio-economic costs, the nature of the brine discharged, the energy demand and water production costs have been discussed. The review also features the different desalination policies in the GCC countries, their potential environmental impact, the emerging techniques, which reduces the negative impact of the desalination plants on the environment. Also, the different mitigation strategies to lower the environmental impacts of different conventional desalination techniques are analysed. This study has confirmed that the environmental impact assessment should be carried out before building a new desalination plant or prolonging the capacity of the prevailing one for limiting the adverse impact of the facility. The use of renewable energy in the desalination sector is recommended as an impressive idea to reduce the environmental impacts and huge energy costs associated.The authors gratefully acknowledge the support from Qatar University's IRCC research program through grant number IRCC-2021-004 and NPRP grant ( NPRP13S-0205-200263 ) for this research

Electronic waste considerations in the Middle East and North African (MENA) region: A review

Waste Electrical and Electronic Equipment or e-waste is a waste stream that has multiplied profoundly in recent years. Currently, many researchers focused on the study of e-waste. The Middle East & North Africa (MENA) is a region with similar geographical features, has a high young population, and is economically diverse. The area has seen unprecedented population growth in the last 50 years. This paper presents a review of the reported works in the field of e-waste in the MENA region. It aims to shed light on the various aspects of e-waste in the MENA region. The various methods of estimating the quantities of e-waste, how it is presently managed in the MENA, the impacts of e-waste, and the regulations compliant with MENA are covered in the review. The e-waste stream is beginning to attract attention in certain countries of the MENA in recent years. As a step to this, there are various mathematical models developed to estimate the quantity of e-waste effectively. The prime component of e-waste is mobile phones, which have penetrated very deeply into all regions of the world. The health hazards caused by e-waste stem primarily from heavy metals and halogenated plastics in them. The review found that the health impacts caused by informal e-waste handling in MENA countries are not given due attention and are not covered in the literature. Regarding the regulations on e-waste disposal, countries need to implement these regulations to control e-waste penetration effectively. 2022 The Author(s)Scopu

Utilization of symmetric electrode materials in energy storage application: A review

The development of efficient energy storage systems is an important field of research in the modern era where fossil fuels are headed toward. depletion. The invention of batteries is regarded as one of the most significant advancements in the field of energy storage. From its inception, a lot of research has been done and is still being carried out to develop novel and advanced materials that provide improved performance in terms of capacity, stability, and cost. In this context, symmetric or bipolar electrodes, which utilize the same material for the anode and the cathode, emerge as a suitable solution for battery technology. In this work, different types of symmetric electrode materials for batteries are subjected to review. The various structures, methods of synthesis, and characteristics are analyzed and presented. The Na3V2(PO4)3 (NVP) is the most widely analyzed symmetric material among all the symmetric materials. The Na-based systems are widely studied in symmetric configurations for their resource availability and price economics advantages. Aqueous and solid-state symmetric batteries are the emerging systems in symmetric batteries. This review will provide insights to battery researchers involved in bipolar material design and shed light on new emerging energy storage techniques.The authors would like to acknowledge the financial support of QU internal grant-QUCG-CENG-20/21-2. This publication was also made possible by NPRP Grant # NPRP11S-1225-170128 from Qatar National Research Fund (a member of the Qatar Foundation). Statements made here are the responsibility of the authors.Scopu

Cost-effective microwave-assisted O3- type sodium-based layered oxide cathode materials for sodium-ion batteries

In this work, phase pure and highly crystalline O3-type layered oxide material (Na1Ni0.33Mn0.33Fe0.33O2-NNMF) was developed using; (i) a conventional solid-state synthesis route and (ii) a facile microwave-assisted sol–gel technique. A comparison of structural, thermal, and electrochemical properties is presented to elucidate the usefulness of the microwave-assisted sol–gel synthesis technique. A remarkable reduction in the sintering process time is noticed in the microwave-assisted sol–gel synthesis technique without compromising on the structural, thermal and electrochemical properties when compared to the conventional solid-state synthesis route confirming its decent cost-effectiveness. It is further noticed that NNMF developed through microwave-assisted sol–gel synthesis technique demonstrates superior thermal stability and comparable electrochemical performance as compared to the same material produced through the conventional sintering process. The decent electrochemical properties induced in NNMF during the microwave-assisted sol–gel synthesis technique can be attributed to the efficient diffusion of Na+ions into/from the host structure during the intercalation/de-intercalation process as indicated by the high value of sodium diffusion coefficient (1 × 109-3.58 × 109m2s−1). The Potentiostatic Intermittent Titration Technique (PITT) analysis confirms single-phase Na+intercalation/deintercalation in the host structure, regardless of the synthesis process. Finally, EIS analysis confirms the capacity fading of the developed materials during the cycling process is essentially due to an increase in the resistance with the increasing number of cycles due to the gradual thickening of formed SEI layer. The microwave-assisted sol–gel synthesis technique can be effectively employed for the production of many families of cathode materials at competitive cost facilitating their commercialization