School Of Basic And Applied Sciences
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Item Synergistic Effect of Crystallization Control and Defect Passivation Induced by a Multifunctional Primidone Additive for High-Performance Perovskite Solar Cells(American Chemical Society, 2022-12-22T00:00:00) Saykar, Nilesh G.; Iqbal, Muzahir; Ray, Asim K.; Mahapatra, Santosh K.The ionic nature of organic-inorganic metal halide perovskites endows intrinsic defects at the surface of the polycrystalline films. Simultaneous defect passivation during the growth of perovskite films could inhibit defect formation to a great extent. Herein, the anticonvulsant drug primidone (PRM) is demonstrated as a novel additive to control the crystallization and defect passivation of perovskites. The spectroscopic measurements support theoretical predictions showing the strong interaction between active functional groups and PbI2. An amount of PRM is tuned to obtain the perfect perovskite films with improved grain size and crystallinity than their control counterparts. Efficient PbI antisite defect passivation suppresses the non-radiative recombinations, resulting in higher luminance intensity and significantly longer charge carrier lifetimes. The PRM-modified perovskite solar cells (PSCs) show a power conversion efficiency (PCE) of 18.73%, much higher than that of control PSCs (16.62%). The ambient stability of PRM-modified PSCs is meritoriously increased compared to control PSCs. The PRM-modified PSCs show stability retention of up to 85% of the initial PCE after 1000 h, while control PSCs retain only 25% of the initial PCE after 550 h. The multifunctional defect passivation approach with the PRM additive shows the effective way for the efficiency and stability improvement of PSCs. � 2022 American Chemical Society.Item High-performance symmetric supercapacitor based on activated carbon-decorated nickel diselenide nanospheres(Springer, 2022-11-11T00:00:00) Tanwar, Shweta; Singh, Nirbhay; Sharma, A.L.The vital challenge is to advance the electronic conductivity of the transition metal diselenide for their supercapacitor application. In this report, nickel diselenide nanospheres and their decoration by activated carbon are reported by a one-step, surfactant-free hydrothermal technique. The activated carbon-decorated NiSe2 nanospheres (NAC) electrode displays high electrochemical performance than pure NiSe2 nanospheres due to more active sites, enhanced conductivity, and reduced diffusion path of electrons and electrolyte ions for maximum energy storage. The NAC electrode depicts a specific capacity of about 119 C g?1 at 0.3 A g?1. The fabricated symmetric supercapacitor using an NAC electrode shows a high specific capacitance of about 282 F g?1 at 10�mV�s?1. The cycle stability of 70% for ten thousand cycles is exhibited for the fabricated symmetric supercapacitor. It manifests high specific energy of 28�W�h�kg?1 and specific power of value 980�W�kg?1 at 1 A g?1. Device applicability with load is tested at laboratory scale by glowing different color LEDs, and a panel of 26 red LEDs illuminated for 56�min effortlessly. A self-explanatory mechanism has also been proposed to make it easier to realize the readers about glowing LEDs, and their panels. � 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Synergistically modified WS2@PANI binary nanocomposite-based all-solid-state symmetric supercapacitor with high energy density(Royal Society of Chemistry, 2022-03-09T00:00:00) Iqbal, Muzahir; Saykar, Nilesh G.; Alegaonkar, Prashant S.; Mahapatra, Santosh K.The rapid development of intelligent, wearable, compact electronic equipment has triggered the need for durable, flexible, and lightweight portable energy storage devices. Nanomaterials that are capable of delivering the high specific power density and commensurate energy density are potential candidate for realizing such devices. Herein, we report the facile synthesis of a binary nanocomposite WS2@PANI by utilizing hydrothermal and physical blending techniques to assess it as an electrode material for high-performance supercapacitors. The nanocomposite electrode delivered specific capacitance >335 F g?1 @ 10 mV s?1 (two-electrode), achieving energy and power densities of ?80 W h kg?1 and ?800 W kg?1, respectively, with capacitance retention of 83% even after 5000 charge-discharge cycles @ 10 A g?1, all of which are superior to the WS2 electrode. Dunns model quantifies capacitive and intercalative contributions that showed the cumulative effect of both to realize a robust, cost-effective, and energy-efficient device. The strategically incorporated PANI broadened the electrochemical window and the device's overall performance, resulting in high specific energy density. We demonstrated that our all-solid-state symmetric supercapacitor could be used to illuminate a light-emitting diode and drive a rotary motor. We believe that our WS2@PANI binary nanocomposite will be a potential candidate for energy storage devices. � 2022 The Royal Society of ChemistryItem Bifunctional electrochemical OER and HER activity of Ta2O5 nanoparticles over Fe2O3 nanoparticles(Royal Society of Chemistry, 2023-08-23T00:00:00) Ahmed, Imtiaz; Burman, Vishal; Biswas, Rathindranath; Roy, Ayan; Sharma, Rohit; Haldar, Krishna KantaHydrogen production via electrocatalytic water splitting offers encouraging innovations for sustainable and clean energy production as an alternative to conventional energy sources. The improvement of extraordinarily dynamic electrocatalysts is of great interest for work on the performance of gas generation, which is firmly blocked due to the sluggish kinetics of the oxygen evolution reaction (OER). The development of highly efficient base metal catalysts for electrochemical hydrogen and oxygen evolution reactions (HER and OER) is a challenging and promising task. In the present work, a particle over particles of Fe2O3 and Ta2O5 was successfully produced by hydrothermal treatment. The prepared composite shows promising catalytic performance when used as an electrochemical catalyst for OER and HER in alkaline and acidic electrolytes with low overpotentials of 231 and 201 mV at 10 mV cm?2, small Tafel slopes of 71 and 135 mV dec?1, respectively, and good stability properties. The calculated electrochemical surface area (ECSA) for composites is five times higher than that of the original oxides. The result of the OER is significantly better than that of commercial IrO2 catalysts and offers a promising direction for the development of water-splitting catalysts. � 2023 The Royal Society of Chemistry.Item Cu-Metal Organic Framework Derived Multilevel Hierarchy (Cu/CuxO@NC) as a Bifunctional Electrode for High-Performance Supercapacitors and Oxygen Evolution Reaction(American Chemical Society, 2023-05-25T00:00:00) Abbas, Zahir; Hussain, Nissar; Ahmed, Imtiaz; Mobin, Shaikh M.The development of a MOFs-derived multilevel hierarchy in a single step still remains a challenging task. Herein, we have synthesized novel Cu-MOF via a slow diffusion method at ambient temperature and further utilized it as a precursor source for MOF-derived multilevel hierarchy (Cu/CuxO@NC, x = 1 and 2). This studies suggest that the organic ligands served as a source of an N-doped carbon matrix encapsulated with metal oxide nanoparticles which were confirmed by various characterization techniques; further BET analysis reveals a surface area of 178.46 m2/g. The synthesized multilevel hierarchy was utilized as an electro-active material in a supercapacitor that achieved a specific capacitance of 546.6 F g-1 at a current density of 1 A g-1 with a higher cyclic retention of 91.81% after 10 000 GCD cycles. Furthermore, the ASC device was fabricated using Cu/CuxO@NC as the positive electrode and carbon black as the negative electrode and utilized to enlighten the commercially available LED bulb. The fabricated ASC device was further employed for a two-electrode study which achieved a specific capacitance of 68 F g-1 along with a comparable energy density of 13.6 Wh kg-1. Furthermore, the electrode material was also explored for the oxygen evolution reaction (OER) in an alkaline medium with a low overpotential of 170 mV along with a Tafel slope of 95 mV dec-1 having long-term stability. The MOF-derived material has high durability, chemical stability, and efficient electrochemical performance. This work provides some new thoughts for the design and preparation of a multilevel hierarchy (Cu/CuxO@NC) via a single precursor source in a single step and explored multifunctional applications in energy storage and an energy conversion system. � 2023 American Chemical Society.