Mohammad Nasir
@hmlab.modoo.at
Postdoctoral Resaercher
Dankook University
RESEARCH, TEACHING, or OTHER INTERESTS
Materials Science, Energy, Electrochemistry, Materials Chemistry
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Mohammad Nasir, Jun Seo, Jun Seo Park, and Hee Jung Park
Elsevier BV
Mohammad Nasir, Ji Young Park, Pilwon Heo, Kyoung Hwan Choi, and Hee Jung Park
Wiley
AbstractLi7La3Zr2O12 (LLZO) solid electrolyte (SE) is a potential candidate for developing safe and economically all‐solid‐state batteries (ASSBs) owing to its high Li‐ion conductivity and electrochemical stability against lithium anodes. However, poor stability and significant reduction in conductivity when exposed to air, limit its practical use. Herein, a unique two‐step sintering approach is designed to tailor the microstructure of LLZO that can withstand extended air exposure. The record high Li‐ion conductivity (≈1.7 mS cm−1 at 25 °C) is obtained for coarse‐grained Li6.25Ga0.25La3Zr2O12 (GLLZO) samples, whereas fine‐grained samples exhibit a relatively lower yet still substantial conductivity (≈1.3 mS cm−1). However, coarse‐grained samples are vulnerable to atmospheric attacks, forming larger Li2CO3 on the surface, leading to spontaneous cracking and significantly reduced conductivity (≈4 order). Despite these limitations, coarse‐grained samples can still be good SE for ASSBs under certain conditions. Interestingly, fine‐grained samples maintain structural integrity and Li‐ion conductivity even after prolonged exposure to air. The differing transport and stability behaviors are attributed to variations in the bulk compositions originating from distinct sintering mechanisms. These findings represent a significant step toward achieving air‐stable, highly conductive solid electrolytes with normal grain growth that will reduce interfacial resistance and improve the power density and cyclability of next‐generation ASSBs.
Ateeq Ahmed, Mohammad Nasir, Hee Jung Park, Mohammad Furquan, Mohd Hashim, and Byung-Sang Choi
Springer Science and Business Media LLC
Hee Jung Park, Jeong Min Lee, Mohammad Nasir, Seung Jo Yoo, Chel-Jong Choi, and Kimoon Lee
Elsevier BV
Mohammad Nasir, Inseo Kim, Kimoon Lee, Sang-il Kim, Kyu Hyoung Lee, and Hee Jung Park
Royal Society of Chemistry (RSC)
The transport behavior in a in LaVO3 Mott–Hubbard system is controlled by the degree of hybridization of the V 3d and O 2p states in the pure and doped systems, strongly associated with structural distortion.
Jae Myoung Oh, Mohammad Nasir, Byungki Ryu, Hyung Joong Yun, Chel‐Jong Choi, Jong‐Seong Bae, and Hee Jung Park
Wiley
AbstractThe growing industrial demand for flexible optoelectric devices has led to intensive researches on highly flexible transparent electrode materials such as graphene, reduced graphene‐oxide (r‐GO), Ag‐nanowire, and 2D metal oxides. However, except Ag‐nanowire, transparent electrode materials having optoelectric properties comparable to that of indium–tin–oxide (ITO) have not yet been developed. In this study, an ultrathin ruthenium film with a ruthenium oxide (RuO2) subsurface layer has been introduced as a flexible transparent electrode. The metallic Ru thin film is fabricated from a RuO2 nanosheet using a layer‐by‐layer coating technique, followed by thermal reduction. The thin film (≈6 nm) reveals comparable sheet resistance and transmittance as that of conventional ITO electrodes. The high transmittance (≈79%) of the metal thin film in the visible range is attributed to the presence of an oxide subsurface layer which acts as antireflection. The Ru film (with oxide subsurface layer) with figure‐of‐merit ≈3.4 × 10−4 Ω−1 shows the best performance among the thin films fabricated using a wet‐chemistry process with 2D nanosheets including graphene, r‐GO, and other metal oxides. In addition, the high mechanical flexibility of Ru thin film makes it next‐generation flexible transparent conducting electrodes, beyond graphene, r‐GO, and 2D metal oxides.
Mohammad Nasir, Arjun K. Pathak, Jackson Kubik, Devanshi Malaviya, Vaishnavi Krupa, Arup Dasgupta, and Somaditya Sen
Elsevier BV
Ateeq Ahmed, Mohammad Nasir, Mohd. Hashim, P. Tripathi, and Byung-Sang Choi
American Chemical Society (ACS)
Mohd. Hashim, Nehru Boda, Ateeq Ahmed, S. K. Sharma, D. Ravinder, Edapalli Sumalatha, Anwar Ul-Hamid, Mukhlis M. Ismail, Mohd. Chaman, Sagar E. Shirsath,et al.
Springer Science and Business Media LLC
Mohammad Nasir, Sunil Kumar, Anup Kumar Bera, Mahmud Khan, S M Yusuf, and Somaditya Sen
IOP Publishing
Abstract We report on the physical properties of Mn-rich, nonstoichiometric La2Ni0.5Mn1.5O6 ferromagnetic insulator, prepared by sol-gel method. The single-phase orthorhombic Pbnm structure for the compound was confirmed by x-ray diffraction measurements. Dc magnetization measurements revealed a high saturation magnetization of ∼5.95 μ B/f.u. at 5 K, and a ferromagnetic to paramagnetic transition at ∼162 K. Ac magnetic susceptibility measurements confirmed a broad frequency-dependent anomaly at lower temperatures indicating the presence of spin-glass type magnetic interactions. The ac susceptibility data have been discussed within the framework of the critical slowing down model and Vogel–Fulcher law, and confirmed the cluster spin-glass dynamics with a relaxation time of the order of 10−5 s. The valence of Ni and Mn ions was verified from the x-ray absorption near edge structure spectroscopy. The origin of cluster spin-glass state was discussed in terms of several possible magnetic exchange interaction pathways among Ni and Mn ions.
Mohammad Nasir, Mahmud Khan, Subhash Bhatt, Nirmalendu Patra, Dibyendu Bhattacharyya, and Somaditya Sen
IOP Publishing
Abstract The structural, electronic, and magnetic properties of a sol-gel prepared series of La2Ni1−x Sc x MnO6 compounds have been extensively studied using x-ray diffraction, x-ray absorption near edge structure, and dc magnetization techniques, respectively. The entire series was isostructural and exhibited the La2NiMnO6 double perovskite P21/n monoclinic structure. The nonmagnetic Sc3+ substitution led to the evolution of competing magnetic phases in La2Ni1−x Sc x MnO6. The substitution also caused an increase in lattice parameters, cell volume, and bond lengths. Consequently, Sc3+ dilution resulted in a dramatic decrease in Curie temperature, suggesting a reduction in the strength of the Ni2+–O2−–Mn4+ superexchange ferromagnetic interaction. The Sc3+ substitution generated antisite defects, which significantly suppressed the saturation magnetization of the system. The competing magnetic interactions observed in the La2Ni1−x Sc x MnO6 system are discussed in terms of cation disorder, cation valances, and changes in the bond lengths/angles, caused by the Sc3+ substitution.
Mohammad Nasir, Mahmud Khan, E. G. Rini, Sunday Arome Agbo, and Somaditya Sen
Springer Science and Business Media LLC
Prashant Kumar Mishra, Saniya Ayaz, Gaurav Bajpai, Mohd. Nasir, Prashant Gupta, and Somaditya Sen
AIP Publishing
Mohammad Nasir, Mahmud Khan, Sunday Arome Agbo, Subhash Bhatt, Sunil Kumar, and Somaditya Sen
IOP Publishing
The double perovskite La2FeMnO6 is ideally expected to be a ferrimagnet with a low saturation moment of 1 μB/f.u. Inhomogeneity in the Fe/Mn sites, along with other lattice disorders, can modify the exchange interactions in the material and result in a net saturation moment of more than 1 μB/f.u. Here, the origin of complicated magnetic behavior is examined of a pure phase La2FeMnO6 sample prepared by the sol-gel method. XRD analysis established that the material crystallizes in the orthorhombic Pbnm symmetry. The comprehensive analysis of x-ray photoelectron spectroscopy, x-ray near edge structure, and magnetic measurements acknowledge an antiferromagnetic coupling between Fe3+ and Mn3+ cations, thereby, resulting in the ferrimagnetic ground state for La2FeMnO6. The magnetic hysteresis loop obtained at 5 K shows a large coercivity of ∼820 Oe and a saturation moment of 1.6 μB/f.u., hinting at partial B-site ordering in La2FeMnO6. The ac susceptibility and dc magnetization measurements indicate the existence of magnetic glassy states (of cluster-glass type) with two distinct dynamical freezing points at ∼27 and 92 K, along with a Griffiths-like phase in the material. The experimental results are discussed taking several possible exchange interactions among Fe3+ and Mn3+ ions in the system into consideration. The magnetic complexity of this system makes it attractive for fundamental research and technological applications.
E.G. Rini, Ananta Paul, Mohammad Nasir, Ruhul Amin, M.K. Gupta, R. Mittal, and Somaditya Sen
Elsevier BV
Ananta Paul, Mohammad Nasir, Prashant Kumar Mishra, E. G. Rini, and Somaditya Sen
AIP Publishing
Double perovskite materials provide the versatility of interesting physical properties and applications. Among double perovskites, La2NiMnO6 has received scientific attention due to its field-induced magnetic and dielectric properties near room temperature. In the present study, polycrystalline La2Ni0.5Al0.5MnO6 double perovskite has been prepared via a standard Pechini sol-gel method followed by high-temperature sintering. The effect of Al substitution on structural and dielectric characteristics of La2Ni0.5Al0.5MnO6 was examined. The sample crystalizes in the monoclinic symmetry with P21/n space group. The dielectric analysis showed that the giant dielectric constant in La2Ni0.5Al0.5MnO6 in association with relaxor-like behavior originating from the polar arrangement of electrons or polarons due to mixed-valent Ni2+,3+/Al3+, and Mn3+,4+ cations.
E. G. Rini, Ananta Paul, Mohammad Nasir, Bungkiu Kissinquinker, Prashant Kumar Mishra, and Somaditya Sen
AIP Publishing
Bungkiu Kissinquinker, Mohammad Nasir, Ananta Paul, Prashant Kumar Mishra, and Somaditya Sen
AIP Publishing
Mohammad Nasir, Sunil Kumar, N. Patra, Md A. Ahmed, D.K. Shukla, E.G. Rini, D. Bhattacharya, S.N. Jha, and Somaditya Sen
Elsevier BV
Mohd. Nasir, Mahmud Khan, Subhash Bhatt, Anup Kumar Bera, Mohammad Furquan, Sunil Kumar, Sk. Mohammad Yusuf, Nirmalendu Patra, Dibyendu Bhattacharya, Shambhu Nath Jha,et al.
Wiley
Among multifunctional double perovskite oxides, La2NiMnO6 has recently drawn significant attention due to its importance both in terms of understanding of fundamental physics and potential for device applications. The relative alteration in Ni:Mn ratio strongly influences the structural and magnetic properties of La2NiMnO6. The cation ratio and degree of cation order significantly affect the magnetic coupling of the two B‐site cations in these compounds. In the present study, La2Ni1−xMn1+xO6 (x = −0.25, 0, 0.25) samples with different Ni:Mn ratio have been prepared using sol–gel method and modifications of the above physical properties from that of a stoichiometric sample of La2NiMnO6 are discussed. The crystalline structures of the samples varied with different ionic ratios. While all samples exhibited ferromagnetic behavior, long‐range Ni/Mn magnetic ordering was detected in selected samples only. The experimental values of saturation magnetization were smaller than the theoretical spin‐only moments, which suggests a less ordered state for all samples. Due to an increased antiferromagnetic interaction caused by antisite disorders, the saturation magnetization decreases while the coercive field increases with decreasing Mn content.
Mohd Nasir, Mahmud Khan, Sunil Kumar, Subhash Bhatt, Nirmalendu Patra, Dibyendu Bhattacharya, Shambhu Nath Jha, Sajal Biring, and Somaditya Sen
Elsevier BV
Mohd Nasir, Sunil Kumar, Nirmalendu Patra, Dibyendu Bhattacharya, Shambhu Nath Jha, Dharma R. Basaula, Subhash Bhatt, Mahmud Khan, Shun-Wei Liu, Sajal Biring,et al.
American Chemical Society (ACS)
Homogeneous solid solutions of sol–gel-prepared R2NiMnO6 (R = La, Pr, Nd, Sm, Gd, Tb, Dy, Y, and Ho) double perovskites crystallize in a B-site-ordered monoclinic structure (P21/n space group). Mon...
Mohd. Nasir, Asokan Kandasami, and Somaditya Sen
Author(s)
Mohd. Nasir, Saniya Ayaz, Sunil Kumar, Asokan Kandasami, and Somaditya Sen
Author(s)
Among multifunctional La2BB’O6 (B/B’ are transition metals) double perovskites, La2NiMnO6 has recently received significant attention due to its rich physics and prospects in technological applications. In the present study, La1.80Y0.20NiMnO6 was synthesized using sol-gel method. Le Bail profile analysis of room temperature X-ray diffraction data emphasized on the formation of single phase monoclinic (P21/n) La1.80Y0.20NiMnO6 ceramics. Temperature dependent dielectric spectroscopy shows relaxor-like behavior with giant dielectricity of the order of ∼104.
Mohd. Nasir, Rakibul Islam, Md. A Ahmed, Saniya Ayaz, Gautham Kumar, Sunil Kumar, C. L. Prajapat, Frederick Roussel, Sajal Biring, and Somaditya Sen
The Royal Society
Single phase, sol–gel prepared Cu 1 –x Fe x O (0 ≤ x ≤ 0.125) powders are characterized in terms of structural, electronic and magnetic properties. Using dielectric and magnetic studies we investigate the coupling of electron and spin. The electrical conductivities and activation energies are studied with increasing Fe content. Modelling of experimental conductivity data emphasizes a single hopping mechanism for all samples except x = 0.125, which have two activation energies. Hole doping is confirmed by confirming a majority Fe 3+ substitution of Cu 2+ in CuO from X-ray photoelectron spectroscopy studies (XPS). Such a substitution results in stabilized ferromagnetism. Fe substitution introduces variation in coercivity as an intrinsic magnetic property in Fe-doped CuO, and not as a secondary impurity phase.