April 15, 2024

Cu2ZnSnS4-Based Electrode as an Improvement Strategy for Lithium Rechargeable Batteries: A Status Review

Maryam Hassan, Nur Imyrah, Puvaneswaran Chelvanathan, Hassan Ahmoum, Paolo Scardi, Azizan Ahmad, and Mohd Sukor Su’ait

Energy Technol. 2024, 2301173

https://doi.org/10.1002/ente.202301173

Abstract

Thermal energy storage (TES) assisted with phase change materials (PCM)sseeks greater attention to bridge the gap between energy demand and supply.PCM has its footprint toward efficient storage of solar energy. Inorganic salthydrate PCMs are propitious over organic PCMs in terms of energy storageability, thermal conductivity, andfireproof, however the major issue of super-cooling and poor optical absorbance remains. This research investigates com-mercialized inorganic salt hydrate PCM with phase transition temperature of50 °C, thermal conductivity of 0.593 W m1K which is favoured with meltingenthalpy of 190 J g1, and 2–3 °C of supercooling. Mixture of graphene: silver at aproportion of (1:1) is used as the hybrid nanomaterial to further enhance thethermal conductivity, optical absorbance, and thermal stability. Hybrid nano-composites are developed via two-step process involving direct mixing andultrasonication. Morphological behaviour, chemical stability, optical property,thermal property, thermal reliability, and stability of the developed nanocom-posite samples are experimentally analysed. As a result, sustainable TESmaterials with thermal conductivity of 0.937 W m1K, optical absorbance of 0.8,increased energy storage potential is formulated. Subsequently a numericalsimulation is conducted to illustrate the potential of the developed nanocom-posite in transfer of heat energy.RESEARCH ARTICLEwww.entechnol.deEnergy Technol.2024, 24002482400248 (1 of 13)© 2024 Wiley-VCH GmbH

March 08, 2024

Thermal Diffuse Scattering from Nanocrystalline Systems

Paolo Scardi* and Marcelo Augusto Malagutti

Cryst. Growth Des. 2024

https://doi.org/10.1021/acs.cgd.3c01507

Abstract

The thermal diffuse scattering (TDS) in X-ray diffraction (XRD) patterns contains significant information about the local lattice dynamic structure of nanocrystalline systems. Techniques such as the pair distribution function (PDF) are commonly employed to extract this information, where the correlated movement of atomic pairs remains encoded in the breadths of the PDF peaks. However, PDF techniques require a Fourier transformation of the experimental XRD data, orientationally averaging the local dynamic information, rendering it not readily distinguishable from the static component and crystallite size and shape effects. Herein, we explore the possibility of an analysis of local lattice dynamics based directly on XRD powder pattern modeling, where TDS is added to the structural model of the traditional Rietveld method. Allied with the whole powder pattern modeling approach, the crystallite shape and static components are simultaneously estimated. Two study cases of Pd nanocrystalline systems are analyzed: (i) in silico nanosphere powder simulations via molecular dynamics (MD) and (ii) synchrotron radiation XRD powder patterns of Pd nanocubes. In silico analysis points out that the TDS model provides the correct trends of the correlated atomic movement up to the ninth coordination shell. The experimental case shows that this TDS model correctly estimates the force mechanisms of the nanocrystalline Pd system. We believe that the established method and the obtained results in this study broaden the application scope of XRD for studying the dynamic properties of nanocrystalline materials.

Febraury 22, 2024

Congratulations to our PhD student Varun D.N. for winning the student travel grant to attend the International Workshop on Advanced Materials ( IWAM 2024) in Dubai, UAE, from Feb 19-21.  Additionally, he was honored with the second-best poster award at this esteemed conference.

Febraury 16, 2024

Jannuary 29, 2024

Microstructural Insights into the Transformation of Cubic, Low-Temperature, Disordered Cu2ZnSnS4 into the Tetragonal Form

S. Bette, E. Isotta, B. Mukherjee, A. Schulz, Z. Dallos, U. Kolb, Robert E. Dinnebier, and P. Scardi

J. Phys.Chem.C2024,128,1717−1727

https://doi.org/10.1021/acs.jpcc.3c07085

Abstract

Multinary earth-abundant chalcogenides, like kesterite, Cu2ZnSnS4 (CZTS), have attracted attention in sustainable energy applications like photovoltaics and thermoelectrics. Highenergy ball milling provides a facile way for the synthesis of pure cubic CZTS. This sulfide crystallizes in a sphalerite-type structure with complete occupational disorder in the cationic substructure and a considerable amount of stacking faults. Heating of the material leads to the slow and irreversible transition into disordered, tetragonal kesterite, which is associated with a significant decrease in thermoelectric properties. Hence, a deep understanding of the phase transition process and its kinetics is a prerequisite for further crystal engineering. In situ X-ray powder diffraction and Raman spectroscopy supported by density functional theory calculations and ab initio molecular dynamics simulations (AIMD) were employed to gain microstructural insights into the phase transition process. Heating leads to a growth of the crystalline domains, which is associated with a reduction of strain. The domain growth reduces the stabilization of the metastable cubic phase by nanostructuring. This eventually leads to the segregation of tin cations, which corresponds to the beginning of the transition into the tetragonal phase. AIMD simulations indicate that the presence of faulting planes promotes the tin diffusion. As stacking faults appear to be energetically less favorable in the tetragonal disordered form, the stacking fault disorder is reduced upon heating, leading to an additional strain reduction.

Jannuary 29, 2024

Environmental and energy assessment of photovoltaic-thermal system combined with a reflector supported by nanofluid filter and a sustainable thermoelectric generator
M. Sheikholeslami, Z. Khalili , P. Scardi , N. Ataollahi

Journal of Cleaner Production 438 (2024) 140659

https://doi.org/10.1016/j.jclepro.2024.140659

Abstract

This study focuses on new design of a photovoltaic-thermal (PVT) unit through the utilization of a cylindrical reflector. The integration of a thermoelectric generator layer fabricated from Cu2SnS3 (CTS) and a nanofluid spectral filter composed of a MgO-water mixture within PVT leads to performance enhancement. A mathematical approach was established involving optical features and the Finite volume approach was employed for simulation. The validity of the method was verified through comparison with experimental data. By introducing fins and a filter duct, along with a cylindrical reflector, the overall performance is enhanced by 36.3%. Adding a reflector into the finned structure leads to an overall performance improvement of approximately 5.7% and 4.7% with and without a nanofluid filter. By increasing the velocity of the filter, the electrical performance was enhanced resulting in an improvement of 37.7% when a reflector is present. Integrating a reflector, fins and filter in a combined system leads to the maximum reduction in CO2 emission with a value 2 times higher than that of conventional PV.

Jannuary 19, 2024

Computational Modeling of Hydrated Polyamine-Based Anion Exchange Membranes via Molecular Dynamics Simulation

Eleonora Tomasino, Binayak Mukherjee, Varun Donnakatte Neelalochana, Paolo Scardi, and Narges Ataollahi

ACS Appl.J. Phys. Chem. C. 2024

https://doi.org/10.1021/acs.jpcc.3c07118

Abstract

The present study aims to investigate static and dynamic properties of polyamine-based anion exchange membranes  (AEMs) using all-atom molecular dynamics simulations. The effects of the hydration level, degree of amination, and temperature on the properties of AEMs were systematically explored. The phase segregation and the formation of interconnected hydrophilic channels were visualized for different simulated membranes. Additionally, the variation of the diffusion coefficients of both water molecules and hydroxide anions as a function of the aforementioned parameters were computed, and the mechanical properties of the different membranes were studied. The results revealed that increasing the degree of amination and water uptake facilitates the transport of water and anionic species. However, this comes at the expense of the mechanical stability of the membrane due to water-induced plasticization, potentially leading to its irreversible deformation under operating conditions. We then demonstrate that a promising compromise solution between high conductivity and mechanical stability can be achieved by limiting the degree of amination to about 30%. These results furnish valuable insights into the development of improvednology.