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With increasing concerns regarding the potential health risks associated with microwave‐based technology, researchers have been actively investigating materials with impressive microwave absorption properties. In this study, a synthesis and investigation of a nanocomposite, named Fe3O4/MWCNT/ZnO/PANI, consisting of magnetite (Fe3O4), multi‐walled carbon nanotube (MWCNT), zinc oxide (ZnO), and polyaniline (PANI) as a microwave‐absorbing material, was carried out for the first time. The nanocomposite was prepared through a simple physical mixing approach and demonstrated tunable microwave absorption, making it highly suitable for shielding applications. Structural analysis techniques, including X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy with energy‐dispersive X‐ray analysis (SEM‐EDAX), confirmed the presence of all components in the nanocomposite. Moreover, ultraviolet‐visible spectroscopy (UV‐Vis) further verified the formation of nanocomposite components and revealed an adjustable optical bandgap ranging from 2.86 to 3.34 eV. Impressively, the nanocomposite exhibited promising microwave absorption properties, with a minimum reflection loss (RL) of −32.66 dB for the nanocomposite containing 37.50 % PANI by weight, and a maximum electromagnetic bandwidth (EB) of 2.26 GHz for the nanocomposite containing 44.44 % PANI by weight, indicating its potential as an effective shielding material. Furthermore, a modified theory combining transmission line, Landau‐Lifshits, and Drude‐Lorentz theories was introduced to extract complex relative permittivity and permeability, providing insights into the role of polyaniline in enhancing the microwave absorption properties of the nanocomposite as measured by reflection loss (RL). [ABSTRACT FROM AUTHOR]

The interplay between structure and magnetic couplings is essential for scientific research and designing functional oxide BiFeO 3 (BFO)-CoFe 2 O 4 (CFO) heteroepitaxy on demand. Several research has been conducted to study this coupling mechanism such as by using various substrates to modify the strain state of BFO-CFO via misfit strain hence altering the magnetic anisotropy and further magnetoelectric coupling. In this present research, we investigate the effect of the composition ratio of CFO nanopillars on the magnetic properties of BFO-CFO heteroepitaxy to shed light on the relation between the strain and interfacial effect of nanopillars-matrix in this system. The difference ratio of BFO and CFO compositions in the system induces a modification of the vertical strain imposed on the BFO and CFO phases hence the interfacial coupling between them is also modified. The magnetic anisotropy of the samples varies depending upon the composition ratio of BFO and CFO phases indicating the effect of modulation of strain-state modification on magnetic coupling behavior in the BFO-CFO system. [ABSTRACT FROM AUTHOR]

The interest in CO2 conversion to value-added chemicals and fuels has increased in recent years as part of strategic efforts to mitigate and use the excessive CO2 concentration in the atmosphere. Much attention has been given to developing two-dimensional catalytic materials with high-efficiency CO2 adsorption capability and conversion yield. While several candidates are being investigated, MXenes stand out as one of the most promising catalysts and co-catalysts for CO2 reduction, given their excellent surface functionalities, unique layered structures, high surface areas, rich active sites, and high chemical stability. This review aims to highlight research progress and recent developments in the application of MXene-based catalysts for CO2 conversion to value-added chemicals, paying special attention to photoreduction and electroreduction. Furthermore, the underlying photocatalytic and electrocatalytic CO2 conversion mechanisms are discussed. Finally, we provide an outlook for future research in this field, including photoelectrocatalysis and photothermal CO2 reduction. [ABSTRACT FROM AUTHOR]

CoFe2O4 (CFO) mesocrystals were synthesized in the form of collectively connected nanosized grains with specific crystallographic orientations. Such CFO mesocrystals were found to exhibit distinctive magnetic and optical properties substantially deviating from those observed in conventional CFO single crystals or in a system composed of randomly distributed nanocrystals. In this study, the magnetic and optical properties of CFO mesocrystals having the geometry of rectangular and triangular-shaped islands were extensively investigated. The magnetic strength and anisotropy behavior of rectangular CFO mesocrystals are larger than the triangular ones embedded in the BiFeO3 (BFO) matrix. The result indicates that the orientation of CFO mesocrystals and the magnetic exchange interactions at the CFO-BFO vertical interfaces are important to tune the magnetic properties of CFO mesocrystals. The strain states among the two constituent phases and the substrate also exhibited significant variations in the oxygen vacancy concentration, which in turn plays a determinate role in the optical behavior of the samples. The CFO mesocrystals embedded in rhombohedrally structured BFO matrix having Fe3+/Fe2+ ratio of 1.71 had a slightly smaller band gap than those embedded in a tetragonally structured BFO matrix with Fe3+/Fe2+ ratio of 2.52. The present study demonstrates an intriguing pathway for exploring new opportunities based on a functional CFO mesocrystal-embedded system for practical applications in opto-magnetic-related devices such as magneto-photovoltaics, memory devices, and sensors. [ABSTRACT FROM AUTHOR]

Synthetic scaffolding for bone tissue engineering (BTE) has been widely utilized. The scaffold for BTE requires sufficient porosity as a template for bone cell development and growth so that it can be used in the treatment of bone defects and fractures. Nevertheless, the porosity significantly influences the compressive strength of the scaffold. Hence, controlling the porosity is a pivotal role to obtain a proper scaffold for practical BTE application. Herein, we fabricated the nanocomposite-based scaffold utilizing nano-hydroxyapatite (n-HA). The scaffold was prepared in combination with chitosan (Ch) and carboxymethyl cellulose (CMC). The ratios of n-HA, Ch, and CMC used were 40:60:0, 40:55:5, 40:50:10, 40:45:15, and 40:40:20, respectively. By controlling the Ch and CMC composition, we can tune the porosity of the nanocomposite. We found that the interpolation of the CMC prevails, as a crosslinker reinforces the nanocomposite. In addition, the binding to Ch enhanced the compressive strength of the scaffold. Thermal characteristics revealed the coefficient of thermal expansion decreases with increasing CMC content. The nanocomposite does not expand at 25–75 °C, which is suitable for human body temperature. Therefore, this nanocomposite-based scaffold is feasible for BTE application. [ABSTRACT FROM AUTHOR]

BiFeO3-CoFe2O4 (BFO-CFO) vertically aligned nanocomposite (VAN) thin-film promises great potentials for next-generation electronic devices. Its strong magnetoelectric, antiferromagnetic-ferrimagnetic, and structural couplings occur via large interface area interactions across the vertical surface between BFO and CFO phases; this leads to emergent exotic fundamental physics rendering its potential applications for various electronics, such as magnetic sensor, data storages or memory devices, and energy harvesting devices. The distinctive photoactivity of both BFO and CFO phases in the BFO-CFO VAN system also can generate advanced applications as photovoltaic and photocatalytic devices. Furthermore, owing to small overpotential and excellent stability in alkaline media, BFO-CFO nanocomposites becomes the next electrode in electrocatalysis devices. The BFO-CFO VAN also have been exponentially developed having various type of thin-film architectures grown on various substrates. In this present article, we review the current status of the BFO-CFO VAN thin-film and discuss the fundamental understanding as well as the technology involved in developing this material. We also address the challenges that hinder the commercialization of this material and propose some plausible solutions to encourage BFO-CFO VAN-based electronic devices to reach their maturity level. Furthermore, the potential marketability of the BFO-CFO VAN materials and devices for future consumer products is also discussed. [ABSTRACT FROM AUTHOR]

The innovation in microwave absorbing material has increased exponentially to support telecommunication technology. Fe 3 O 4 could be one candidate for absorber material; however, Fe 3 O 4 still has lower permeability at high frequency and high density; thus, it fails to meet one of MAM's ideal characteristics. In this research, we try to make an excellent microwave absorber material by combining conventional microwave absorber Fe 3 O 4 with multi-walled carbon nanotubes and TiO 2 (Fe 3 O 4 /MWCNT/TiO 2 nanocomposites). Structural characterization results strongly suggested that the Fe 3 O 4 /MWCNT/TiO 2 nanocomposites have been successfully fabricated. The nanocomposite presented superparamagnetic properties and has a band gap energy range between 2.236 and 2.255 eV, which is suitable for microwave absorbers. We found that increased TiO 2 concentration in the nanocomposite enhanced the microwave absorption performance. The maximum reflection loss of this study was 44.3 dB with thicknesses of 20 mm, in which 99% of the microwave was absorbed by Fe 3 O 4 /MWCNT/TiO 2 , indicating excellent microwave absorption performance. [Display omitted] • The innovation in microwave absorbing material has increased exponentially to support telecommunication technology. • Fe 3 O 4 as absorber material still has limitations. We combine it with MWCNT and TiO 2 to enhance their absorption properties. • The Fe 3 O 4 /MWCNT/TiO 2 has superparamagnetic behavior. Its M s decreases with the increase of TiO 2 nanoparticles. • The addition of TiO 2 to the nanocomposite resulted in higher microwave absorbing power. • The RL in this study ranged from − 4.4 to − 44.3 dB which indicate 90–99% absorption ability of the microwave. [ABSTRACT FROM AUTHOR]

In this study, we have successfully prepared Co x Fe 3-x O 4 /ZnO/graphite nanocomposites [x = 0, 0.1, 0.2, 0.3, 0.4, 0.5] as radar-absorbing materials. The X-ray diffraction characterization results signified that the crystallite size of Co x Fe 3-x O 4 in the nanocomposites increased from 8.5 nm to 11 nm as x increased. However, the crystallite sizes of ZnO and graphite were constant at around 55.1 and 25.8 nm, respectively. The presence of such phases was also detected at the wavenumbers of 400–560, 678, and 1637 cm−1, originating from M − O [M = Fe, Co], Zn–O, and C C bonds, respectively. The energy-dispersive X-ray spectra also showed the presence of Fe, Co, Zn, and C as constituents of the nanocomposites. The optical absorption of the nanocomposites was observed at a wavelength of 390 nm, showing bandgap values of 2.991–3.029 eV. The nanocomposites had superparamagnetic features, with magnetic saturation values between 12.78 and 25.27 emu/g, which decreased following the increase in x composition. Interestingly, the Co x Fe 3-x O 4 /ZnO/graphite nanocomposites attained a maximum reflection loss of −32.26 dB at the frequency of 11.82 GHz. In general, the reflection loss increased following the increase in x composition. Therefore, the prepared Co x Fe 3-x O 4 /ZnO/graphite nanocomposites can be a potential candidate as radar-absorbing materials with excellent performance. [ABSTRACT FROM AUTHOR]