We investigate the solution-generating technique based on the Breitenlohner-Maison (BM) linear system, for asymptotically flat, stationary, bi-axisymmetric black hole solutions with various horizon topologies in 5D vacuum Einstein theory. We construct the monodromy matrix associated with the BM linear system, which provides a unified framework for describing three distinct asymptotically flat, vacuum black hole solutions with a single angular momentum in five dimensions, each with a different horizon topology: (i) the singly rotating Myers-Perry black hole, (ii) the Emparan-Reall black ring, and (iii) the Chen-Teo rotating black lens. Conversely, by solving the corresponding Riemann-Hilbert problem using the procedure developed by Katsimpouri et al., we demonstrate that factorization of the monodromy matrix exactly reproduces these vacuum solutions, thereby reconstructing the three geometries. These constitute the first explicit examples in which the factorization procedure has been carried out for black holes with non-spherical horizon topologies. In addition, we discuss how the asymptotic behavior of 5D vacuum solutions at spatial infinity is reflected in the asymptotic structure of the monodromy matrix in the spectral parameter space.
NiO/rGO nanocomposites have been synthesized by the hydrothermal method. The various amounts of prepared NiO/rGO nanocomposite were incorporated with perovskite material for fabricating the perovskite solar cells (PSCs). The structure of NiO/rGO-CH3NH3PbI3 based PSC is FTO/c-TiO2/m-TiO2/NiO/rGO-CH3NH3PbI3/Carbon. The present NiO/rGO-CH3NH3PbI3 based PSC obtained a power conversion efficiency (PCE) of 15.27
The four-dimensional Chern-Simons (CS) theory provides a systematic procedure for realizing two-dimensional integrable field theories. It is therefore a natural question to ask whether integrable deformations of the theories can be realized in the four-dimensional CS theory. In this work, we study TT and root- TT deformations of two-dimensional integrable field theories, formulated in terms of dynamical coordinate transformations, within the framework of four-dimensional CS theory coupled to disorder defects. We illustrate our procedure in detail for the degenerate ℰ -model, a specific construction that captures and unifies a broad range of integrable systems, including the principal chiral model.
We construct a class of regular black hole solutions of the Fan-Wang type within quasi-topological gravity (QTG) in arbitrary spacetime dimensions greater than four. In contrast to the original Fan-Wang solution, which was obtained in four-dimensional general relativity coupled to nonlinear electrodynamics, our higher-dimensional generalization does not require any matter fields. Instead, regularity is achieved purely through an infinite tower of higher-curvature corrections. We demonstrate that the Fan-Wang-type metric is a solution to the QTG field equations by explicitly determining the corresponding coupling constants for each curvature order. Within an appropriate parameter regime, the solution describes an asymptotically flat black hole spacetime with a regular center. Remarkably, even in the case of negative mass, the geometry can remain completely regular, in sharp contrast to Einstein gravity.
Copper cobaltite (CuCo2O4), a mixed-valence bimetal oxide holds great promise as an electrode material for energy storage sector; however, the bottleneck is poor electron migration, slow reaction kinetics, and relatively lower specific capacity. Hybridization with highly conductive and mechanically robust materials has proven to be an effective approach to overcome these limitations. Herein, we report the preparation of CuCo2O4 (CCO) hybridized with Mo2TiC2TX-MXene (MX) using hydrothermal synthesis. The hybrid material was systematically analysed for its structural and compositional characteristics using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Electrochemical characterization revealed that the CuCo2O4/Mo2TiC2TX-MXene (CCMX) hybrid electrode possesses a specific capacitance of 603.3 F g-1 at 3 A g-1. Additionally, the hybrid supercapacitor based on the CCMX hybrid electrode exhibits a maximum energy density of 29.4 W h kg-1 at a power density of 699.6 W kg-1. Density functional theory reveals enhanced conductivity in CCMX compared to CCO alone. Partial density of states analysis further explores the possible charge transfer between CCO and MX. The results highlight the viability of the CCMX hybrid electrode for real-world energy storage applications.
