Hydrogen Evolution Reaction Activity in MoTiCT MXene Derived from MoTiAlC MAX Phase: Insights from Compositional Transformations.

MAX phases represent a crucial building block for the synthesis of MXenes, which constitute an intriguing class of materials with significant application potential. This study investigates the catalytic properties of the MoTiAlC MAX phase and the corresponding MoTiCT MXene for the hydrogen evolution reaction (HER). Characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) revealed that despite the presence of secondary phases, the HER catalytic activity is primarily influenced by the MAX phase and its derived MXene.

Maximizing Potential Applications of MAX Phases: Sustainable Synthesis of Multielement TiAlC.

This study employs the molten-salt-shielded method to dope the TiAlC MAX phase with Nb and Mo, aiming to expand the intrinsic potential of the material. X-ray diffraction confirms the preservation of the hexagonal lattice structure of TiAlC, while Raman and X-ray photoelectron spectroscopic analyses reveal the successful incorporation of dopants with subtle yet significant alterations in the vibrational modes and chemical environment. Scanning electron microscopy with energy-dispersive X-ray spectroscopy characterizations illustrate the characteristic layered morphology and uniform dopant distribution.

2D Rhenium- and Niobium-Doped WSe Photoactive Cathodes in Photo-Enhanced Hybrid Zn-Ion Capacitors.

Designing a multifunctional device that combines solar energy conversion and energy storage is an appealing and promising approach for the next generation of green power and sustainable society. In this work, we fabricated a single-piece device incorporating undoped WSe, Re- or Nb-doped WSe photocathode, and zinc foil anode system enabling a light-assisted rechargeable aqueous zinc metal cell. Comparison of structural, optical, and photoelectric characteristics of undoped and doped WSe has further confirmed that ionic insertion of donor metal (rhenium and niobium) plays an important role in enhancing photoelectrochemical energy storage properties.

Exploring Surface and Tunneling Properties of Defect-Oriented Quasi-Graphene/Poly(vinylidene fluoride) Nanocomposite Films as Flexible 2D Materials for Electronic Applications.

Here, we demonstrate the promising tunneling property of electrons across quasi-graphene/poly(vinylidene fluoride) (PVDF) through the Coulomb blockade region. The melt-mixing technique is used to prepare such a nanocomposite by mixing a nanofiller into the polymer matrix. The structure and surface morphology are studied using X-ray diffraction and field-emission scanning electron microscopy measurements, which show defects oriented in the sample while the binding of matrix with the nanofiller remains highly conductive even upon its binding with the insulating matrix.