Optimizing Molecular Passivation in MAPbI Perovskites: Impact of Dipole Moments and Structural Parameters.

In the realm of perovskite materials, organic molecules situated at the A site play a critical role in stabilizing the structure through specific orientations and weak interactions with the inorganic framework. These polar interactions significantly influence the optoelectronic properties of perovskites, and the introduction of polar molecules can disrupt the inherent polarization, thereby altering the material performance. The research primarily focuses on the relationship between the length and width of these organic cations and their polar inductive effects.

Minimum Tracking Linear Response Hubbard and Hund Corrected Density Functional Theory in CP2K.

We present the implementation of the Hubbard () and Hund () corrected Density Functional Theory (DFT + + ) functionality in the Quickstep program, which is part of the CP2K suite. The tensorial and Löwdin subspace representations are implemented and compared. Full analytical DFT + + forces are implemented and benchmarked for the tensorial and Löwdin representations.

Phase Stability and Phase Transition Pathways in the Rhombohedral Phase of HfO.

Determining the stability of complex phases in HfO is fundamental to advancing its development and application as ferroelectric material. However, there is ongoing debate regarding whether the ferroelectric phase of HfO originates from the orthorhombic phase or the rhombohedral one. Using first-principles calculations with symmetry group and phonon structure analysis, we have derived multiple phase transitions and ferroelectric switching pathways for the rhombohedral phase, and analyzed their static and dynamic stability.

High-Valence Cu Induced by Photoelectric Reconstruction for Dynamically Stable Oxygen Evolution Sites.

Oxygen vacancies are generally considered to play a crucial role in the oxygen evolution reaction (OER). However, the generation of active sites created by oxygen vacancies is inevitably restricted by their condensation and elimination reactions. To overcome this limitation, here, we demonstrate a novel photoelectric reconstruction strategy to incorporate atomically dispersed Cu into ultrathin (about 2-3 molecular) amorphous oxyhydroxide (a-CuM, M = Co, Ni, Fe, or Zn), facilitating deprotonation of the reconstructed oxyhydroxide to generate high-valence Cu.

Imogolite Nanotubes and Their Permanently Polarized Bifunctional Surfaces for Photocatalytic Hydrogen Production.

To date, imogolite nanotubes (INTs) have been primarily used for environmental applications such as dye and pollutant degradation. However, imogolite's well-defined porous structure and distinctive electro-optical properties have prompted interest in the system's potential for energy-relevant chemical reactions. The imogolite structure leads to a permanent intrawall polarization arising from the presence of bifunctional surfaces at the inner and outer tube walls.