Influence of the Hubbard U Correction on the Electronic Properties and Chemical Bands of the Cubic (m3¯m) Phase of SrTiO Using GGA/PBE and LDA/CA-PZ Approximations.

By using DFT simulations employing the GGA/PBE and LDA/CA-PZ approximations, the effects of the Hubbard U correction on the crystal structure, electronic properties, and chemical bands of the cubic phase (m3¯m) of STO were investigated. Our findings showed that the cubic phase (m3¯m) STO's band gaps and lattice parameters/volume are in reasonably good accordance with the experimental data, supporting the accuracy of our model. By applying the DFT + U method, we were able to obtain band gaps that were in reasonably good agreement with the most widely used experimental band gaps of the cubic (m3¯m) phase of STO, which are 3.

Review of Systematic Tendencies in (001), (011) and (111) Surfaces Using B3PW as Well as B3LYP Computations of BaTiO, CaTiO, PbTiO, SrTiO, BaZrO, CaZrO, PbZrO and SrZrO Perovskites.

We performed B3PW and B3LYP computations for BaTiO (BTO), CaTiO (CTO), PbTiO (PTO), SrTiO (STO), BaZrO (BZO), CaZrO (CZO), PbZrO (PZO) and SrZrO (SZO) perovskite neutral (001) along with polar (011) as well as (111) surfaces. For the neutral AO- as well as BO-terminated (001) surfaces, in most cases, all upper-layer atoms relax inwards, although the second-layer atoms shift outwards. On the (001) BO-terminated surface, the second-layer metal atoms, as a rule, exhibit larger atomic relaxations than the second-layer O atoms.

Enhancing photocatalytic overall water-splitting performance on dual-active-sites of the Co-P@MoS catalysts: a DFT study.

The rational construction of photocatalysts possesses tremendous potential to solve the energy crisis and environmental pollution; however, designing a catalyst for solar-driven overall water-splitting remains a great challenge. Herein, we propose a new MoS-based photocatalyst (Co-P@MoS), which skillfully uses the cobalt (Co) atom to stimulate in-plane S atoms and employs the phosphorus (P) atom to stabilize the basal plane by forming the Co-P bands. Using density functional theory (DFT), it was found that oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) can occur at the P site and S2 site of the Co-P@MoS, respectively, and the dual-active sites successfully makes a delicate balance between the adsorption and dissociation of hydrogen.

Overview of the Structural, Electronic and Optical Properties of the Cubic and Tetragonal Phases of PbTiO by Applying Hubbard Potential Correction.

We have performed a systematic study resulting in detailed information on the structural, electronic and optical properties of the cubic (m3¯m) and tetragonal (4mm) phases of PbTiO applying the GGA/PBE approximation with and without the Hubbard U potential correction. Through the variation in Hubbard potential values, we establish band gap predictions for the tetragonal phase of PbTiO that are in rather good agreement with experimental data. Furthermore, the bond lengths for both phases of PbTiO were assessed with experimental measurements, confirming the validity of our model, while chemical bond analysis highlights the covalent nature of the Ti-O and Pb-O bonds.

Oxygen Vacancy Formation and Migration within the Antiphase Boundaries in Lanthanum Scandate-Based Oxides: Computational Study.

The atomic structure of antiphase boundaries in Sr-doped lanthanum scandate (LaSrScO) perovskite, promising as the proton conductor, was modelled by means of DFT method. Two structural types of interfaces formed by structural octahedral coupling were constructed: edge- and face-shared. The energetic stability of these two interfaces was investigated.

First-principles calculations of 0D/2D GQDs-MoS mixed van der Waals heterojunctions for photocatalysis: a transition from type I to type II.

The fabrication of type II heterojunctions is an efficient strategy to facilitate charge separation in photocatalysis. Here, mixed dimensional 0D/2D van der Waals (vdW) heterostructures (graphene quantum dots (GQDs)-MoS) for generating hydrogen from water splitting are investigated based on density functional theory (DFT). The electronic and photocatalytic properties of three heterostructures, namely, CH-MoS, CH-MoS and CH-MoS are estimated by analyzing the density of states, charge density difference, work function, Bader charge, absorption spectra and band alignment.

Time-Dependent Density Functional Theory Calculations of N- and S-Doped TiO Nanotube for Water-Splitting Applications.

On the basis of time-dependent density functional theory (TD-DFT) we performed first-principle calculations to predict optical properties and transition states of pristine, N- and S-doped, and N+S-codoped anatase TiO2 nanotubes of 1 nm-diameter. The host O atoms of the pristine TiO2 nanotube were substituted by N and S atoms to evaluate the influence of dopants on the photocatalytic properties of hollow titania nanostructures. The charge transition mechanism promoted by dopants positioned in the nanotube wall clearly demonstrates the constructive and destructive contributions to photoabsorption by means of calculated transition contribution maps.

A novel T-CN and seawater desalination.

A structurally stable stacked multilayer carbonitride is predicted with the aid of ab initio calculations. This carbonitride consists of C3N tetrahedra, and is similar to T-carbon and thus named T-C3N. Its 2-dimensional (2D) monolayer is also carefully investigated in this work.

MD Simulation Investigation on the Binding Process of Smoke-Derived Germination Stimulants to Its Receptor.

Karrikins (KARs) are a class of smoke-derived seed germination stimulants with great significance in both agriculture and plant biology. By means of direct binding to the receptor protein KAI2, the compounds can initiate the KAR signal transduction pathway, hence triggering germination of the dormant seeds in the soil. In the research, several molecular dynamics (MD) simulation techniques were properly integrated to investigate the binding process of KAR to KAI2 and reveal the details of the whole binding event.