In 2D semiconductors, doping offers an effective approach for modulating their structural and electronic properties-owing to the creation of newly formed chemical bonds and bond relaxation. By means of density functional theory (DFT), we systematically explored the electronic properties of monolayer MoS₂ doped with X-atoms (X comprises of metals Li, Be, Al; metalloids B, Si; non-metals (NMs) C, N, P, O and the NM atoms belonging to halogen group (F, Cl)). The bonding nature of the host structures with the doped elements have been determined using electron localization function (ELF). Phonon spectra calculations are performed to distinguish between the dynamically stable and unstable systems. The band gap of MoS₂ stands divided into smaller values in a variety of magnitude depending on the dopant site and the nature of the substituted atom. The results show that halogen non-metals exhibit n-type conduction in both the (Mo- and S-rich) environments. Thus, substitutional doping of impurity atoms belonging to different groups can successfully tune the band gap of MoS₂ to the desired level for its useful applications in semiconducting electronic devices in addition to other interesting information on the nature of doping, which could be adopted to dope other 2D-TMDs to tailor their electronic and optical characteristics for more efficient electronic devices.

DFT predicts stable boron arsenide-Janus monolayer heterostructures with tunable bandgaps, high light absorption, and good carrier mobility, making them ideal for photocatalytic water splitting.

Electrochemical CO₂ reduction reactions can lead to high value-added chemical and materials production while helping decrease anthropogenic CO₂ emissions. Copper metal clusters can reduce CO₂ to more than thirty different hydrocarbons and oxygenates yet they lack the required selectivity. We present a computational characterization of the role of nano-structuring and alloying in Cu-based catalysts on the activity and selectivity of CO₂ reduction to generate the following one-carbon products: carbon monoxide (CO), formic acid (HCOOH), formaldehyde (H₂C=O), methanol (CH₃OH) and methane (CH₄). The structures and energetics were determined for the adsorption, activation, and conversion of CO₂ on monometallic and bimetallic (decorated and core@shell) 55-atom Cu-based clusters. The dopant metals considered were Ag, Cd, Pd, Pt, and Zn, located at different coordination sites. The relative binding strength of the intermediates were used to identify the optimal catalyst for the selective CO₂ conversion to one-carbon products. It was discovered that single atom Cd or Zn doping is optimal for the conversion of CO₂ to CO. The core@shell models with Ag, Pd and Pt provided higher selectivity for formic acid and formaldehyde. The Cu-Pt and Cu-Pd showed lowest overpotential for methane formation.

Owing to their small band-gap characteristics, two-dimensional transition metal dichalcogenides (TMDCs) have garnered a lot of attention. Herein, we studied the electronic as well as structural properties of doped monolayered MoSe₂ with different dopants at the selenium (Se) site employing the density functional theory (DFT) using generalized gradient approximation (GGA). To ascertain bonding nature electron localization function (ELF) was used and Phonon spectra computations were done for dynamical stability tests. We systematically explored the electronic properties of monolayer MoSe₂ doped with X-atoms (X comprises of metals Li, Be, Al; metalloids B, Si; non-metals (NMs) C, N, P, O and the NM atoms belonging to halogen group (F, Cl). We compared our outcomes with available experimental and other calculated results in the literature. The appearance of impurity lines in the energy gap causes to diminish the band gaps of doped MoSe₂. The change in doping site and dopant element results in a significant reduction in the bandgap of doped MoSe₂. To gain more insight into the electronic properties of X-doped MoSe₂ monolayer, the partial density of states (PDOS) of the dopants and neighbour Mo atoms are attached to the band structures. Our results give pleasing data regarding the optimization of bandgap which shows that halogen dopant provided n-type doping while the rest of the elements provided p-type doping in MoSe₂, which helps to understand the electrical conductivity in addition to their utilization in semiconductor and other optoelectronic devices. We are optimistic that the findings in this work will help experimentalists to carry out their research on a real-world application, which will also widen the investigation of transition-metal dichalcogenides (TMDs) in other sectors.

The electronic and the magnetic properties of Cr-doped wurtzite cadmium sulfide (Cd_1-x Cr _x S) at different concentrations (x = 12.5% and 6.25%) are investigated in the frame work of the generalized gradient approximation (GGA), its extension through on-site Hubbard U interactions (GGA+U), and the Tran Blaha modified Becke-Johnson (TB-mBJ) potential. The ferromagnetic exchange interactions between Cr-Cr atoms via S atoms are studied. The magnetic moments on these atoms are studied in detail by using different charge analysis techniques. The p-d hybridization reduces the local magnetic moment on Cr from its free space charge value and produces a small local magnetic moment on the nonmagnetic Cd and S host sites. Cr-doped CdS provides a half-metallic semiconductor.