Distinctive Extrinsic Atom Effects on the Structural, Optical, and Electronic Properties of Bi₂S_3-xSe_x Solid Solutions

Abstract

For many decades, bulk Bi2S3, a key low-bandgap metal chalcogenide semiconductor, has lagged behind in terms of potential applications due to its poor electrical properties. As such, controlling size extrinsic atom interactions in this material might emerge as a viable route to enhance its poor electrical properties. Here, we report the hydrothermal synthesis, structural characterization, and optoelectronic properties of Bi2S3‑x Se x solid solutions. Optical characterizations show a decrease in the bandgap of Bi2S3 nanowires as a function of Se concentrations. Furthermore, ensemble electrical transport measurements suggest a pronounced increase in the electrical properties of Bi2S3 nanowires upon Se incorporation. This study points to the importance of carefully controlling the stoichiometry and sizes in Bi2S3 as a way to favorably tune its optoelectronic properties.

Semiconducting to Metallic Electronic Landscapes in Defects‐Controlled 2D π‐d Conjugated Coordination Polymer Thin Films

“…[ 20,45 ] We also determined the activation energy ( E a ) for these Cu‐BHT thin films. The E a value has been determined using the Arrhenius relationship as follows [ 46 ] where σ is the electrical conductivity, σ o is a pre‐exponential factor, E a is the activation energy, k is the Boltzmann's constant, and T is the temperature. By graphing the logarithm of the electrical conductivity (log σ) versus the reciprocal of temperature (1/ T ) and by using Equation (3), the E a value for Cu‐BHT thin films prepared using the V–V interfacial CVD polymerization growths has been estimated to be 0.15 meV.…”

Synchrotron X‐Ray Absorption Spectroscopy and Electrochemical Study of Bi2O2Se Electrode for Lithium‐/Potassium‐Ion Storage

“…As shown in Figure 4 a, Bi L III ‐edge XANES spectra were collected for Bi 2 O 2 Se, Bi 2 O 2 Se/G composite, Bi reference, and Bi 2 O 3 reference, with the absorption edge feature probing the excitation of an electron from the 2p 3/2 orbital to the empty 6d orbitals based on the dipole selection rules (Δ l = ±1). [ 24 ] The absorption edge (defined as halfway up the edge step, at xµ[E] = 0.5) of Bi 2 O 2 Se and Bi 2 O 2 Se/G nearly overlaps with that of Bi 2 O 3 , indicating that the formal valence state of Bi element in Bi 2 O 2 Se is also trivalent. In comparison with Bi 2 O 3 , the white‐line peak of Bi 2 O 2 Se locates at lower photon energy value, indicating longer average BiO bond length in Bi 2 O 2 Se, according to the empirical rule that the photon energy value of the white‐line peak are inversely correlated with the bond length.…”

“…As shown in Figure 4a, Bi L III -edge XANES spectra were collected for Bi 2 O 2 Se, Bi 2 O 2 Se/G composite, Bi reference, and Bi 2 O 3 reference, with the absorption edge feature probing the excitation of an electron from the 2p 3/2 orbital to the empty 6d orbitals based on the dipole selection rules (Δl = ±1). [24] The absorption edge (defined as halfway up the edge step, at xµ[E] = 0. Se, according to the empirical rule that the photon energy value of the white-line peak are inversely correlated with the bond length.…”

Heterostructured ferromagnet–topological insulator with dual-phase magnetic properties

“…4(b)), an increase in the thickness of Bi 2 Se 3 empties the Se p state, as reected by the increase in the intensity of peak D. This reects an increase in the contribution of Bi to bonding in these structures. 49,51 The multiple scattering of peak E presents a slight shi towards higher energies, mainly due to changes in the local geometry around the Se atoms. 49,52 This points to a stronger Bi-Se hybridization.…”