Browse
Submit Data
Databases
API
Help

Dataset Information

27 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Oxidation-enhanced thermoelectric efficiency in a two-dimensional phosphorene oxide.

ABSTRACT: We performed density functional theory calculations to investigate the thermoelectric properties of phosphorene oxide (PO) expected to form by spontaneous oxidation of phosphorene. Since thermoelectric features by nature arise from the consequences of the electron-phonon interaction, we computed the phonon-mediated electron relaxation time, which was fed into the semiclassical Boltzmann transport equation to be solved for various thermoelectric-related quantities. It was found that PO exhibits superior thermoelectric performance compared with its pristine counterpart, which has been proposed to be a candidate for the use of future thermoelectric applications. We revealed that spontaneous oxidation of phosphorene leads to a significant enhancement in the thermoelectric properties of n-doped phosphorene oxide, which is attributed to the considerable reduction of lattice thermal conductivity albeit a small decrease in electrical conductivity. Our results suggest that controlling oxidation may be utilized to improve thermoelectric performance in nanostructures, and PO can be a promising candidate for low-dimensional thermoelectric devices.

SUBMITTER: Lee S

PROVIDER: S-EPMC8448742 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Low Lattice Thermal Conductivity of a Two-Dimensional Phosphorene Oxide.

Project description:A fundamental understanding of the phonon transport mechanism is important for optimizing the efficiency of thermoelectric devices. In this study, we investigate the thermal transport properties of the oxidized form of phosphorene called phosphorene oxide (PO) by solving phonon Boltzmann transport equation based on first-principles density functional theory. We reveal that PO exhibits a much lower thermal conductivity (2.42-7.08 W/mK at 300 K) than its pristine counterpart as well as other two-dimensional materials. To comprehend the physical origin of such low thermal conductivity, we scrutinize the contribution of each phonon branch to the thermal conductivity by evaluating various mode-dependent quantities including Grüneisen parameters, anharmonic three-phonon scattering rate, and phase space of three-phonon scattering processes. Our results show that its flexible puckered structure of PO leads to smaller sound velocities; its broken-mirror symmetry allows more ZA phonon scattering; and the relatively-free vibration of dangling oxygen atoms in PO gives rise to additional scattering resulting in further reduction in the phonon lifetime. These results can be verified by the fact that PO has larger phase space for three-phonon processes than phosphorene. Furthermore we show that the thermal conductivity of PO can be optimized by controlling its size or its phonon mean free path, indicating that PO can be a promising candidate for low-dimensional thermoelectric devices.

| S-EPMC6435745 | biostudies-literature

Enhanced thermoelectric efficiency of porous silicene nanoribbons.

Project description:There is a critical need to attain new sustainable materials for direct upgrade of waste heat to electrical energy via the thermoelectric effect. Here we demonstrate that the thermoelectric performance of silicene nanoribbons can be improved dramatically by introducing nanopores and tuning the Fermi energy. We predict that values of electronic thermoelectric figure of merit ZTe up to 160 are achievable, provided the Fermi energy is located approximately 100 meV above the charge neutrality point. Including the effect of phonons yields a value for the full figure of merit of ZT = 3.5. Furthermore the sign of the thermopower S can be varied with achievable values as high as S = +/- 500 μV/K. As a method of tuning the Fermi energy, we analyse the effect of doping the silicene with either a strong electron donor (TTF) or a strong electron acceptor (TCNQ) and demonstrate that adsorbed layers of the former increases ZTe to a value of 3.1, which is insensitive to temperature over the range 100 K - 400 K. This combination of a high, temperature-insensitive ZTe, and the ability to choose the sign of the thermopower identifies nanoporous silicene as an ideal thermoelectric material with the potential for unprecedented performance.

| S-EPMC4377624 | biostudies-literature

Atomic-level investigation on the oxidation efficiency and corrosion resistance of lithium enhanced by the addition of two dimensional materials.

Project description:Understanding the oxidation and corrosion characteristics of Lithium (Li)-based systems is critical to their successful use as a solid fuel in spacecraft, powerplants, rechargeable batteries, submarines, and many other aquatic and corrosive environments. This study offers a systematic roadmap for engineering the oxidation efficiency and corrosion resistance of Li-based systems using ReaxFF-based Reactive Molecular Dynamics (RMD) simulations for the first time. First, we explored the oxidation mechanism of bare Li (Li/O2) at 1200 K, noticing that the oxidation process quickly ceases due to the creation of a passive oxide film on the Li surface. Afterward, we examined the effect of introducing graphene-oxide (GO) to the oxidation process of Li/O2. Interestingly, the inclusion of GO establishes a new reaction pathway between Li and O2, thus significantly improving oxidation efficiency. Additionally, we realized that when the concentration of GO increases in the system, the oxidation rate of Li/O2 increases considerably. As exposed to O2 and H2O, bare Li is observed to be highly corrosion-prone, while graphene (Gr)-coated Li exhibits excellent corrosion resistance, suggesting that Gr might be used as a promising corrosion-protective shield. Overall, this study is intended to serve as a reference for experimental investigations and assist researchers and engineers in designing more efficient Li-based functional systems.

| S-EPMC8981234 | biostudies-literature

Topochemical Synthesis of Two-Dimensional Transition-Metal Phosphides Using Phosphorene Templates.

Project description:Transition-metal phosphides (TMPs) have emerged as a fascinating class of narrow-gap semiconductors and electrocatalysts. However, they are intrinsic nonlayered materials that cannot be delaminated into two-dimensional (2D) sheets. Here, we demonstrate a general bottom-up topochemical strategy to synthesize a series of 2D TMPs (e.g. Co2 P, Ni12 P5 , and Cox Fe2-x P) by using phosphorene sheets as the phosphorus precursors and 2D templates. Notably, 2D Co2 P is a p-type semiconductor, with a hole mobility of 20.8?cm2 ?V-1 ?s-1 at 300?K in field-effect transistors. It also behaves as a promising electrocatalyst for the oxygen evolution reaction (OER), thanks to the charge-transport modulation and improved surface exposure. In particular, iron-doped Co2 P (i.e. Co1.5 Fe0.5 P) delivers a low overpotential of only 278?mV at a current density of 10?mA?cm-2 that outperforms the commercial Ir/C benchmark (304?mV).

| S-EPMC6972539 | biostudies-literature

Thermoelectric degrees of freedom determining thermoelectric efficiency.

Project description:For over half a century, the development of thermoelectric materials has based on the dimensionless figure of merit zT , assuming that the efficiency is mainly determined by this single parameter. Here, we show that the thermoelectric conversion efficiency is determined by three independent parameters, Zgen , τ, and β, which we call the three thermoelectric degrees of freedom (DoFs). Zgen is the well-defined mean of the traditional zT under nonzero temperature differences. The two additional parameters τ and β are gradients of material properties and crucial to evaluating the heat current altered by nonzero Thomson heat and asymmetric Joule heat escape. Each parameter is a figure of merit. Therefore, increasing one of the three DoFs leads to higher efficiency. Our finding explains why the single-parameter theory is inaccurate. Further, it suggests an alternative direction in material discovery and device design in thermoelectrics, such as high τ and β, beyond zT .

| S-EPMC8382987 | biostudies-literature

Two-dimensional silicon and carbon monochalcogenides with the structure of phosphorene.

Project description:Phosphorene has recently attracted significant interest for applications in electronics and optoelectronics. Inspired by this material an ab initio study was carried out on new two-dimensional binary materials with a structure analogous to phosphorene. Specifically, carbon and silicon monochalcogenides have been considered. After structural optimization, a series of binary compounds were found to be dynamically stable in a phosphorene-like geometry: CS, CSe, CTe, SiO, SiS, SiSe, and SiTe. The electronic properties of these monolayers were determined using density functional theory. By using accurate hybrid functionals it was found that these materials are semiconductors and span a broad range of bandgap values and types. Similarly to phosphorene, the computed effective masses point to a strong in-plane anisotropy of carrier mobilities. The variety of electronic properties carried by these compounds have the potential to broaden the technological applicability of two-dimensional materials.

| S-EPMC5496568 | biostudies-other

Thermoelectric and phonon transport properties of two-dimensional IV-VI compounds.

Project description:We explore the thermoelectric and phonon transport properties of two-dimensional monochalcogenides (SnSe, SnS, GeSe, and GeS) using density functional theory combined with Boltzmann transport theory. We studied the electronic structures, Seebeck coefficients, electrical conductivities, lattice thermal conductivities, and figures of merit of these two-dimensional materials, which showed that the thermoelectric performance of monolayer of these compounds is improved in comparison compared to their bulk phases. High figures of merit (ZT) are predicted for SnSe (ZT = 2.63, 2.46), SnS (ZT = 1.75, 1.88), GeSe (ZT = 1.99, 1.73), and GeS (ZT = 1.85, 1.29) at 700 K along armchair and zigzag directions, respectively. Phonon dispersion calculations confirm the dynamical stability of these compounds. The calculated lattice thermal conductivities are low while the electrical conductivities and Seebeck coefficients are high. Thus, the properties of the monolayers show high potential toward thermoelectric applications.

| S-EPMC5428725 | biostudies-literature

Phosphorene nanoribbon as a promising candidate for thermoelectric applications.

Project description:In this work, the electronic properties of phosphorene nanoribbons with different width and edge configurations are studied by using density functional theory. It is found that the armchair phosphorene nanoribbons are semiconducting while the zigzag nanoribbons are metallic. The band gaps of armchair nanoribbons decrease monotonically with increasing ribbon width. By passivating the edge phosphorus atoms with hydrogen, the zigzag series also become semiconducting, while the armchair series exhibit a larger band gap than their pristine counterpart. The electronic transport properties of these phosphorene nanoribbons are then investigated using Boltzmann theory and relaxation time approximation. We find that all the semiconducting nanoribbons exhibit very large values of Seebeck coefficient and can be further enhanced by hydrogen passivation at the edge. Taking pristine armchair nanoribbons and hydrogen-passivated zigzag naoribbons with width N = 7, 8, 9 as examples, we calculate the lattice thermal conductivity with the help of phonon Boltzmann transport equation and evaluate the width-dependent thermoelectric performance. Due to significantly enhanced Seebeck coefficient and decreased thermal conductivity, we find that at least one type of phosphorene nanoribbons can be optimized to exhibit very high figure of merit (ZT values) at room temperature, which suggests their appealing thermoelectric applications.

| S-EPMC4171703 | biostudies-other

Thermoelectric transport in temperature-driven two-dimensional topological insulators.

Project description:We theoretically investigate on the thermoelectric (TE) transport properties of edge and bulk states in a temperature-driven two-dimensional (2D) topological insulator (TI) realized from CdTe/HgTe/CdTe quantum wells (QWs). It is found that the temperature can effectively drive a TI phase in CdTe/HgTe/CdTe QWs. We find that the TE transport properties of 2D TI can be governed by edge states, bulk states, or their interplay, depending on driving temperature and chemical potential of the system. Moreover, we find that the TE figure of merit ZT shows a peak at relatively low temperatures due to the competition between bulk and edge transports. This peak vanishes at relatively high temperatures due to the dominance of bulk states in the TE transport. With decreasing the ribbon width of the temperature-driven 2D TI, the low-temperature ZT exhibits two peaks, among which one occurs due to the bulk-edge competition and the other occurs due to the edge-edge hybridization; while the high-temperature ZT first exhibits the bulk-state behavior and then the edge-state one, which is indicative of a bulk-to-edge transition in the TE transport.

| S-EPMC5548764 | biostudies-other

Two-dimensional semiconductors ZrNCl and HfNCl: Stability, electric transport, and thermoelectric properties.

Project description:Searching for novel two-dimensional (2D) semiconducting materials is a challenging issue. We investigate novel 2D semiconductors ZrNCl and HfNCl which would be isolated to single layers from van der Waals layered bulk materials, i.e., ternary transition-metal nitride halides. Their isolations are unquestionably supported through an investigation of their cleavage energies as well as their thermodynamic stability based on the ab initio molecular dynamics and phonon dispersion calculations. Strain engineering is found to be available for both single-layer (1L) ZrNCl and 1L-HfNCl, where a transition from an indirect to direct band gap is attained under a tensile strain. It is also found that 1L-ZrNCl has an excellent electron mobility of about 1.2 × 103 cm2 V-1 s-1, which is significantly higher than that of 1L-MoS2. Lastly, it is indicated that these systems have good thermoelectric properties, i.e., high Seebeck coefficient and high power factor. With these findings, 1L-ZrNCl and 1L-HfNCl would be novel promising 2D materials for a wide range of optoelectronic and thermoelectric applications.

| S-EPMC5725492 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data