Strain Tunable Thermoelectric Material: Janus ZrSSe Monolayer

Two-dimensional piezoelectric AlSiX2 (X = N, P, As) semiconductors with Raman activity, favorable band-gap, and high carrier mobility based on first-principles calculations

In the present work, we attempt to construct two-dimensional AlSiX2 (X = N, P, As) monolayers and examine their stabilities, Raman activity, piezoelectricity, as well as electronic/transport properties for various applications, using first-principles calculations. All three - AlSiN2, AlSiP2 and AlSiAs2 - configurations are confirmed to have good dynamic, thermal, and mechanical stabilities from their phonon spectra, ab initio molecular dynamics investigations, and attained elastic constants/cohesive energy results. The Raman spectra of the AlSiX2 monolayers are performed using the finite displacement technique to assess their vibrational properties and Raman activities. The calculated electronic band structures of the studied monolayers reveal their semiconductor behaviors. The AlSiN2 monolayer shows a direct band-gap meanwhile the AlSiP2 and AlSiAs2 monolayers exhibit an indirect band-gap. The AlSiX2 monolayers are found as piezoelectric materials with the in-plane piezoelectric effects. The AlSiN2 has the in-plane piezoelectric coefficient d11 value of 0.43 pm V-1, whereas the AlSiP2 and AlSiAs2 monolayers have the higher absolute d11 values of -0.76 and -0.71 pm V-1, respectively. Moreover, we also examine the carrier mobilities of the AlSiX2 monolayers for their transport properties by utilizing the deformation potential approach. The AlSiN2, AlSiP2, and AlSiAs2 monolayers exhibit high and anisotropic electron mobilities. The achieved mobility of electrons are 1096.01 and 1765.43 cm2 V-1 s-1 in the x direction for the AlSiN2 and AlSiP2 monolayers, respectively. AlSiAs2 shows the highest electron mobility of 2027.28 cm2 V-1 s-1 in the x direction and 1120.49 cm2 V-1 s-1 in the y direction. The findings in our study demonstrate that the AlSiX2 monolayers are potential piezoelectric semiconductors with impressive anisotropic electron mobilities and favorable band-gaps for applications in electronic, photovoltaic, optic, and piezoelectric fields.

Advances in Nanoparticle-Enhanced Thermoelectric Materials from Synthesis to Energy Harvesting: A Review

This comprehensive review analysis examines the domain of composite thermoelectric materials that integrate nanoparticles, providing a critical assessment of their methods for improving thermoelectric properties and the procedures used for their fabrication. This study examines several approaches to enhance power factor and lattice thermal conductivity, emphasizing the influence of secondary phases and structural alterations. This study investigates the impact of synthesis methods on the electrical characteristics of materials, with a particular focus on novel techniques such as electrodeposition onto carbon nanotubes. The acquired insights provide useful guidance for the creation of new thermoelectric materials. The review also compares and contrasts organic and inorganic thermoelectric materials, with a particular focus on the potential of inorganic materials in the context of waste heat recovery and power production within industries. This analysis highlights the role of inorganic materials in improving energy efficiency and promoting environmental sustainability.