We focused on the pseudo-cubic crystal structure of the chalcopyrite compounds p-type ZnSnAs2 and n-type CdSnAs2, which leads to high power-factor due to their structural symmetry. Herein, we studied the growth of a polycrystalline (Zn1-xCdx)SnAs2 (ZCTA) and its fundamental thermoelectric properties.

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Bi2Te3 is semiconductor material for thermoelectric application. It has high thermoelectric properties around room temperature. The thermoelectric materials need to have high electrical conductivity, low thermal conductivity, and high seebeck coefficient. In this study, we present the fabrication and evaluation of Bi2Te3-based thermoelectric device.

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To enable low-cost deposition and achieve a higher Ge content in Cu2Sn1-xGexS3 (CTGS) thin films, a trio-source fine-channel mist CVD method was carried out. Using Cu-Sn, S, and Ge mist sources, CTGS thin films were successfully deposited on soda-lime glass substrates. Moreover, XRD analysis confirmed the deposition of CTGS thin films on the SLG substrate.

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To reduce halogen loss and improve quality of CuBrI, bromination was performed in a bromine atmosphere using HBr. PL measurements were performed to evaluate the film quality, and it was found that the exciton emission intensity increased by bromination.

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β-phase gallium oxide (β-Ga₂O₃) is a semiconductor with a wide bandgap of approximately 4.8 to 5.04 eV, capable of transmitting light across a broad spectrum from infrared to ultraviolet. This property makes it a promising candidate for applications in wide-range devices such as power supplies, telecommunications, and high-voltage power switching. Recent measurements of the refractive index (n) in the terahertz (THz) region have revealed optical anisotropy between the b- and c-axis directions, with nc > nb. To determine whether this anisotropy persists across a wide wavelength range, we theoretically evaluate the contributions of phonons and electronic states to the refractive index.

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Nowadays, photoluminescence (PL) from semiconductors can be easily observed due to the reduction in the cost of observation equipment. However, PL cannot be observed correctly unless the equipment and observation method are properly understood. In this article, the basics of spectroscopy will be explained in order to correctly observe PL spectra.

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Thermoelectrics are an important class of technology that harvest electric power directly from heat sources. In this review, I aim to comprehensively summarize the fundamental strategies for the realization of high-performance thermoelectric materials. In addition, multinary materials have attracted considerable attention for energy applications due to their tunable physical properties. Here, I describe thermoelectric properties of multinary thermoelectric material Cu2ZnSnS4 bulk single crystal. The progresses in multinary materials will promote the use of thermoelectric technology to play a positive role in future energy solutions.

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