Anh Tuan Thanh Pham

Shrimp shell-derived porous carbon exhibits excellent dual functionality for the adsorption of organic dyes and the reduction of toxic inorganic pollutants.

Ga–In co-doped ZnO ceramics were synthesized by a solid-state reaction to elucidate the role of defect chemistry and dopant solubility in governing thermoelectric transport. Compared with pristine ZnO and Ga singly doped ZnO, the In–Ga co-doped sample (IGZO) exhibits a distinct evolution in microstructure and defect configuration. A minor fraction of Ga₂O₃(ZnO)₉ spinel phase is present, contributing to phonon scattering as part of a composite-like microstructure. Structural analyses reveal that In incorporation suppresses the formation of Ga₂O₃(ZnO)₉ spinel clusters, indicating an expansion of Ga solubility in the ZnO lattice. This solubility-assisted effect leads to a transition from secondary-phase-dominated microstructures toward point-defect-dominated configurations. The competition between spinel clusters and point defects plays a key role in determining phonon scattering behavior, where atomic-scale defects become dominant in the IGZO ceramic. At the same time, the enhanced substitution of Ga, assisted by In, modifies the electronic structure through increased carrier concentration and density-of-states effective mass. As a result, the IGZO ceramic exhibits reduced lattice thermal conductivity and modified charge transport behavior under conventional bulk processing conditions, with a ZT of 0.182 at 1073 K. These findings highlight that solubility-assisted defect engineering provides an effective pathway to tune defect hierarchy and transport mechanisms in ZnO-based thermoelectric materials.

The green hydrothermal route using Morinda citrifolia leaf extract proposes an eco-friendly pathway for ZnO nanoparticle synthesis. This approach minimizes environmental hazards during fabrication and provides sustainable antimicrobial materials.

Oxygen-vacancy-rich ZnO nanotube/Au hybrids integrate defect-assisted charge transfer with Au plasmonic hot spots for high-performance SERS sensing.

GaxZn1-xO (x = 0, 0.01, and 0.02) nanoparticles were synthesized via a simple, low-cost, and ecofriendly method using orange peel extract as a stabilizing agent. Research on such green synthesis approaches for Ga-doped ZnO remains limited. The crystal structure and thermoelectric properties of the samples were investigated. Gallium (Ga) doping improved the crystal structure and temperature-dependent electrical conductivity of ZnO. In particular, the Ga-doped ZnO sample with 2 at.% Ga (GZO-2) exhibited an electrical conductivity nearly 30 times higher than that of undoped ZnO at 1068 K. Furthermore, the power factor of this sample reached approximately 56 mW/mK2 at 1068 K, nearly twofold higher than that of undoped ZnO. Additionally, the reduced grain size enhanced grain boundary scattering, markedly decreasing thermal conductivity. Therefore, GZO-2 exhibited the highest figure of merit, approximately 2.5 times higher than that of undoped ZnO. These results highlight the novelty of using agricultural-waste-derived orange peel extract in green synthesis and demonstrate the effectiveness of Ga doping in enhancing the thermoelectric performance of ZnO through microstructural modification.