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Ternary chalcogenide PbGa2Se4 with high resistivity, photosensitivity, and excellent nonlinear properties, exhibits a potential application in optoelectronic and nonlinear optical devices. However, the preparation of large‐sized pure PbGa2Se4 crystals is challenging due to the presence of peritectic reaction L+α(Ga2Se3)→PbGa2Se4${\mathrm{L}} + {{\alpha}}({G{a}_2S{e}_3}) \to PbG{a}_2S{e}_4$ and a narrow homogeneity region. Here, a "quenching‐annealing" method (quenching at 850 °C in ice water, and then annealing at 650 °C for 250 h by reheating) is developed to eliminate the PbSe second phase during the synthesis. Subsequently, the PbGa2Se4 single crystals are successfully grown using chemical vapor transport (CVT) with the I2 as the transport agent. The resulting crystal exhibits the crystal structure belonging to Fddd space group with the lattice parameters of a = 12.7192 Å, b = 21.2831 Å, and c = 21.5226 Å. Additionally, it possesses a wide bandgap (≈2.26 eV), high resistivity (6.59 × 1012 Ω·cm), and defect density calculated via space charge limited current measurement (SCLC) as 2.46 × 1011 cm−3. Photodetectors based on these as‐grown crystals demonstrate exceptional photosensitivity along with a high detectivity (3.2 × 108 Jones). [ABSTRACT FROM AUTHOR]

This work investigates the transport properties of layered black phosphorus (BP) grown by the chemical vapor transport (CVT). The electrical measurements are carried out at a temperature ranging from 300 to 2 K and a magnetic field up to 16 Tesla. The CVT‐grown BP exhibits p‐type conduction with an acceptor's 14–1.2 meV activation energy. The concentration of ionized acceptors is 1.2×1017cm−3$1.2 \times {10^{17}}{\rm{c}}{{\rm{m}}^{ - 3}}$ Moreover, the Hall mobility is found to be 138 cm2V−1s−1 and 4 × 104 cm2V−1s−1, respectively, at room temperature and 2 K. This work reveals the potential of CVT synthesis as a simple, nontoxic, and cheap technique to make high‐quality BP crystals with high carrier mobility ready as a solid foundation for BP single‐crystal application. [ABSTRACT FROM AUTHOR]

In this work, the ZnO:Ga (GZO) single crystals are grown by the chemical vapor transport (CVT) method. The as‐grown crystals are annealed under an oxygen atmosphere at different temperatures. The GZO crystal's structure and its optical and electrical properties are characterized by X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy, X‐ray diffraction (XRD), UV‐VIS spectrophotometry, and variable‐temperature Hall‐effect measurement. The XPS results indicate that the valence states of the majority of gallium atoms in the GZO crystals undergo transition from the metallic (Ga0) to the non‐metallic state (Gax+) with increasing annealing temperature. The Raman and XRD results show that the compressive stress along the biaxial c‐axis on GZO crystals increases gradually with annealing temperature. Meanwhile, the GZO crystal's transmittance within the range of 300 to 1000 nm is improved significantly from being opaque to about 57%. The GZO crystals exhibit a decrease in free‐carrier concentration (1020–1019 cm−3), an increase in carrier mobility (77.8–87.9 cm2/V−1s−1) and resistivity (10−4–10−2 Ω·cm). The annealed GZO crystal's carrier concentration is practically independent of temperature (90–300 K). These results show that the free‐carrier concentrations are affected by the change of valence states in gallium atoms present in the GZO crystal. [ABSTRACT FROM AUTHOR]