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A novel high efficient p-n heterostructure photocatalyst is well designed and firstly realized on coupling electrospun TiO2 anatase/rutile mixed-crystal nanorods (T-A/R-NRs) and p-type ternary Cu3SnS4 (CTS), which is a hot photosensitive material in photovoltaics but rarely attracted in photocatalysis. Such configured CTS@T-A/R-NRs shows 2.02 eV band-gap and are demonstrated to be more efficient in photocatalytic degradation. The optimized CTS@T-A/R-NRs with 24 h hydrothermal reaction possesses a superior degradation rate of 1.3980 h−1, which is 2.5 and 4.3 times than T-A/R-NRs (0.5490 h−1) and CTS (0.3240 h−1). It is mainly attributed to the better morphology for high light-harvesting, the established built-in electric field at p-n interfaces and special anatase/rutile mixed-crystal structure of TiO2 for efficient separation of photogenerated charges. The study indicates a promising strategy in designing potential nanostructures to simultaneously achieve high efficient photocatalytic degradation and photovoltaic conversion.

Lanthanum ferrite (LaFeO3) and Co-doped LaFeO3 nanofibers with perovskite-type structure had been synthesized via electrospinning. The structure and morphology of the nanofibers were characterized by various techniques. The as-prepared products combined the advantages of well crystallinity and the surface of samples was concave-convex and rough. In addition, the crystalline size of LaFeO3 decreased after Co doping. The gas-sensing properties of two samples were measured, Co-doped LaFeO3 presented good selectivity and high response toward acetic acid compared to pure LaFeO3 nanofibers. The results demonstrated that Co-doped LaFeO3 nanofibers could be used as a promising material for selective detection of acetic acid.

ZnO/SnO 2 and Pr-doped ZnO/SnO 2 nanoflowers were fabricated through a facile two-step method. The samples were characterized by XRD, EDX, XPS, SEM and TEM analysis. The gas sensing behaviors of the sensors were systematically investigated. Compared with ZnO/SnO 2 samples, Pr-doped ZnO/SnO 2 exhibit improved sensing performance at 200 °C, and the sensors was proved to be excellent in selectivity to methanol. The methanol sensing mechanism of Pr-doped ZnO/SnO 2 nanoflowers is discussed, too. This work combines compounding and doping, which is very innovative and challenging.

Uniform Zn 2 SnO 4 solid and hollow microcubes are synthesized via hydrothermal method followed by an annealing process in air. The morphology and structure were characterized by SEM, TEM and XRD. In addition, a possible formation mechanism of the hollow microcubes is discussed. The hollow Zn 2 SnO 4 microcubes were found to exhibit higher and quicker response-recovery traits than these of solid nanocubes. Under the optimum operating temperature (260 °C), the response of hollow microcubes sensor to 200 ppm acetone is 141.7, which is 3 times larger than that of solid nanocubes (41.9). The significant decrease in response-recovery time is attributed not only to the surface accessibility allows by the hollow architectures, but also by numerous interweaving petal-like constructs of the nanoflowers.

Hematite (α-Fe2O3) hollow spheres were prepared by a one-step hydrothermal reaction without template and used to fabricate the gas sensors. Structure and morphology of the product were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results indicated that the α-Fe2O3 hollow spheres were composed of nanoparticles with the diameter of 50–70 nm, and the average diameter of α-Fe2O3 hollow spheres was 250 nm. The sensor based on α-Fe2O3 hollow spheres exhibited excellent sensing performance to methanol at 280 °C, and the response can be reached at 25 when the concentration as low as 10 ppm. In addition, sensing mechanism of the sensor towards α-Fe2O3 hollow spheres was investigated.

Cactus-like NiO was successfully synthesized by adjusting reaction time of a simple hydrothermal approach. The different morphologies of the NiO samples obtained by different reaction time were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM). And the gas-sensing performance of these products was studied, too. The results indicated that the sensor based on the cactus-like NiO nanostructures obtained by choosing appropriate reaction time showed much better sensing properties than other samples. The response of the sensor based on cactus-like NiO was about 13.51–100 ppm acetone at a working temperature of 260 °C, and the response and recovery time was 24 and 39 s, respectively. The improvement gas sensing properties based on cactus-like NiO sensor may be due to the unique structures, the good crystallization and large surface area.

Biomorphic pure ZnO and porous CeO 2 –ZnO hollow fibers have been fabricated using cotton as biotemplates. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET). XRD results indicate that the CeO 2 –ZnO sample is well crystallized and shows a mixed phase of CeO 2 and ZnO. Compared with pure ZnO, the CeO 2 –ZnO sensor exhibits much better response to ethanol with high sensitivity and good selectivity at 260 °C, which is mainly contributed to the increasing of active surface area and gas diffusion.