Search

ZSSG (ZnSSe/rGO) composites are prepared by a hydrothermal method. The structure, morphology and material properties are investigated by various tests. Compared to ZnSe, the diffraction peaks of ZnSSe are moved to a larger angle and located between cubic phase ZnSe and cubic phase ZnS. The photocurrent density of ZSSG20 with 20 wt.% graphene is 2.17×10−5 A cm−2, which is 8.9 times higher than that of pure ZnSSe. ZSSG20 has the minimum charge transfer resistance and highest carrier density. The decreased fluorescence intensity in PL spectra indicates that graphene can effectively prevent the recombination of electron‐hole pairs. [ABSTRACT FROM AUTHOR]

S‐graphene quantum dots (GQDs), N‐GQDs, P‐GQDs, and Cl‐GQDs are prepared by a solution chemistry method and further incorporated with ZnxCd1−xSe by one‐step hydrothermal method. In the previous study, ZnxCd1−xSe reached the optimal photoelectric performances at the Zn/Cd ratio of 0.9:0.1, so the Zn0.9Cd0.1Se were combined with doped GQDs (D‐GQDs) to form Zn0.9Cd0.1Se/doped‐GQDs. The influence of GQDs doped with different elements on the photoelectric properties of Zn0.9Cd0.1Se composites is discussed. Compared with pristine Zn0.9Cd0.1Se, Zn0.9Cd0.1Se/Cl‐GQDs, and Zn0.9Cd0.1Se/P‐GQDs can improve the photocurrent response and current intensity, therein, Zn0.9Cd0.1Se/Cl‐GQDs reaches the lowest interfacial charge transfer resistance and the highest photocurrent response of 5.48 × 10−6 A cm−2. Mott–Schottky analysis shows that the fitting slope of Zn0.9Cd0.1Se/Cl‐GQDs composites is significantly lower than that of Zn0.9Cd0.1Se/GQDs with other doped elements. The results indicate that Zn0.9Cd0.1Se/Cl‐GQDs composites has the largest carrier density, which is beneficial to charge conduction. [ABSTRACT FROM AUTHOR]

In this study, tin dioxide with vacancies (SnO x) was compounded with three-dimensional reduced graphene oxide (3D RGO) to obtain SnO x /3D RGO. The morphology, optical properties and structural composition of SnO x /3D RGO were analyzed by a series of techniques, and the photoconductive properties of the SnO x /3D RGO composites with different mass fractions of RGO were investigated. The photocurrent density of SnO x /3D RGO at 3D RGO mass fraction of 1.5 % reached a maximum value of 2.77 × 10−4 A/cm2, which was about twice and 1.2 times as large as that of SnO x and SnO x /2D RGO (two-dimensional reduced graphene oxide), respectively. In the linear scanning voltammetry and Mott-Schottky analysis results, SnO x /3D RGO exhibited the highest photocurrent (6.34 × 10−3 A/cm2) intensity at 1.0 V bias and the largest carrier density (2.61 × 1021cm−3). This was due to the fact that RGO played a charge transfer role in the composite material in both 2D and 3D structures. In contrast, the porous 3D RGO could connect separate lamellae, which prevented the aggregation of layers and enhanced the electron transfer, thus exhibiting superior performance than 2D graphene. [ABSTRACT FROM AUTHOR]