Xiaomin Huo,Honglie Shen,Wei Song,Luanhong Sun,Jaffer Saddique,Jiale Yang
A highly sensitive and selective electrochemical sensor based on porous Cu 2 ZnSnS 4 (CZTS) nanosheets is required for detecting ammonia-ammonium ions (NH 3 –NH 4 + ). Porous CZTS nanosheets synthesized by microwave irradiation method were characterized by Raman, XRD , SEM, TEM , BET, DLS and NH 3 -TPD. The porous nanosheets of CZTS-30 irradiated for 30 min with a surface area of 51.3 m 2 g −1 are significant material and possess many important active sites for NH 3 –NH 4 + oxidation . The electrode was made of a glassy carbon electrode (GCE) modified by CZTS-30. It was revealed by electrochemical measurements that there were two linear ranges for NH 3 –NH 4 + . One was the high concentration ranging from 1.0 mM to 600.0 mM ( R 2 = 0.9989) with a sensitivity of 8.29 μA mM −1 cm −2 , and the other was the low concentration between 0.1 mM and 1.0 mM ( R 2 = 0.9990) with a high sensitivity of 96.14 μA mM −1 cm −2 . It showed a detection limit of 30 μM (S/N = 10) for the sensor in NH 3 –NH 4 + solution mixed with 0.5 mM H 2 SO 4 at a fixed scan rate of 20 mV s −1 . This sensor also demonstrated desirable stability, reversibility and selectivity to NH 3 –NH 4 + . The CZTS/GCE is believed to become a new candidate structure for the electrochemical detection of NH 3 –NH 4 + .
Two-dimensional (2D) semiconducting nanomaterials have generated much interest both because of fundamental scientific interest and technological applications arising from the unique properties in two dimensions. However, the colloidal synthesis of 2D quaternary chalcogenide nanomaterials remains a great challenge owing to the lack of intrinsic driving force for its anisotropic growth. 2D wurtzite Cu 2 ZnSnS 4 nanosheets (CZTS-NS) with high-energy (002) facets have been obtained for the first time via a simple one-pot thermal decomposition method. The CZTS-NS exhibits superior photoelectrochemical activity as compared to zero-dimensional CZTS nanospheres and comparable performance to Pt counter electrode for dye sensitized solar cells. The improved catalytic activity can be attributed to additional reactive catalytic sites and higher catalytic reactivity in high-energy (002) facets of 2D CZTS-NS. This is in accordance with the density functional theory (DFT) calculations, which indicates that the (002) facets of wurtzite CZTS-NS possess higher surface energy and exhibits remarkable reducibility for I 3
− ions. The developed synthetic method and findings will be helpful for the design and synthesis of 2D semiconducting nanomaterials, especially eco-friendly copper chalcogenide nanocrystals for energy harvesting and photoelectric applications.
危险品化学品经营许可证（带存储）