Prof. GUO Zheng and his co-workers in Institute of Intelligent Machines (IIM), Hefei Institutes of Physical Science realized the synthesis of Cu₂Se nanobelts and porous CuO nanobelts with highly selective sensing toward H₂S. The work has been published in ACS Applied Nano Materials.

Copper based nanomaterials have been talked a lot due to their unique properties. Especially for copper selenide (Cu₂Se) and copper oxide (CuO), as typical p-type semiconductors, they have potential applications in the fields of thermoelectric conversion, catalysis, therapy, sensors, and so on.

For porous Cu₂Se and CuO belt-like nanomaterials, their intrinsic characteristics especially for gas sensing performances are further enhanced, which is attributed to higher active surface-to-volume ratios and more channels for gas diffusion.

Accordingly, developing new strategies to prepare porous Cu₂Se and CuO nanobelts will not only enrich current copper-based nanostructures, but also further widen their potential applications.

The team synthesized Cu₂Se nanobelts by a facile cation-exchange method at room temperature, and realized the synthesis of porous CuO through a thermal-oxidization approach.

As expected, the sensor based on porous CuO nanobelts film achieved high selective sensing toward H₂S.

Obviously, porous CuO nanobelts exhibit highly selective sensing toward H₂S with a low detection limit less than 10 ppb. Moreover, they also present a good sensing repeatability, short response and recovery time.

Expectedly, the developed two-step approach can be extended to prepare other porous semiconductor metal oxide nanobelts for the fabrication of high-performance gas nanosensors.

This work was supported by the National Natural Science Foundation of China, the CASHIPS Director's Fund and the CAS Interdisciplinary Innovation Team of the Chinese Academy of Sciences.

Schematic illumination of cation-exchange synthesis of Cu₂Se nanobelts from ZnSe·0.5N₂H₄ precursor nanobelts and their thermal conversion to porous CuO nanobelts. (Image by SU Yao)