Design two-in-one n-MoS2/p-Cu2S heterostructures for SERS monitoring and catalytic eliminating wastewater.

[Display omitted] • We develop a multifunctional p-n heterostructure material for SERS substrate. • Low concentrations of pollutants can be rapidly detected within 1 min. • The substrate exhibited excellent practicality in SERS detection. • CMS x has great potential to be cost-efficient wastewater purification materials. Monitoring toxic organic pollutants from water to protect the ecology of water resources is an important and challenging task. For this purpose, snowflake-like n-MoS 2 /p-Cu 2 S heterostructures with sensitivity and stability were synthesized by a simple method. The enhancement factor (EF) of 0.02MoS 2 /Cu 2 S substrate can reach 1.27 × 109 and limit of detection (LOD) is 10−12 M for methylene blue (MB) in lake water. Moreover, the 0.02MoS 2 /Cu 2 S showed excellent photocatalytic activity for degradation of organic pollutants (MB, CV, MG, R6G) which were removed with efficiencies of at least 70–99% within 24 min. This significant EF and photocatalytic performance are mainly attributed to the more "hot spots" offered by the distinctive morphology of Cu 2 S (confirmed by finite-difference time-domain (FDTD) simulation) and the increased charge-separation efficacy of p-n heterojunction owing to the 0.02MoS 2 /Cu 2 S. This study opens up new frontiers for the high-sensitivity detection and complete degradation of organic pollutants. The application of 0.02MoS 2 /Cu 2 S heterostructures to pollution problems provides a cost-effective solution for wastewater treatment. [ABSTRACT FROM AUTHOR]