Ultrasensitive SERS Detection by Defect Engineering on Single Cu2O Superstructure Particle

: A Cu2 O superstructure is constructed through a recrystallization-induced self-assembly strategy. Single Cu2 O superstructure particle exhibits an outstanding surface-enhanced Raman spectroscopy performance with the limit of detection as low as 10-9 mol L-1 and metal comparable enhancement factor (8 × 105 ) due to the synergetic effect of vacancies defect-facilitated charge-transfer process and copper vacancies defect-induced electrostatic adsorption.