Programming a hollow core-shell CuS@CuSe heteromicrocubes synergizing superior multienzyme activity function as enhanced biosensing platforms

Introducing heterostructures combined by different building blocks (transition metal chalcogenides) enables the regulation of composition and architecture towards boosting electrocatalytic sensing performance. Herein, a successful transformation from well-defined Cu2O microcubes to hollow core-shell CuS@CuSe heteromicrocubes are performed via a template-directed in-situ sulfuration and selenization reaction at room temperature and further defined as bifunctional nanozymes to detect H2O2 reduction and DA oxidation, of which the ultrathin CuSe nanosheets vertically wrapping on hollow CuS microcube-like core created plenty of exposed active sites, rich ion-transfer channels, as well as remarkable structural stability, while the existence of interfacial effect between two components can facilitate fast ion/electron transfer to execute cooperative catalytical capacity, thus harvesting highly efficient electrochemical sensor features for catalyzing H2O2 and DA, as reflected by high sensitivity (1005.2 μA mM−1 cm−2 and 60.44 μA μM−1 cm−2), low LOD (30 nM and 0.38 nM), favorable working potential (−0.25 V and 0.20 V) as well as excellent selectivity, powerful long-term stability and outstanding repeatability/reportability. Such preeminent performance is not only superior to single CuS and CuSe counterparts and most designed nanozymes, but also creates satisfactory recoveries and expected accuracy in real human serum samples. Then, designing heterogeneous nanomaterials with matching functions and structures and investigating their potential prospects in electrocatalytic biosensors would guide the exploitation of nanozymes to fulfill the versatile requirements.