Construction Of A New Electrogenerated Chemiluminescence System Based On Black Phosphorus Nanomaterials

In this paper,new electrogenerated chemiluminescence systems were developed by studying the electrogenerated chemiluminescence properties of black phosphorus.It mainly includes the following three parts:1.Black phosphorus quantum dots?BPQDs?with an average size of 8.2 nm were synthesized through a liquid exfoliation coupled with ultrasonic methods.The surface morphology and the thickness of the BPQDs were identified by high-resolution transmission microscopy?HRTEM?,atomic force microscopy?AFM?,and Raman spectroscopy.The electrogenerated chemiluminescence?ECL?behavior of Ru?bpy?₃²⁺was investigated at a BPQDs modified glassy carbon electrode under neutral conditions.A strong anodic ECL signal was obtained at the modified electrode in the absence of a coreactant,which is nearly three orders of magnitude larger than that at the bare electrode.Electrochemical results revealed that the oxidation process of Ru?bpy?₃²⁺can be significantly catalyzed by BPQDs,suggesting that BPQDs can act as the coreactant of Ru?bpy?₃²⁺to generate strong light emission.Dopamine could react with the oxidation product of Ru?bpy?₃ ²⁺and exhibited an apparent inhibiting effect on ECL emission.As a result,it can be sensitively detected in the range of 0.1nM to 50 nM with a detection limit of 0.022 nM.The present work revealed that BPQDs are a potential ECL platform,and which are promising in the fabrication of a novel ECL biosensor.2.Black phosphorus nanosheets?BPNS?were synthesized from BP crystals through liquid exfoliation coupled with ultrasonic methods under aqueous conditions.The morphology of the synthesized BPNS was characterized by TEM,XPS,AFM,Raman spectroscopy,UV-vis absorption and fluorescence spectroscopy,respectively.The obtained BPNS exhibited a multilayer structure and the lateral length was around300 nm,and could emit fluorescence at 380 nm.A BPNS modified glassy carbon electrode?BPNS/GCE?was fabricated and a strong anodic electrogenerated chemiluminescence?ECL?signal was obtained at the modified electrode with tripropylamine?TPrA?as a coreactant under neutral conditions.Hydrogen peroxide exhibited an apparent inhibiting effect on the anodic ECL signal,and can be sensitively detected.In the range of 1–1000 nM,the decreased ECL intensities varied linearly with the logarithm of the H₂O₂ concentration,and the detection limit was calculated as 0.96 nM?3??.The proposed modified electrode exhibited high sensitivity and good stability.The results revealed a new character of BPNS in ECL investigation,and the potential application of 2D nanocomposites in the ECL sensing field.3.Black phosphorus quantum dots?BPQDs?can react with Ru?bpy?₃²⁺to generate strong anodic electrogenerated chemiluminescence?ECL?.However,the instability and the lack of functional groups on BPQDs limit its further application in the fabrication of ECL biosensor.In the present work,uniform BPQDs-styrene-acrylamide?St-AAm?nanospheres?BSAN?are synthesized by encapsulating BPQDs into St-AAm copolymer nanospheres.Sufficient amount of BPQDs can be embedded into nanospheres,and react with Ru?bpy?₃²⁺to generate strong anodic ECL which is comparable to that of pure BPQDs.Amino group of polymer endows BPQDs the ability to connect with DNA,and can be used to fabricate ECL aptasensor for the sensitive detection of lysozyme.The proposed aptasensor shows high sensitivity,good selectivity and stability for the detection of lysozyme in the range of 0.1–100 pg mL^-11 with a detection limit of 0.029 pg mL-1?3??.The proposed method reveals the promising ECL sensing application of BP nanomaterials in the detection of various proteins.