Semiconducting Organic–Inorganic Nanodots Heterojunctions: Platforms for General Photoelectrochemical Bioanalysis Application

• Published in: Analytical chemistry (Washington) 2018-03, Vol.90 (6), p.3759-3765
• Main Authors: Wang, Qian, Ruan, Yi-Fan, Zhao, Wei-Wei, Lin, Peng, Xu, Jing-Juan, Chen, Hong-Yuan
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Cadmium Compounds - chemistry; Cadmium sulfide; Cadmium tellurides; Chemistry; Conduction bands; Conductivity; Electrochemical Techniques - methods; Electrodes; Energy levels; Fluorenes - chemistry; Heterojunctions; Light; Light irradiation; Molecular orbitals; Photochemical Processes; Photoelectric effect; Photoelectric emission; Polymers; Polymers - chemistry; Porphyrins - chemistry; Quantum dots; Quantum Dots - chemistry; Semiconductors; Sulfides - chemistry; Tellurium - chemistry; Valence band
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/acs.analchem.7b03852

In this study, semiconducting organic polymer dots (Pdots) and inorganic quantum dots (Qdots) were first utilized to construct the organic–inorganic nanodots heterojunction for the photoelectrochemical (PEC) bioanalysis application. Specifically, n-type CdS Qdots, p-type CdTe Qdots, and tetraphenylporphyrin (TPP)-doped poly­[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1′,3}-thiadazole)] (PFBT) Pdots were fabricated, and their energy levels, that is, their valence band (VB)/conduction band (CB) or lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) values, were also determined. Then, these nanodots were integrated to construct four types of p-n and p-p organic–inorganic nanodots heterojunctions, that is, CdS Qdots/TPP-doped PFBT Pdots, TPP-doped PFBT Pdots/CdS Qdots, CdTe Qdots/TPP-doped PFBT Pdots, and TPP-doped PFBT Pdots/CdTe Qdots, on the transparent glass electrode. Upon light irradiation, four heterojunctions exhibited different PEC behaviors with some having prominent photocurrent enhancement. With the model molecule l-cysteine (l-cys) as target, the proposed PEC sensor exhibited good performances. In brief, this work presents the first semiconducting organic–inorganic nanodots heterojunction for PEC bioanalysis application, which could be easily used as a general platform for future PEC bioanalysis building. Besides, it is expected to inspire more interest in the design, development, and implementation of various organic–inorganic heterojunctions for advanced PEC bioanalysis in the future.