Microporous N,P‐Codoped Graphitic Nanosheets as an Efficient Electrocatalyst for Oxygen Reduction in Whole pH Range for Energy Conversion and Biosensing Dissolved Oxygen

• Published in: Chemistry : a European journal Vol. 24; no. 69; pp. 18487 - 18493
• Main Authors: Lin, Deqing, Hu, Chuangang, Chen, Hao, Qu, Jia, Dai, Liming
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 10.12.2018
• Subjects: Biocompatibility; Biosensors; Chemical reduction; Chemical synthesis; Chemistry; Cholecystokinin; Cornea; Cytotoxicity; Dissolved oxygen; DO biosensor; Energy conversion; Epithelial cells; metal-free electrocatalyst; N,P-codoped; Nanosheets; ORR; Oxidation; Oxygen; Oxygen reduction reactions; pH effects; Phytic acid; Polymers; Tears; Toxicity; N,P-codoped; energy conversion; metal-free electrocatalyst; DO biosensor; ORR
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201802040

Microporous N,P‐codoped graphitic nanosheets (N,P‐CMP‐1000) were synthesized by thermal annealing (1000 °C) of as‐synthesized conjugated microporous polymers (CMPs) in the presence of phytic acid, which can be used as an effective metal‐free electrocatalyst for the oxygen reduction reaction (ORR) for energy conversion. In the whole pH range (i.e. alkaline, acidic, and neutral solutions), the obtained N,P‐CMP‐1000 exhibits superior electrocatalytic activity for ORR with a low overpotential, high current density, and good stability. Furthermore, N,P‐CMP‐1000 can also be applied for electrochemically sensing dissolved oxygen (DO), with a high sensitivity (1.89 μA mg−1 L) and broad detection range (2.56 to 16.65 mg L−1) due to its good electrocatalytic performance towards ORR in neutral solution. In vitro cytotoxicity tests (CCK‐8 and Live/Dead Cell Double Staining Assay) of N,P‐CMP‐1000 extracts demonstrated its good biocompatibility to Human Corneal Epithelial Cells (HCEC), which shows its great potential as an eye‐wearable biosensor for sensing DO in tears. Eye spy: Microporous N,P‐codoped carbon nanosheets were prepared by acid‐catalyzed condensation of commercially available 1,2,4,5‐benzenetetramine and hexaketocyclohexane, followed by carbonization in the presence of phytic acid, which were used as efficient metal‐free electrocatalysts for ORR over whole pH range (i.e., alkaline solution, acidic and neutral solutions), and eye‐wearable biosensors for sensing dissolved oxygen in tears or other body fluids.