title: Novel CuCo2O4/graphitic carbon nitride nanohybrids: Highly effective catalysts for reducing CO generation and fire hazards of thermoplastic polyurethane nanocomposites.
abstract: Novel spinel copper cobaltate (CuCo2O4)/graphitic carbon nitride (g-C3N4) (named C-CuCo2O4) nanohybrids with different weight ratios of g-C3N4 to CuCo2O4 were successfully synthesized via a facile hydrothermal method. Then the nanohybrids were added into the thermoplastic polyurethane (TPU) matrix to prepare TPU nanocomposites using a master batch-melt compounding approach. Morphological analysis indicated that CuCo2O4 nanoparticles were uniformly distributed on g-C3N4 nanosheets. Thermal analysis revealed that C-CuCo2O4-7 (proportion of g-C3N4 to CuCo2O4 of 93/7) was an optimal nanohybrid for the properties improvement of TPU. Incorporation of C-CuCo2O4-7 into TPU led to significant improvements in the onset decomposition temperature, temperature at maximal mass loss rate and char yields. The heat release rate and total heat release of TPU/C-CuCo2O4-7 decreased by 37% and 31.3%, respectively, compared with those of pure TPU. Furthermore, the amounts of pyrolysis gaseous products, including combustible volatiles and carbon monoxide (CO), were remarkably reduced, whereas, non-flammable gas (carbon dioxide) increased. Excellent dispersion of C-CuCo2O4-7 in TPU host was achieved, due to the synergistic effect between g-C3N4 and CuCo2O4. Enhancements in the thermal stability and flame retardancy were attributed to the explanations that g-C3N4 nanosheets showed the physical barrier effect and catalytic nitrogen monoxide (NO) decomposition, and that CuCo2O4 catalyzes the reaction of CO with NO and increased char residues.
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China; USTC-CityU Joint Advanced Research Center, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren'ai Road, Suzhou, Jiangsu 215123, PR China.
authors.forename: Yongqian
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China; USTC-CityU Joint Advanced Research Center, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren'ai Road, Suzhou, Jiangsu 215123, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China.
authors.forename: Keqing
authors.initials: K
authors.lastname: Zhou
authors.affiliation: USTC-CityU Joint Advanced Research Center, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren'ai Road, Suzhou, Jiangsu 215123, PR China; Department of Architecture and Civil Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
authors.forename: Richard K K
authors.initials: RK
authors.lastname: Yuen
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China. Electronic address: zgui@ustc.edu.cn.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Gui
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China; USTC-CityU Joint Advanced Research Center, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren'ai Road, Suzhou, Jiangsu 215123, PR China. Electronic address: yuanhu@ustc.edu.cn.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510641, PR China.
authors.forename: Saihua
authors.initials: S
authors.lastname: Jiang
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D005390:Fires; D006108:Graphite / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry*; D009570:Nitriles / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*
chemical_list: D009570:Nitriles; D011140:Polyurethanes; D003035:Cobalt; C011206:cyanogen; D006108:Graphite; D003300:Copper; D002248:Carbon Monoxide
keywords: CO reduction; Catalysis; Copper cobaltate; Fire hazards; Graphitic carbon nitride