A new strategy for designing high-performance sulfonated poly(ether ether ketone) polymer electrolyte membranes using inorganic proton conductor-functionalized carbon nanotubes

Chunli Gong, Xuan Zheng, Hai Liu, Guangjin Wang, Fan Cheng, Genwen Zheng, Sheng Wen, Wing Cheung Law, Chi Pong Tsui, Chak Yin Tang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

88 Citations (Scopus)


Remarkable progress has been made on the use of polymer electrolyte membranes (PEMs) for renewable-energy-related research. In particular, carbon nanotubes (CNTs) have emerged as versatile nanomaterials to modify PEMs. However, the inert ionic conduction ability and possible short-circuiting risk are the two major obstacles to their further development. In this work, CNTs are firstly functionalized with an inorganic proton conductor, boron phosphate (BPO4), using a facile polydopamine-assisted sol-gel method to yield BPO4@CNTs. This new additive is then used to modify sulfonated poly(ether ether ketone) (SPEEK). Polydopamine coating layer can act as an extraordinary glue to homogeneously adhere BPO4nanoparticles on CNTs, thereby not only reducing the risk of short-circuiting, but also fabricating new proton-conducting pathways in the composite membranes. A comprehensive characterization reveals that the thermal stability, tensile properties, and dimensional stability of PEMs are significantly improved. Compared with pure SPEEK, the proton conductivity of SPEEK/BPO4@CNTs-2 is improved by 45% and 150% at 20 °C and at 80 °C, respectively. Furthermore, the H2/O2cell performance of SPEEK/BPO4@CNTs-2 membrane exhibits a peak power density of 340.7 mW cm-2at 70 °C, which is significantly better than that of pure SPEEK (254.2 mW cm-2), demonstrating the great potential of proton conductors-functionalized CNTs in PEMs.
Original languageEnglish
Pages (from-to)453-464
Number of pages12
JournalJournal of Power Sources
Publication statusPublished - 1 Sep 2016


  • Boron phosphate
  • Carbon nanotubes
  • Fuel cells
  • Proton exchange membrane
  • Sulfonated poly(ether ether ketone)

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Energy Engineering and Power Technology
  • Physical and Theoretical Chemistry
  • Electrical and Electronic Engineering

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