one of the most important fuel cells (fcs) is proton exchange membrane fuel cells (pemfcs). the outputvoltage of this fc depends on current loads. this paper tries to introduce, implement and control the voltage ofpemfc, during load variations. the output voltage of fuel cell should be constant during load variation. toachieve this goal, a controller should be designed. here, the lead-lag contr...

For the goal of practical industrial development of fuel cells, cheap, sustainable and high performance electrocatalysts for oxygen reduction reactions (ORR) which rival those based on platinum (Pt) and other rare materials are highly desirable. In this work, we report a class of cheap and high-performance metal-free oxygen reduction electrocatalysts obtained by co-doping carbon blacks with nit...

Effects of cathode types on the long-term stability of microbial fuel cell (MFC) and the anodic microbial communities were studied using K(3)Fe(CN)(6) catholyte (R1), air cathode (R2) and biocathode (R3) over a testing time of 400 d. Upon 400 d of testing, the maximum power densities (P(max)) of R1 and R2 decreased by 44% and 37%, and the Coulombic efficiencies (CEs) decreased 8.4% (R1) and 2.0...

For the development of long lasting portable microbial fuel cells (MFCs) new strategies are necessary to overcome critical issues such as hydraulic pump system and the biochemical substrate retrieval overtime to sustain bacteria metabolism. The present work proposes the use of a synthetic solid anolyte (SSA), constituted by agar, carbonaceous and nitrogen sources dissolved into diluted seawater...

This study investigates the effect of 1 mmol dm(-3) concentrations of a selection of small cationic molecules on the performance of a fuel cell grade oxygen reduction reaction (ORR) catalyst (Johnson Matthey HiSPEC 3000, 20 mass% Pt/C) in aqueous KOH (1 mol dm(-3)). The cationic molecules studied include quaternary ammonium (including those based on bicyclic systems) and imidazolium types as we...

In the work presented here, nitrogen and sulfur co doped on porous graphene was synthesized using pyrolysis at 900°C for 2h and the hydrothermal technique at 180°C for 24h as metal-free electrocatalysts for oxygen reduction reaction (ORR) under alkaline conditions. All the materials have been characterized by Scanning Electron Microscopy (SEM) and X-ray photo-electron spectroscopy (XPS). Moreov...

Aromatic polyelectrolytes via polyacylation of pre-quarternized monomers for alkaline fuel cells Zhenghui Zhang, Liang Wu, John Varcoe, Chuanrun Li, Ai Lien Ong, Simon Poynton and Tongwen Xu* a CAS Key Laboratory of Soft Matter Chemistry, School of Chemistry and Material Science, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China. Fax: (+86) 0551-3601592; Tel: (+86...

A one-pot solvothermal process has been developed for direct preparation of PdCu nanocapsules (with a size of ca. 10 nm) on three-dimensional (3D) graphene. Due to the 3D pore-rich network of graphene and the unique hollow structure of PdCu nanocapsules with a wall thickness of ca. 3 nm, the newly-prepared PdCu/3D graphene hybrids activated electrochemically have great electrocatalytic activity...