Bioelectricity Generation in Batch-Fed Up-Flow Membrane-Less Microbial Fuel Cell: Effect of Surface Morphology of Carbon Materials as Aqeuous Biocathodes Wei-Eng Thung & Soon-An Ong & Li-Ngee Ho & Yee-Shian Wong & Fahmi Ridwan & Yoong-Ling Oon & Yoong-Sin Oon & Harvinder Kaur Lehl Received: 16 April 2016 /Accepted: 28 June 2016 # Springer International Publishing Switzerland 2016 Abstract The surface morphology of biocathode was one of the limiting factors for microbial fuel cell (MFC) design. Up-flow membrane-less single-chambered MFC (UFML MFC) was used to investigate the effect of surface morphology of carbon material as aqueous biocathode. Pt-loaded carbon paper, carbon felt, and carbon plate were examined and compared on the power output, surface morphology for biofilm formation, Cou- lombic efficiency (CE), and chemical oxygen demand (COD) reduction. The COD reduction was up to 90 % in UFML MFC with Pt-loaded carbon paper, carbon felt, and carbon plate as aqueous biocathodes. The results obtained showed that the performance in voltage output was not related to internal resistance but mainly due to the ability of cathode material in oxygen reduction process. The performance of voltage output with differ- ent materials as aqueous biocathode was mainly based on to the surface morphology as it was related to the ability of biofilm formation. Roughness of aqueous biocathode’ s surface morphology could prompt the bio- film growth, while biofilm overgrowth on aqueous biocathode could decrease voltage output. Therefore, smoother surface morphology of aqueous biocathode is more suitable for long-term operation. Keywords MFC . Up-flow . Membrane less . Aqueous biocathode . Carbon material . Surface morphology 1 Introduction Fossil fuel, especially petroleum, is one of the sources emitting carbon dioxide into the atmosphere. The in- creasing demand and applications of fossil fuel acceler- ate its depletion rate, subsequently increasing the amount of carbon dioxide in the atmosphere; these are the phenomena of global crisis, for energy source and the environment. Microbial fuel cell (MFC) is a sustain- able technology in which microorganism is used to oxidize organic carbon sources while generating electri- cal energy at the same time. The mechanism of MFC includes the generation of electrons and protons via the breakdown of organic matter by anaerobic microbes surrounding the anode electrode (Rabaey and Verstraete 2005). The electrons are transferred through the external circuit from anode electrode to cathode electrode for current generation (Logan et al. 2005). The power output of MFC is still inadequate to be practiced in real application, as its performance may be affected by design of MFC including material, spacing distance, size and specific surface area of the electrode; availability of separator; and the availability of the cat- alyst at cathode region (Gil et al. 2003; Rabaey and Verstraete 2005; Venkata Mohan et al. 2014). Water Air Soil Pollut (2016) 227:254 DOI 10.1007/s11270-016-2961-5 W.<E. Thung : S.<A. Ong (*) : Y.<S. Wong : F. Ridwan : Y.<L. Oon : Y.<S. Oon : H. K. Lehl Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia e-mail: ongsoonan@yahoo.com L.<N. Ho School of Materials Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia