A solar-powered microbial electrolysis cell with a platinum catalyst-free cathode to produce hydrogen.
ABSTRACT This paper reports successful hydrogen evolution using a dye-sensitized solar cell (DSSC)-powered microbial electrolysis cell (MEC) without a Pt catalyst on the cathode, indicating a solution for the inherent drawbacks of conventional MECs, such as the need for an external bias and catalyst. DSSCs fabricated by assembling a ruthenium dye-loaded TiO(2) film and platinized FTO glass with an I(-)/I(3)(-) redox couple were demonstrated as an alternative bias (V(oc) = 0.65 V). Pt-loaded (0.3 mg Pt/cm(2)) electrodes with a Pt/C nanopowder showed relatively faster hydrogen production than the Pt-free electrodes, particularly at lower voltages. However, once the applied photovoltage exceeded a certain level (0.7 V), platinum did not have any additional effect on hydrogen evolution in the solar-powered MECs: hydrogen conversion efficiency was almost comparable for either the plain (71.3-77.0%) or Pt-loaded carbon felt (79.3-82.0%) at >0.7 V. In particular, the carbon nanopowder-coated electrode without Pt showed significantly enhanced performance compared to the plain electrode, which indicates efficient electrohydrogenesis, even without Pt by enhancing the surface area. As the applied photovoltage was increased, anodic methanogenesis decreased gradually, resulting in increasing hydrogen yield.
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ABSTRACT: Development of visible light responsive photocatalysts is a promising research area to facilitate utilization of solar energy for hydrogen production via photocatalytic water splitting. In this study two groups of samples, nitrogen (N)-doped niobium pentoxide () and titanium dioxide () (, , ) and N-undoped ones ( and ) were tested. In order to utilize visible light, nitrogen atoms were doped in selected photocatalysts by using urea. A shift of the absorption edges of the Ndoped samples in the visible light region was observed. Under visible light irradiation, N-doped samples were more prominent photocatalytic activities than the N-undoped samples. Specifically, 99.7% of rhodamine B (RhB) was degraded after 60 minutes of visible light irradiation with . Since shows the highest activity of RhB degradation, it was supposed to generate the highest current response. However, showed the highest current response () than . More interestingly, when we compare the hydrogen production, produced of hydrogen.01/2011; 33(12).
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ABSTRACT: Breaking through the “fermentation barrier” bottleneck of conventional biological hydrogen production technology, achieving the depth use of carbon source, and obtaining the higher hydrogen production, bioelectrocatalysis technology assisted fermentation process has vast prospective of applications. The main technical route is the microbial electrolysis cell (MEC). Based on the cutting-edge researches carried out by worldwide scholars, this paper focuses on the comprehensive discussion of MEC design, substrate selection, electrode materials, performance optimization, microbiology, as well as the main problems of the corresponding research. The review also presents recommendations and solutions accordingly. Finally, the prospects of microbial electrocatalysis assisted technology in the field of environmental pollution control and energy recovery application have been disclosed.Desalination and water treatment 08/2014; 52(28-30). DOI:10.1080/19443994.2013.808583 · 0.99 Impact Factor
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ABSTRACT: Bioelectrochemical systems (BES) and forward osmosis (FO) are two emerging technologies with great potential for energy-efficient water/wastewater treatment. BES takes advantage of microbial interaction with a solid electron acceptor/donor to accomplish bioenergy recovery from organic compounds, and FO can extract high-quality water driven by an osmotic pressure. The strong synergy between those two technologies may complement each other and collaboratively address water-energy nexus. FO can assist BES with achieving water recovery (for future reuse), enhancing electricity generation, and supplying energy for accomplishing the cathode reactions; while BES may help FO with degrading organic contaminants, providing sustainable draw solute, and stabilizing water flux. This work has reviewed the recent development that focuses on the synergy between BES and FO, analyzed the advantages of each combination, and provided perspectives for future research. The findings encourage further investigation and development for efficient coordination between BES and FO towards an integrated system for wastewater treatment and reuse.Water 12/2014; 7(1)(1):38-50. DOI:10.3390/w7010038 · 1.29 Impact Factor