| 1. |
- Liu, Qinghua, et al.
(författare)
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Advanced electrolyte-free fuel cells based on functional nanocomposites of a single porous component : analysis, modeling and validation
- 2012
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Ingår i: RSC Advances. - : Royal Society of Chemistry (RSC). - 2046-2069. ; 2:21, s. 8036-8040
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Tidskriftsartikel (refereegranskat)abstract
- Recently, a fuel cell device constructed with only one layer composited of ceria-based nanocomposites (typically, lithium nickel oxide and gadolinium doped ceria (LiNiO2-GDC) composite materials), called an electrolyte-free fuel cell (EFFC), was realized for energy conversion by Zhu et al. The maxium power density of this single-component fuel cell is 450 mW cm(-2) at 550 degrees C when using hydrogen fuel. In this study, a model was developed to evaluate the performance of an EFFC. The kinetics of anodic and cathodic reactions were modeled based on electrochemical impedance spectroscopy (EIS) measurements. The results show that both of the anodic and cathodic reactions are kinetically fast processes at 500 degrees C. Safety issues of an EFFC using oxidant and fuels at the same time without a gas-tight separator were analyzed under open circuit and normal operation states, respectively. The reaction depth of anodic and cathodic processes dominated the competition between surface electrochemical and gas-phase reactions which were effected by the catalytic activity and porosity of the materials. The voltage and power output of an EFFC were calculated based on the model and compared with the experimental results.
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| 2. |
- Zhu, Bin, 1956-, et al.
(författare)
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A new energy conversion technology joining electrochemical and physical principles
- 2012
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Ingår i: RSC Advances. - 2046-2069. ; 2:12, s. 5066-5070
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Tidskriftsartikel (refereegranskat)abstract
- We report a new energy conversion technology joining electrochemical and physical principles. This technology can realize the fuel cell function but built on a different scientific principle. The device consists of a single component which is a homogenous mixture of ceria composite with semiconducting materials, e.g. LiNiCuZn-based oxides. The test devices with hydrogen and air operation delivered a power density of 760mWcm(-2) at 550 degrees C. The device has demonstrated a multi-fuel flexibility and direct alcohol and biogas operations have delivered 300-500 mW cm(-2) at the same temperature. Device physics reveal a key principle similar to solar cells realizing the function based on an effective separation of electronic and ionic conductions and phases within the single-component. The component material multi-functionalities: ion and semi-conductions and bi-catalysis to H-2 or alcohol (methanol and ethanol) and air (O-2) enable this device realized as a fuel cell.
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| 3. |
- Zhu, Bin, et al.
(författare)
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A single-component fuel cell reactor
- 2011
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Ingår i: International journal of hydrogen energy. - : Elsevier BV. - 0360-3199 .- 1879-3487. ; 36:14, s. 8536-8541
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Tidskriftsartikel (refereegranskat)abstract
- We report here a single-component reactor consisting of a mixed ionic and semi-conducting material exhibiting hydrogen-air (oxygen) fuel cell reactions. The new single-component device was compared to a conventional three-component (anode/electrolyte/cathode) fuel cell showing at least as good performance. A maximum power density of 300-600 mW cm(-2) was obtained with a LiNiZn-oxide and ceria-carbonate nanocomposite material mixture at 450-550 degrees C. Adding a redox catalyst element (Fe) resulted in an improvement reaching 700 mW cm(-2) at 550 degrees C.
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| 4. |
- Zhu, Bin, et al.
(författare)
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Fuel cells based on electrolyte and non-electrolyte separators
- 2011
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Ingår i: Energy & Environmental Science. - : Royal Society of Chemistry (RSC). - 1754-5692 .- 1754-5706. ; 4:8, s. 2986-2992
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Tidskriftsartikel (refereegranskat)abstract
- In the long-history of fuel cell R&D, the electrolyte is an essential part in a three-component configuration because it separates the anode and cathode to realize the fuel cell's functions. We report here non-electrolyte separator fuel cells (NEFCs) compared with electrolyte based fuel cells (EBFCs). The NEFC consists of single- or dual-components based on mixed ionic and semi-conductors but with no electrolyte separator. A maximum power density of 680 mW cm(-2) has been achieved by the NEFC at 550 degrees C. The NEFCs exhibit performances comparable to, and in some cases even better than, those of conventional EBFCs. The design of NEFCs, new material functionalities and device performances may contribute to new fuel cell R&D.
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