Proton transport controlled at surface layer of CeO_(2) by gradient-doping with a built-in-field effect

Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different effects.The built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide materials.Herein,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk structure.The inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk-layer of CeO_(2)form the gradiently doped structure.The gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy levels.Moreover,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface layer.The acquired gradiently doped fluorite structure exhibits remarkable proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.

Fusion Energy and Stopping Power in a Degenerate DT Pellet Driven by a Laser-Accelerated Proton Beam

In this paper, we have improved the fast ignition scheme in order to have more authority needed for highenergy-gain. Due to the more penetrability and energy deposition of the particle beams in fusion targets, we employ a laser-to-ion converter foil as a scheme for generating energetic ion beams to ignite the fusion fuel. We find the favorable intensity and wavelength of incident laser by evaluating the laser-proton conversion gain. By calculating the source-target distance, proton beam power and energy are estimated. Our analysis is generalized to the plasma degeneracy effects which can increase the fusion gain several orders of magnitude by decreasing the ion-electron collisions in the plasma.It is found that the wavelength of 0.53 μm and the intensity of about 1020W/cm^2, by saving about 10% conversion coefficient, are the suitable measured values for converting a laser into protons. Besides, stopping power and fusion burn calculations have been done in degenerate and non-degenerate plasma mediums. The results indicate that in the presence of degeneracy, the rate of fusion enhances.