Publications de Arata Nakajo | EPFL Graph Search

Prediction of crack nucleation and propagation in porous ceramics using the phase-field approach

The relevance of the phase-field approach to simulate the fracture in porous ceramics has been investigated. For this purpose, the conditions for the crack initiation using the phase-field model have been compared to the theoretical predictions of the coup ...

ELSEVIER2022

Fracture properties of porous yttria-stabilized zirconia under micro-compression testing

Arata Nakajo

Micro-compression tests were carried out on pillars of 60 mu m in diameter, milled by plasma focused ion beam in porous Yttria-Stabilized Zirconia (YSZ) pellets. The fracture properties were determined over a wide range of porosities (33 %-63 %) for 8YSZ a ...

ELSEVIER SCI LTD2022

Techno-Economic Optimization of an Integrated Biomass Waste Gasifier–Solid Oxide Fuel Cell Plant

François Maréchal, Jan Van Herle, Jürg Alexander Schiffmann, Victoria Xu Hong He, Arata Nakajo, Maria del Mar Perez Fortes

With a growing energy demand in a carbon-constrained society, fuels cells powered by renewable fuels, and specifically solid waste, are seen as interesting contributors to the energy portfolio. The alternative energy industry needs to reduce costs, enhance ...

2021

Evolution of the Morphology Near Triple-Phase Boundaries in Ni–Yttria Stabilized Zirconia Electrodes Upon Cathodic Polarization

Jan Van Herle, Marco Cantoni, Guillaume Jeanmonod, Lucie Navratilova, Arata Nakajo, Priscilla Caliandro, Giorgio Rinaldi

Microstructural changes in Ni–yttria stabilized zirconia (YSZ) near the YSZ electrolyte were examined by three-dimensional (3D) electron microscopy after electrolysis and fuel cell operation up to 10,700 h and 15,000 h, respectively. The depletion of Ni an ...

2020

Emerging Investigators in Electrochemical Energy Conversion and Storage 2020

Arata Nakajo

ASME2020

Effects of Polarization on the Microstructural Changes at the YSZ/Ni-YSZ Interface

Jan Van Herle, Lucie Navratilova, Arata Nakajo, Priscilla Caliandro, Giorgio Rinaldi

This study examines the effect of Ni migration near the interface with the electrolyte after fuel cell (SOFC) and electrolysis mode (SOEC) operation on nickel-yttria stabilized zirconia (Ni-YSZ) electrodes. The experimental dataset consists in a series of ...

2019

Model-assisted identification of solid oxide cell elementary processes by electrochemical impedance spectroscopy measurements

Jan Van Herle, Stefan Diethelm, Arata Nakajo, Priscilla Caliandro

Electrochemical Impedance Spectroscopy (EIS) is extensively used to characterize Solid Oxide Cells (SOCs) to extract information on the elementary loss mechanisms. However, these individual mechanisms usually overlap in the frequency domain, requiring dedi ...

2019

Characterization of local morphology and availability of triple-phase boundaries in solid oxide cell electrodes

Jan Van Herle, Marco Cantoni, Arata Nakajo, Pierre Burdet, Giorgio Rinaldi

The performance of solid oxide cells is known to be dependent upon the density of three phase boundaries (TPB), but the potential for improving their effective electrocatalytic activity by morphological adjustments is imprecisely known. A spilling algorith ...

2019

Analytical transport network theory to guide the design of 3-D microstructural networks in energy materials: Part 1. Flow without reactions

Arata Nakajo

We present a fully analytical, heuristic model the "Analytical Transport Network Model" for steady-state, diffusive, potential flow through a 3-D network. Employing a combination of graph theory, linear algebra, and geometry, the model explicitly relates a ...

Elsevier Science Bv2017

Production and Reliability Oriented SOFC Cell and Stack Design

Jan Van Herle, Arata Nakajo, Zacharie Wuillemin, Fabio Greco, Xin Wang

This paper presents an innovative development methodology for a production and reliability oriented SOFC cell and stack design aiming at improving the stacks robustness, manufacturability, efficiency and cost. Multi-physics models allowed a probabilistic a ...

2017