Mechanical and electronic properties of CeO2 under uniaxial tensile loading: A DFT study

First-principles high-throughput screening of bulk piezo-photocatalytic materials for sunlight-driven hydrogen production

“…Uniaxially strained bulk geometry relaxations were performed with a conjugate-gradient algorithm that allowed for volume variations while imposing the structural constraints defining uniaxial strain. 12 In our simulations, uniaxial strain is defined as η = ( c − c 0 )/ c 0 , where c 0 represents the length of the strained lattice vector in the absence of any stress. Positive η values are considered tensile uniaxial strains and η < 0 compressive.…”

“…10 Recently, some of us have shown by means of rst-principles calculations that mechanical strains (biaxial and uniaxial) can modify the band-gap properties of transition-metal oxides in a signicant and consistent manner. 11,12 In practice, biaxial strains of 1-5% can be introduced in crystals by growing thin lms on top of substrates that present a lattice mismatch. 13,14 Similarly, uniaxial strains of comparable sizes can be realized in microstructured materials via mechanical actuation 15,16 and/or exposure to ultrasound waves.…”

High-throughput screening of piezo-photocatalytic materials for hydrogen production

“…For integrations within the Brillouin zone (BZ) of all materials we employed Monkhorst-Pack k-point grids [43] of spacing 2π × 0.01 Å−1 . Uniaxially strained bulk geometry relaxations were performed with a conjugate-gradient algorithm that allowed for volume variations while imposing the structural constraints defining uniaxial strain [12]. In our simulations, uniaxial strain is defined as η = (c − c 0 ) /c 0 , where c 0 represents the length of the strained lattice vector in the absence of any stress.…”

“…Recently, some of us have shown by means of firstprinciples calculations that mechanical strains (biaxial and uniaxial) can modify the band-gap properties of transition-metal oxides in a significant and consistent manner [11,12]. In practice, biaxial strains of 1-5% can be introduced in crystals by growing thin films on top of substrates that present a lattice mismatch [13,14].…”

Experimental Investigation on Potential Effect of Cell Shape and Size on the Residual Stress in Solid Oxide Fuel Cells

“…Residual stresses are developed during the manufacturing process of the cells due to the thermo-elastic mismatch between the cell layers (Selçuk et al, 2001;He et al, 2011;Molla et al, 2013;Wei et al, 2018;Shang et al, 2019;Frandsen et al, 2021). These residual stresses can result in performance degradation (Li et al, 2020;Liu et al, 2021) as a result of delamination (Selçuk et al, 2001) or the formation of cracks in the cell layers (Selçuk et al, 2001;Ettler et al, 2010;Li et al, 2010) and in the extreme case may lead to the complete deterioration of the cell Zhang et al, 2008;Villanova et al, 2010).…”