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Article Citation - WoS: 3Citation - Scopus: 3A Review on Membranes for Anion Exchange Membrane Water Electrolyzers(Pergamon-Elsevier Science Ltd, 2026) Altinisik, Hasan; Celebi, Ceren; Ozden, Adnan; Devrim, Yilser; Colpan, C. OzgurAnion exchange membrane water electrolyzers (AEMWEs) - using water and renewable electricity as the input - provide a sustainable pathway to hydrogen production. AEMWEs perform the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) with modest overpotentials at practical current densities (>1 A cm(-2)). The recent catalysis, component, and system-level breakthroughs have enabled significant improvements in current densities and energetic efficiencies. The challenge, however, is to maintain these impressive activities and efficiencies through long-term operation at scale. High-performance, efficient, stable, and economically viable AEMWEs require high-performance, low-cost, and scalable anion exchange membranes (AEMs). This Review provides an overview of physical, chemical, and transport properties of commercial and non-commercial AEMs. The article discusses the operating principles, structures, characteristics, strengths, and weaknesses of conventional and emerging AEMs, along with their performance and stability implications in AEMWEs. The article highlights the characteristics that have intricate implications on performance, stability, and cost. It discusses recent advances and best practices to combine high-performance, efficiency, stability, and low-cost in a single AEM structure. The Review highlights the trade-offs between AEM characteristics, with an overview of emerging approaches that would overcome performance, stability, and cost challenges. The Review concludes by highlighting the research gaps and providing research directions with the potential to take the technology a step closer to wide-scale deployment.Article First-Principles Investigation of Kaolinite/YSZ Heterostructure for Solar-Driven Photocatalytic Hydrogen Production(Pergamon-Elsevier Science Ltd, 2025) Park, Jongee; Yu, Eunmi; Fatima, Syeda AfrinishThis work employs density functional theory (DFT) to elucidate the structural, electronic, and photocatalytic properties of a kaolinite/yttria-stabilized zirconia (Kaol/YSZ) heterostructure tailored for solar-driven hydrogen generation. The lattice mismatch between Kaol(001) and YSZ(111) was determined to be 4.4 % along the a-axis and 2.2 % along the b-axis. Two interface terminations were modeled: an O-terminated Si-O surface and an OH-terminated Al-OH surface. The OH-terminated interface demonstrated a stronger interfacial binding energy (-9.32 eV per cell) and enhanced thermodynamic stability, indicating its suitability for photocatalytic water splitting. Electronic structure analysis reveals that the Kaol/YSZ heterostructure exhibits a narrowed band gap of 1.46 eV relative to the isolated components, which promotes enhanced visible-light absorption. A type-II band alignment is observed, facilitating photoinduced electron transfer from the conduction band of YSZ to the conduction band of Kaol and promoting efficient charge separation. Hirshfeld charge analysis confirms the existence of a built-in electric field at the interface that further drives charge migration. Calculated optical absorption spectra shows a red shift in the heterostructure's absorption edge, extending its photoresponse into the visible region. Under simulated solar irradiation, photogenerated electrons preferentially migrate to Kaol for proton reduction, while holes remain on the YSZ surface to oxidize water, enabling simultaneous H2 evolution and O2 evolution pathways. These findings highlight the promise of the Kaol/YSZ heterostructure as a robust visible-light photocatalyst for sustainable hydrogen production and environmental remediation.Article Citation - WoS: 7Citation - Scopus: 7Reliability and Optimal Age-Based Replacement Policy for Consecutive 2-Out System Equipped With Protection Blocks(Pergamon-Elsevier Science Ltd, 2025) Eryilmaz, SerkanThis paper concerns the reliability evaluation and optimal age-based replacement policy for the linear consecutive 2-out-of-n:G system whose two consecutive components are protected by a block that has its own failure rate. Two alternative methods are proposed to compute the reliability of the system. The first method is based on direct probabilistic approach and uses the reliability of the ordinary consecutive 2-outof-n:G system. The second method is based on the concept of survival signature. Closed form equations for the system reliability and the mean number of failed components within the system are obtained. The optimal age-based replacement policy is also defined and studied. Extensive numerical results are presented to illustrate the findings.