SENTEZ PARAMETRELERİNİN La1-xCaxMnyAl1-y (LCMA) KRİSTAL YAPISINA ETKİS

Yeşil enerji uygulamaları için hidrojen çok önemli bir yere sahiptir. Yenilenebilir enerji kaynaklarına dayalı hidrojen üretimi bu bağlamda kritik bir role sahiptir. Güneş enerjisine dayalı termokimyasal yöntemler, sürdürülebilir bir şekilde hidrojen üretimi için dikkat çekmektedir. İki aşamalı termokimyasal su ayırma (TSA) yöntemi ile saflaştırmaya gerek kalmadan hidrojen üretmek mümkündür. Redoks reaksiyonlarının termodinamiği ve kinetiği, hidrojen üretim verimini belirleyen önemli faktörlerden biridir ve yapısal kararlılık TSA redoks reaksiyonları için çok önemlidir. Hidrojen üretim verimliliği, redoks reaksiyonlarda kullanılan aktif malzemelerin yapısal özelliklerinden önemli bir şekilde etkilenmektedir. Bu bakımdan perovskit oksitler, kompozisyon çeşitliliği ile birlikte üstün yapısal kararlılıkları nedeniyle TWS reaksiyonlarında kullanılabilen aktif bir malzeme olarak dikkat çekmektedir. Bu çalışmada sentez parametrelerinin TWS ile yüksek hidrojen üretebilme kapasitesine sahip olan La0.4Ca0.6Mn0.6Al0.4O3 (LCMA4664) ve La0.2Ca0.8Mn0.8Al0.2O3 (LCMA2882) perovskit tipi oksitlerin yapısal özellikleri üzerine etkisinin araştırılması amaçlanmıştır. LCMA oksit ailesindeki farklı stokiyometrinin sentez parametreleri ile birlikte ortaya çıkan kristal yapı üzerinde etkisi olduğu bulunmuştur.

EFFECT of SYNTHESIS PARAMETERS on the CRYSTAL STRUCTURE of La1-xCaxMnyAl1-y (LCMA)

Hydrogen is an essential substance for green-energy applications. The production of hydrogen-based on renewableenergy sources has a critical role in this context. Thermochemical methods based on solar energy are getting attention forhydrogen production in a sustainable manner. It is possible to produce hydrogen without the need of purification via twostep thermochemical water splitting (TWS) method. The thermodynamics and kinetics of redox reactions in activematerials used are the important factors for determining the hydrogen production efficiency. The structural stability isanother concern in the TWS reactions. The efficiency is strongly influenced by the structural properties of active materialsused in these reactions. In this regard, perovskite-oxides draw attention as an active material that can be used in TWSreactions due to their superior structural stability together with their compositional diversity. In this study, it was aimedto investigate the effect of synthesis parameters on the structural properties of La0.4Ca0.6Mn0.6Al0.4O3 (LCMA4664) andLa0.2Ca0.8Mn0.8Al0.2O3 (LCMA2882) perovskite-type oxides that offer high hydrogen production efficiency by TWS. It wasfound that different stoichiometry in LCMA oxide family has an effect on the resulting crystal structure together with thesynthesis parameters.

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Mugla Journal of Science and Technology-Cover

ISSN: 2149-3596
Yayın Aralığı: Yılda 2 Sayı
Başlangıç: 2015
Yayıncı: Muğla Sıtkı Koçman Üniversitesi Fen Bilimleri Enstitüsü

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