Self-ignition combustion synthesis of TiFe1−xMnx hydrogen storage alloy

Abstract

(147 words)The paper describes the self-ignition combustion synthesis (SICS) of the hydrogen storage alloy TiFe 1-X Mn X (X = 0, 0.1, 0.2, 0.3, and 0.5) in a hydrogen atmosphere, where the hydrogenation properties of the products are mainly examined. In the experiments, the well-mixed powders of Ti, Fe, and Mn in the molar ratio of 1:1-X:X were uniformly heated up to 1473 K, and then were cooled naturally in pressurized hydrogen at 0.9 MPa. All products were successfully synthesized by utilizing the exothermic reaction, which occurred at around 1358 K. The XRD analysis showed that SICS generated TiFe 1-X Mn X in the range of X value from 0 to 0.3. All SICSed products absorbed hydrogen smoothly at 298 K at an initial pressure of 4.1 MPa. Most significantly, TiFe 0.8 Mn 0.2 improved the dual plateau property. The results revealed that SICS was quite effective for producing the hydrogen storage alloy TiFe 1-X Mn X .Self-ignition Combustion Synthesis of TiFe 1-X Mn X Hydrogen Storage Alloy 3

Substitutional effects in TiFe for hydrogen storage: a comprehensive review

“…Furthermore the hysteresis between absorption and desorption is reduced. [52] The good kinetics seems not to be related to hydride stability nor to particle size, but to the formation of Mn clusters that enhances a faster hydrogenation compared to TiFe. [184] Sandrock et al reported the thermodynamics of TiFe0.85Mn0.…”

“…As an alternative to melting, TiFe can also be obtained and processed by Severe Plastic Deformation (SPD) techniques, such as ball milling [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45] and high pressure torsion [46][47][48][49][50], as well as by self-ignition. [51][52][53]. SPD techniques lead to fresh and defective surfaces, that help alloy activation and also nanostructuration, but reducing nominal capacity.…”

Combustion synthesis of TiFe by utilizing magnesiothermic reduction

“…Generally, TiFe acquires sufficient ability to store hydrogen at ordinary temperatures after the repeating procedures of hydrogenation and dehydrogenation more than 10 times. Many researches concerned with improving the initial activation of TiFe have been reported, among which doping TiFe with a third element such as Mn, V, O, or Ti is a considerably popular method [8][9][10][11][12]. However, there have been few researches focusing on finding new production methods for TiFe.…”

“…TiFe synthesized by this method stored hydrogen as much as 1.7 mass%, which is about 95% of the theoretical capacity. Wakabayashi and Yasuda et al reported the production of TiFe, TiFe 1Àx Mn x , and oxygen-doped TiFe by using the SICS method [9,10,17]. In their methods, mixed powders with desired compositions were uniformly heated up in a pressurized hydrogen atmosphere to directly synthesize TiFe alloys.…”

Self-ignition combustion synthesis of LaNi5 utilizing hydrogenation heat of metallic calcium

“…Most recently, Wakabayashi et al [6][7][8] reported the use of self-ignition combustion synthesis (SICS) to produce TiFe-based alloys; in this method, powders mixed in a desired molar ratio were uniformly heated up to the ignition point in pressurized hydrogen atmosphere. The product was also directly synthesized with the help of the exothermic reaction of titanium hydrogenation.…”