Surface bound nanostructures of ternary r-GO / Mn3O4/V2O5 system for room temperature selectivity of hydrogen gas

A new materials testing apparatus using an external loading system in 230 MPa hydrogen at room temperature was developed. The apparatus consisted of a pressure vessel with a loading device for the slow strain rate technique (SSRT). The elimination of the axial load due to high pressure acting on the pull rod was achieved by the pressure balance method. The apparatus was designed to measure the actual load on the specimen with an external load cell irrespective of the axial load caused by high pressure and friction at the sliding seals. The hydrogen gas embrittlement (HGE) of austenitic stainless steels, SUS304, SUS316, SUS316LN, SUS316L and SUS310S of the Japanese Industrial Standard (JIS), and an iron-based superalloy, SUH660 JIS, and a nickel-based superalloy, Hastelloy C22, was evaluated by conducting SSRT tests in 210 MPa hydrogen using the apparatus at room temperature. The following was observed: SUS304, moderate HGE in stage II; SUS316, moderate HGE in stage III; SUS316LN, light HGE in stage III; SUS316L, light HGE in FS; SUS310S, undetectable HGE; SUH660, light HGE in stage III; and Hastelloy C22, heavy HGE in stage II. The HGE of the materials was also discussed.

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Room-Temperature Hydrogen-Gas Sensor Based on Carbon Nanotube Yarn

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17607 ◽

2020 ◽

Vol 20 (7) ◽

pp. 4011-4014 ◽

Cited By ~ 1

Author(s):

Maeum Han ◽

Jae Keon Kim ◽

Junyeop Lee ◽

Hee Kyung An ◽

Jong Pil Yun ◽

...

Keyword(s):

Carbon Nanotube ◽

Gas Sensor ◽

Room Temperature ◽

Hydrogen Gas ◽

Step Procedure ◽

One Step ◽

Cnt Arrays ◽

Removal Of Impurities ◽

Yarn Surface ◽

Higher Sensitivity

The proposed study describes the development of a carbon nanotube (CNT)-based gas sensor capable of detecting the presence of hydrogen (H2) gas at room temperature. CNT yarn used in the proposed sensor was fabricated from synthesized CNT arrays. Subsequently, the yarn was treated by means of a simple one-step procedure, called acid treatment, to facilitate removal of impurities from the yarn surface and forming functional species. To verify the proposed sensor’s effectiveness with regard to detection of H2 gas at room temperature, acid-treated CNT and pure yarns were fabricated and tested under identical conditions. Corresponding results demonstrate that compared to the untreated CNT yarn, the acid-treated CNT yarn exhibits higher sensitivity to the presence of H2 gas at room temperature. Additionally, the acid-treated CNT yarn was observed to demonstrate excellent selectivity pertaining to H2 gas.

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A Room-temperature Hydrogen Gas Sensor Using Palladium-decorated Single-Walled Carbon Nanotube/Si Heterojunction

Materials Science ◽

10.5755/j01.ms.22.2.12925 ◽

2016 ◽

Vol 22 (2) ◽

Cited By ~ 1

Author(s):

Yong Gang DU ◽

Hai Xia ZHENG ◽

Hao NI

Keyword(s):

Carbon Nanotube ◽

Gas Sensor ◽

Room Temperature ◽

Hydrogen Gas ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon

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Effect of High Pressure Gaseous Hydrogen on Fatigue Properties of SUS304 and SUS316 Austenitic Stainless Steel

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2018-84267 ◽

2018 ◽

Author(s):

Takashi Iijima ◽

Hirotoshi Enoki ◽

Junichiro Yamabe ◽

Bai An

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Fatigue Life ◽

Austenitic Stainless Steel ◽

Room Temperature ◽

Hydrogen Gas ◽

Gaseous Hydrogen ◽

Life Test ◽

Air Atmosphere ◽

Fatigue Life Test

A high pressure material testing system (max. pressure: 140 MPa, temperature range: −80 ∼ 90 °C) was developed to investigate the testing method of material compatibility for high pressure gaseous hydrogen. In this study, SSRT and fatigue life test of JIS SUS304 and SUS316 austenitic stainless steel were performed in high pressure gaseous hydrogen at room temperature, −45, and −80 °C. These testing results were compared with those in laboratory air atmosphere at the same test temperature range. The SSRT tests were performed at a strain rate of 5 × 10−5 s−1 in 105 MPa hydrogen gas, and nominal stress-strain curves were obtained. The 0.2% offset yield strength (Ys) did not show remarkable difference between in hydrogen gas and in laboratory air atmosphere for SUS304 and SUS316. Total elongation after fracture (El) in hydrogen gas at −45 and −80 °C were approximately 15 % for SUS304 and 20% for SUS316. In the case of fatigue life tests, a smooth surface round bar test specimen with a diameter of 7 mm was used at a frequency of 1, 0.1, and 0.01 Hz under stress rate of R = −1 (tension-compression) in 100 MPa hydrogen gas. It can be seen that the fatigue life test results of SUS304 and SUS316 showed same tendency. The fatigue limit at room temperature in 100 MPa hydrogen gas was comparable with that in laboratory air. The room temperature fatigue life in high pressure hydrogen gas appeared to be the more severe condition compared to the fatigue life at low temperature. The normalized stress amplitude (σa / Ts) at the fatigue limit was 0.37 to 0.39 for SUS304 and SUS316 austenitic stainless steels, respectively.

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Progress of hydrogen gas generation by reaction between iron and steel powder and carbonate water in the temperature range near room temperature

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.03.087 ◽

2020 ◽

Vol 45 (27) ◽

pp. 13832-13840

Author(s):

Hiromi Eba ◽

Masashi Takahashi ◽

Kenji Sakurai

Keyword(s):

Room Temperature ◽

Steel Powder ◽

Hydrogen Gas ◽

Gas Generation ◽

Carbonate Water ◽

Iron And Steel ◽

Temperature Range

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A Robust Fiber Bragg Grating Hydrogen Gas Sensor Using Platinum-Supported Silica Catalyst Film

Journal of Sensors ◽

10.1155/2018/5810985 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Marina Kurohiji ◽

Seiji Ichiriyama ◽

Naoki Yamasaku ◽

Shinji Okazaki ◽

Naoya Kasai ◽

...

Keyword(s):

Fiber Bragg Grating ◽

Gas Sensor ◽

Temperature Change ◽

Catalytic Combustion ◽

Room Temperature ◽

Precursor Solution ◽

Hydrogen Gas ◽

Combustion Heat ◽

Catalyst Film ◽

Sensor Device

A robust fiber Bragg grating (FBG) hydrogen gas sensor for reliable multipoint-leakage monitoring has been developed. The sensing mechanism is based on shifts of center wavelength of the reflection spectra due to temperature change caused by catalytic combustion heat. The sensitive film which consists of platinum-supported silica (Pt/SiO2) catalyst film was obtained using sol-gel method. The precursor solution was composed of hexachloroplatinic acid and commercially available silica precursor solution. The atom ratio of Si : Pt was fixed at 13 : 1. A small amount of this solution was dropped on the substrate and dried at room temperature. After that, the film was calcined at 500°C in air. These procedures were repeated and therefore thick hydrogen-sensitive films were obtained. The catalytic film obtained by 20-time coating on quartz glass substrate showed a temperature change 75 K upon exposure to 3 vol.% H2. For realizing robust sensor device, this catalytic film was deposited and FBG portion was directly fixed on titanium substrate. The sensor device showed good performances enough to detect hydrogen gas in the concentration range below lower explosion limit at room temperature. The enhancement of the sensitivity was attributed to not only catalytic combustion heat but also related thermal strain.

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