Figures (4)  Tables (8)

    • Figure 1. 

      Functional diagram of MZI interferometer hydrogen sensors.

    • Figure 2. 

      Functional diagram of a micro-mirror hydrogen sensor.

    • Figure 3. 

      Functional diagram of an evanescent field hydrogen sensor.

    • Figure 4. 

      Functional diagram of fiber grating hydrogen sensors.

    • Gas stateNatural gasHydrogenPropane
      Diffusion state1.03.80.63
      Laminar condition1.01.261.38
      Turbulent condition1.02.830.6

      Table 1. 

      Leakage rates of hydrogen and propane relative to natural gas.

    • OrderOrganizationStandard numberStandard names
      1Standardization Administration of the People's Republic of China (SAC)GB/T 23751.1-2009Micro fuel cell power systems—Part 1: Safety
      2GB/T 24549-2009Fuel cell electric vehicles-Safety requirements
      3GB/T 27748.1-2017Stationary fuel cell power systems—Part 1:safety
      4GB/T 29729-2013Essential requirements for the safety of hydrogen systems
      5GB/T 30084-2013Portable fuel cell power system-Safety
      6GB/T 31036-2014Proton exchange membrane fuel cell backup power system-Safety
      7GB/T 31037.1-2014Fuel cell power system used for industrial lift truck applications—Part 1: Safety
      8GB/T 31139-2014Safety technical regulations for mobile hydrogen refueling facility
      9GB/T 34539-2017Safety requirements on hydrogen-oxygen generator
      10GB/T 34544-2017Safety test methods for onboard low pressure hydrogen storage devices for small fuel cell vehicles
      11GB/T 34583-2017Safety technical requirements for hydrogen storage devices used in hydrogen fuelling station
      12GB/T 34584-2017Safety technical regulations for hydrogen refueling station
      13GB/T 36288-2018Fuel cell electric vehicles-Safety requirement of fuel cell stack
      14International Organization for Standardization (ISO)ISO/TR 15916:2015Basic considerations for the safety of hydrogen systems
      15ISO 16110-1:2007Hydrogen generators using fuel processing technologies Part1: Safety
      16ISO/TS 19883:2017Safety of pressure swing adsorption systems for hydrogen separation and purification
      17ISO 21266-1:2018Road vehicles — Compressed gaseous hydrogen (CGH2) and hydrogen/natural gas blends fuel systems—Part 1: Safety requirements
      18ISO 23273:2013Fuel cell road vehicles — Safety specifications — Protection against hydrogen hazards for vehicles fuelled with compressed hydrogen
      19American National Standards Institute (ANSI)ANSI/AIAAG-095A-2017Hydrogen and Hydrogen Systems

      Table 2. 

      Overview of hydrogen safety standards at home and abroad.

    • StandardScope of
      applications      		Gas cylinder test itemsNormative requirements
      of the industrial chain      		Other quality assurance terms
      GB/T 35544-2017Aluminum liner carbon fiber fully wound gas cylinderWinding layer mechanical property test, winding layer appearance inspection, hydraulic pressure test, air tightness test, hydraulic burst test, normal temperature pressure cycle test, fire test, extreme temperature pressure cycle test, accelerated stress rupture test, crack tolerance test, environmental test, drop test, hydrogen gas cycle test, gunshot test, durability test, performance testThe packaging, transportation and storage of cylinders after the completion of the manufacture are specified, without involving the storage and transportation of relevant raw materialsOnly manufacturing units are required to provide mass inspection quality certificates
      ANSI HGV2-2014
      and ISO/CD 19881:2015      		Four types of gas cylindersEnvironmental cycling test, extreme temperature cycling test, hydraulic burst test, defect tolerance test, drop test, fire test, accelerated stress fracture test, high strain rate impact test, penetration test, torque test, hydrogen cycle test, leakage test before fractureNo related termsThe manufacturing units needs to establish and operate a quality management system in accordance with the provisions of ISO9001.

      Table 3. 

      Main differences between domestic and foreign standard clauses.

    • AuthorPublishedSensor headPerformanceReference
      Butler & Ginley198810 nm Ti + 10 um PdDetecting concentration (DC) > 0.6%, response time (RT): 3 min[44]
      Zeakes et al.199450 um Fabry-Perot cavityRT: 5 s, Sensitivity: 35 ppm/%, poor repeatability[45]
      Maciak & Opilski2007TiO2 film + NiOx filmDC < 4%, RT < 1 min, Recovery time (RCT) < 1 min, excellent stability[46]
      Wang et al.2012Pd-coated open air-cavitySensitivity: 155 pm/%, Weak anti-interference ability[47]
      Kim et al.2012Ni (adhesion layer) +
      Pd(sensing layer)      		DC: 4%, RT: 50 s, Sensitivity: 0.7 nm to 4% H2[48]
      Gu et al.2015Pd-Au alloy nanowireDC: 0−20%, RT: 200 s, Sensitivity: 0.175 nm/%, RCT: 400 s[43]
      Xu et al.2017Hollow core fiber + Single mode fiber (SMF) + Fiber Bragg grating DC: 0.2%, RT < 30 s, Sensitivity: 0.85 nm/%, greet repeatability[49]
      Liu et al.2019Nanopatterned Pd filmDC: 1%−3%, RT: ~25 s, Sensitivity: ~1.3 nm/%[50]

      Table 4. 

      Performance comparison of interferometer hydrogen sensors.

    • AuthorPublished Sensor headPerformanceReference
      Butler199110 nm Pd filmDetecting concentration (DC): 0.2%−2%, sensitivity: ~0.035/%[51]
      Jung et al.1998Pd alloy filmDC: ~4%, RT: ~20 s, great repeatability[52]
      Bévenot et al.200013 nm Pd metal layerDC: 1%−17%, RT < 5 s, poor stability[53]
      Westerwaal et al.2013 Pd81Au19 + TiDC: 0.5%−4%, RT < 15 s, good hydrogen selectivity and repeatability[54]

      Table 5. 

      Performance comparison of micro-mirror hydrogen sensors.

    • AuthorPublishedSensor headPerformanceReference
      Tabib-Azar et al.1999Pd film with 10 nm thickness and 1.5 cm lengthDetecting concentration (DC): 0.2%−6%, response time (RT): 20−30 s, great repeatability[56]
      Sekimoto et al.2000Pd/WO3 composite filmDC: ~0.2%, RT: 20 s, great repeatability[57]
      Villatoro et al.2003SMF + Pd filmDC: ~0−10.5%, RT < 100 s, Recovery time (RCT): 75 s[58]
      Villatoro et al.2005Multimode tapered fiber + Pd filmWhen the thickness of Pd film is 4 nm, the response time of the sensor with a concentration of 3.5% is 10 s[59]
      Monzon-Hernandez et al,2010Au-Pd nanoparticle filmThe response time of the sensor to 4% hydrogen is 5s, poor sensitivity[60]
      Li et al.2018Pd +Poly(methyl methacrylate) DC: 0.2%−1%, RT: 5 s, sensitivity: 5.58 nm/%[61]

      Table 6. 

      Performance comparison of evanescent field hydrogen sensors.

    • AuthorPublishedSensor headPerformanceReference
      Chadwick & Gal1993Pd/Ni alloy filmDC: 0.1%−10%, response time (RT): ~30 s[62]
      Perrotton et al.201135 nm Ag/100 nm SiO2/3.75 nm PdDC: ~4%, RT < 15 s[63]
      Wang et al.201335 nm Ag/100 nm SiO2/180 nm WO3/3 nm PtDC: < 2%, sensitivity: 17.4 nm at 2%[64]
      Hosoki et al.201425 nm Au/60 nm Ti2O5/10 nm PdDC: 4%, RT: 8 s, sensitivity: 7 nm/%[65]
      Beni et al.2019WO3/Pd + Y/Pd nano-diskDC: 0−100%, RT: 10 s, sensitivity: 60 nm at 4%,
      RCT: 5 min      		[66]

      Table 7. 

      Performance comparison of SPR hydrogen sensors.

    • AuthorPublishedSensor headPerformanceReference
      Sutapun et al.1999Fiber Grating + 560 nm PdDetecting concentration (DC): 0.8%−1.3%, response time (RT): 10 min[68]
      Aleixandrea et al.2005Fiber grating + 5 nm Pd filmDC: ~0.8%−1.3%, sensitivity: 8.4 pm/%[69]
      Trouillet et al.20055 nm Pd filmDC: < 4%, sensitivity: 14 pm at 4%[70]
      Schroeder et al.2009Pd film + fiber gratingDC: 0−2%, sensitivity: 33 pm/%[71]
      Yan et al.2016100 nmAu/50 nm WO3/ 30 nm PdDC: 0.086 cc, RT: 4 s, sensitivity: 70 nm/cc[72]

      Table 8. 

      Performance comparison of fiber grating hydrogen sensors.