High benzene selectivity of mesoporous silicate for BTX gas sensing microfluidic devices.
The gas selectivities of highly ordered mesoporous silicates and commercially-obtained porous silicates with respect to benzene, toluene and xylene were studied. After studying the porosities, pore uniformities, and surface silanol structures of the silicates and their relationships to gas selectivity in detail, we found that we could achieve high benzene selectivity by controlling the micropore size (less than 1 nm). Concluding that mesoporous silicate has a suitable micropore size and structure for benzene selectivity, we also observed that mesoporous silicate SBA-16 exhibited a high (>6) benzene selectivity from toluene and xylene even in a pseudo-atmospheric environment. A benzene detection limit of about 100 ppb was achieved by introducing SBA-16 into a microfluidic device originally developed for the separate detection of benzene, toluene, and xylene gases.
Ueno
Yuko
Y
NTT Microsystem Integration Laboratories, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan. ueno@aecl.ntt.co.jp
Tate
Akiyuki
A
Niwa
Osamu
O
Zhou
Hao-Shen
HS
Yamada
Takeo
T
Honma
Itaru
I
D000395:Air Pollutants, Occupational / Q000032:analysis*; D001554:Benzene / Q000032:analysis*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods; D010316:Particle Size; D016062:Porosity; D012680:Sensitivity and Specificity; D017640:Silicates / Q000737:chemistry*; D013997:Time Factors; D014050:Toluene / Q000032:analysis; D014992:Xylenes / Q000032:analysis
D000395:Air Pollutants, Occupational; D017640:Silicates; D014992:Xylenes; D014050:Toluene; D001554:Benzene