Ordered mesoporous NiFe2O4 with ultrathin framework for low-ppb toluene sensing

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2018,（3）
• 页码范围: 187-193
• 页数: 7页
• 语种: 英文

摘要

Highly sensitive and selective detection against specific target gases,especially at low-ppb (part per billion) level,remain a great number of challenges in gas sensor applications.In this paper,we first present an ordered mesoporous NiFe2O4 for highly sensitive and selective detection against low-ppb toluene.A series of mesoporous NiFe2O4 materials were synthesized by templating from mesoporous silica KIT-6 and its framework thickness was reduced from 8.5 to 5 nm by varying the pore size of KIT-6 from 9.4 to 5.6 nm,accompanied with the increase of the specific surface area from 134 to 216 m2 g 1.The ordered mesoporous NiFe2O4 with both ultrathin framework of 5 nm and large specific surface area of up to 216 m2 g-1 exhibits a highest response (Rgas/Rair-1 =77.3) toward 1,000 ppb toluene at 230 ℃ and is nearly 7.3 and 76.7 times higher than those for the NiFe2O4 replica with thick framework and its bulk counterpart respectively,which also possesses a quite low limit of detection (＜2 ppb),and good selectivity.