Chemical Defect‐Driven Response on Graphene‐Based Chemiresistors for Sub‐ppm Ammonia Detection. (21st February 2022)

• Record Type: Journal Article
• Authors: Freddi, Sonia; Gonzalez, Miriam C. Rodriguez; Carro, Pilar; Sangaletti, Luigi; De Feyter, Steven
• Is Part Of: Angewandte Chemie. Volume 134:Number 16(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-02-21
• Subjects: Ammonia -- Chemical Grafting -- Gas Sensors -- Graphene; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202200115
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Gas sensors are essential in several fields and, in general, features such as high sensitivity, quick response, and fast recovery are required, along with low power consumption and low cost. Graphene is considered a promising material for gas sensing applications, its functionalization often being a requisite. In the present study, we developed competitive and promising gas sensors for ammonia detection. Interestingly, we present an easy and efficient method to functionalize graphene by using diazonium chemistry with different functional groups. Moreover, we prove the superior sensing capability of our covalently modified graphene layers. These experimental data have been consistently interpreted by theoretical calculations, which reveal a defect‐driven sensor's response to ammonia. These results open the possibility of a comprehensive design and use of these graphene‐based sensors in real applications. Abstract : Covalent functionalization of graphene leads to excellent sensitivity for ammonia. Quick response and recovery of the functionalized graphene layers are observed, and a sensitivity benchmarking with other graphene chemiresistors shows a superior sensitivity in the sub‐ppm range.