Nanomaterials for sensing of formaldehyde in air: principles, applications, and performance evaluation.

Despite the improvement in sensing technologies, detection of small and highly reactive molecules like formaldehyde remains a highly challenging area of research. Applications of nanomaterials/nanostructures and their composites have increased as effective sensing platforms (e.g., reaction time, sensitivity, and selectivity) for the detection of aqueous or gaseous formaldehyde based on diverse sensing principles. In this review, the basic aspects of important nanomaterial-based sensing systems (e.g., electrochemical, electrical, biological, and mass variation sensors) were evaluated in relation to performance, cost, and practicality of sensing gas phase formaldehyde. Accordingly, existing knowledge gaps in such applications were assessed in various respects along with suitable recommendations for building a new roadmap for the expansion of chemical sensing technology of gas phase formaldehyde.This study was supported by a grant from the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, and Future Planning (No. 2016R1E1A1A01940995). This research also acknowledges the support made by the R&D Center for Green Patrol Technologies through the R&D for Global Top Environmental Technologies funded by the Ministry of Environment (MOE) as well as support made by the Korea Ministry of Environment (MOE) (No. 2015001950001) as part of "The Chemical Accident Prevention Technology Development Project". D.K. acknowledges the support of Science and Engineering Research Board, Government of India, for providing financial assistance under the young scientist scheme (No. YSS/2015/000212)