University of Oulu

Zhou, J., Shokouh, S. H. H., Cui, L., Järvinen, T., Pitkänen, O., Lv, Z.-P., & Kordas, K. (2023). An ultra-sensitive NH 3 gas sensor enabled by an ion-in-conjugated polycroconaine/Ti 3 C 2 T x core–shell composite. Nanoscale Horizons, 8(6), 794–802.

An ultra-sensitive NH₃ gas sensor enabled by an ion-in-conjugated polycroconaine/Ti₃C₂Tₓ core–shell composite

Saved in:
Author: Zhou, Jin1; Shokouh, Seyed Hossein Hosseini1; Cui, Linfan2;
Organizations: 1Microelectronics Research Unit, Faculty of Information Technology and Electrical Engineering, University of Oulu, P.O. Box 4500, FIN-90014 Oulu, Finland
2Department of Chemical and Metallurgical Engineering, Aalto University, FIN00076 Aalto, Finland
3Department of Applied Physics, Aalto University, FIN-00076 Aalto, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 2.8 MB)
Persistent link:
Language: English
Published: Royal Society of Chemistry, 2023
Publish Date: 2023-09-14


MXenes are emerging sensing materials due to their metallic conductivity and rich surface chemistry for analytes; they, however, suffer from poor stability. Incorporation with functional polymers can largely prevent the performance decay and enhance the sensing performance. Herein, we demonstrate a core–shell composite, Ti₃C₂Tₓ@croconaine (poly(1,5-diaminonaphthalene-croconaine), PDAC) prepared by a facile in situ polymerization reaction, suitable for NH₃ detection. Compared to pristine Ti₃C₂Tₓ, the sensor made of a Ti₃C₂Tₓ–polycroconaine composite exhibits a significantly enhanced sensitivity of 2.8% ppm⁻¹ and an estimated achievable limit of detection of 50 ppb. The improved sensing performance could be attributed to the presence of PDAC facilitating the adsorption of NH₃ and changing the tunneling conductivity between Ti₃C₂Tₓ domains. Density functional theory (DFT) calculations reveal that the adsorption energy of NH₃ on PDAC is the highest among the tested gases, which supports the selectivity of the sensor to this analyte. Benefiting from the protection conferred by the PDAC shell, the composite has a reliable operation period of at least 40 days. In addition, we demonstrated a flexible paper-based sensor of the Ti₃C₂Tₓ@PDAC composite, without attenuated performance upon mechanical deformation. This work proposed a novel mechanism and a feasible methodology to synthesize MXene–polymer composites with improved sensitivity and stability for chemical sensing.

see all

Series: Nanoscale horizons
ISSN: 2055-6756
ISSN-E: 2055-6764
ISSN-L: 2055-6756
Volume: 8
Issue: 6
Pages: 794 - 802
DOI: 10.1039/d2nh00591c
Type of Publication: A1 Journal article – refereed
Field of Science: 216 Materials engineering
213 Electronic, automation and communications engineering, electronics
Copyright information: This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.