Issue 20, 2024

Investigation on acceptordonor co-doped SnO2 nanoparticles enriched with oxygen vacancies: a capacitive humidity sensor for respiration detection

Abstract

In this work, we develop a novel capacitive humidity sensor based on Al–Si acceptor–donor co-doped SnO2 for real-time monitoring of ambient humidity and human respiration. XRD measurements reveal that all samples exhibit a tetragonal rutile phase and the crystallite size of SnO2 decreases with increasing Al–Si content. The high intensity of the Raman peak at 762 cm−1 confirms the presence of bridging mode oxygen vacancies in (Al + Si)0.02Sn0.98O2. The EPR results show that the amount of singly ionized oxygen vacancies increases after the introduction of Al–Si. Both types and amounts of oxygen vacancy defects are particularly sensitive to the adsorption of water molecules. Moreover, according to DFT calculations, the contribution of the Si 3s orbital and Al 3s orbital to the band edge verifies the formation of acceptor–donor complexes in Al–Si co-doped SnO2. The humidity sensing results reveal that the (Al + Si)0.02Sn0.98O2 humidity sensor shows high sensitivity (S = 839), low hysteresis (1.94%) and fast response/recovery times (25 s/5 s). The respiratory intervals during shallow, medium and deep breathing states of (Al + Si)0.02Sn0.98O2 were measured at 2.8 s, 3.8 s and 4.5 s, respectively. The chemical mechanism for the enhancement of humidity sensing performance corresponding to the oxygen vacancy defects induced by Al–Si interplay is proposed.

Graphical abstract: Investigation on acceptor–donor co-doped SnO2 nanoparticles enriched with oxygen vacancies: a capacitive humidity sensor for respiration detection

Article information

Article type
Paper
Submitted
18 mar. 2024
Accepted
27 abr. 2024
First published
30 abr. 2024

Phys. Chem. Chem. Phys., 2024,26, 14582-14593

Investigation on acceptordonor co-doped SnO2 nanoparticles enriched with oxygen vacancies: a capacitive humidity sensor for respiration detection

Y. Ding, Y. Chen and M. Wang, Phys. Chem. Chem. Phys., 2024, 26, 14582 DOI: 10.1039/D4CP01141D

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements