Annealing plays a crucial role for in enhancing the gas sensing properties of MOF-derived TiO (MIL-125). Generally, TiO transforms into different polymorphs (anatase, rutile, and brookite) during annealing, each with unique crystal structures and gas sensing properties. The aim of this research was to investigate the impact of annealing (500-650 °C) on the properties of MIL-125, which had not been previously studied. Through precise control, a 3D nanodisk morphology was obtained, where the MIL-125 surface gradually becomes rough at 600 °C (MT600). At 650 °C (MT650), anatase transforms completely into rutile, resulting in significant collapse and a decrease in diameter size from 700 nm to 300 nm. The XPS and EPR study showed that the MIL-125 nanodisks contain high amount of oxygen vacancies, thus giving higher response to various gases, specifically to acetone. The MT600 sensor maintained a good sensor response (for instance S∼21 toward 500 ppm acetone) at 250 °C for isntance SR. Even at 1 ppm, it exhibited an S value of ∼6.7. A fast response (T ∼13 s) and recovery time (T ∼12 s) of MT600 sensor at 100 ppm acetone was obtained. The gas sensing mechanism is thoroughly discussed, and the electron migration process in acetone detection is analyzed, offering new sensitive materials and insights for improving metal-oxide-semiconductor gas sensors.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.talanta.2025.127547 | DOI Listing |
ACS Sens
January 2025
National Engineering Research Center of Fiber Optic Sensing Technology and Networks, Wuhan University of Technology, Wuhan 430070, China.
This paper presents a compact all-fiber multicomponent gas Raman probe using a dual-fiber architecture within a platinum-coated capillary. The probe eliminates the need for conventional optical components like filters and dichroic mirrors by strategically employing metal coating on the excitation fiber's surface to suppress interference signals. A detailed analysis of the silica Raman signal and fluorescence propagation within the system facilitated this design.
View Article and Find Full Text PDFNat Commun
January 2025
School of Emergent Soft Matter, South China University of Technology, Guangzhou, China.
Radioactive molecular iodine (I) is a critical volatile pollutant generated in nuclear energy applications, necessitating sensors that rapidly and selectively detect low concentrations of I vapor to protect human health and the environment. In this study, we design and prepare a three-component sensing material comprising reduced graphene oxide (rGO) as the substrate, silver iodide (AgI) particles as active sites, and polystyrene sulfonate as an additive. The AgI particles enable reversible adsorption and conversion of I molecules into polyiodides, inducing substantial charge density variation in rGO.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Department of Chemistry, Madanapalle Institute of Technology & Science, Kadiri Road, Angallu, Madanapalle, 517325, Annamayya District, Andhra Pradesh, India.
A new Rhodamine functionalised Schiff Base sensor 3',6'-bis(diethylamino)-2-((4-hydroxybenzylidene)amino)spiro[isoindoline-1,9'-xanthen]-3-one (SBRB1) was designed and synthesized. The recognition ability of sensor SBRB1 towards Hg was studied by using UV-Vis and fluorescence spectroscopy. The fluorescence results showed that the sensor SBRB1 has specific selectivity as well as sensitivity towards Hg among other competitive metal ions as the fluorescence intensity at 479 nm quenched only in the presence of Hg.
View Article and Find Full Text PDFEnviron Monit Assess
January 2025
Department of Environmental Management, Institute of Environmental Engineering, RUDN University, Miklukho-Maklaya Street, 117198, Moscow, Russia.
Globally, agricultural lands are among the top emitters of greenhouse gases (GHGs), responsible for over 20% of total greenhouse gas (GHG) emissions. Climatic conditions, an acute challenge in sub-Saharan Africa (SSA), where access to mitigation technologies remains limited, have heavily influenced these lands. This study explores GHG contributions from crop production and their devastating and deteriorating impacts on the economy and environment and proposes a sustainable solution.
View Article and Find Full Text PDFACS Nano
January 2025
SKKU Advanced Institute of Nanotechnology (SAINT) and Department of Nano Science and Technology, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Alternating- and direct-current (ADC) bipolar electropolymerization (EP) offers an efficient and scalable approach for the lateral synthesis of conjugated macromolecules, enabling the simultaneous polymerization and deposition of large conducting polymer films with intriguing fractal-like ramified topographies onto arbitrary insulating substrates under remote control. In this study, we presented the remote synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT):anion sensing films on a plastic substrate, aimed at their use in flexible nitrogen dioxide (NO) gas sensors. Notably, the PEDOT:ClO films exhibited excellent gas-sensing characteristics, with a sensitivity of 54.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!