Flexible CO2 sensor architecture with selective nitrogen functionalities by one-step laser-induced conversion of versatile organic ink

Abstract

Nitrogen-doped carbons (NC) are a class of sustainable materials for selective CO2 adsorption. We introduce a versatile concept to fabricate flexible NC-based sensor architectures for room-temperature sensing of CO2 in a one-step laser conversion of primary coatings cast from abundant precursors. By the unidirectional energy impact in conjunction with depth-dependent attenuation of the laser beam, a layered sensor heterostructure with porous transducer and active sensor layer is formed. Comprehensive microscopic and spectroscopic cross-sectional analyses confirm the preservation of a high content of imidazolic nitrogen in the sensor. The performance was optimized in terms of material morphology, chemical composition, and surface chemistry to achieve a linear relative resistive response of up to ∆R/R0 = -14.3% (10% of CO2). Thermodynamic analysis yields ΔadsH values of -35.6 kJ·mol-1 and 34.1 kJ·mol 1 for H2O and CO2, respectively. The sensor is operable even in humid environments (e.g., ∆R/R0,RH=80% = 0.53%) and shows good performance upon strong mechanical deformation.

A bio-inspired and switchable H+/OH− ion-channel for room temperature exhaled CO2 chemiresistive sensing

“…The results showed that the average concentration of human exhaled CO 2 aer exercise was around 12.78% higher than before exercise, which clearly shows that the CO 2 concentration in exhalation is related to the metabolism of the human body. 62,63 The above evidence suggests that this bio-inspired CSPH ion channel chemiresistive sensor has great potential for application in monitoring human exhalation.…”

Laser-Induced Nitrogen Fixation

“…To address the above challenges, we analyze a laser-pulse driven chemical conversion system operating under 1.0 bar N 2 pressure (18,19), which enables a one-step, solvent-free transformation of metal oxide to metal nitride, that subsequently can be hydrolyzed to generate ammonia. In our approach, three advantages are met in the laser induction reaction system: i) laser-induction technology satisfies the demand of small-scale, distributed production of chemicals with the energy converted from broad-band solar radiation (20,21); ii) an important characteristic of the focused light is the energy highly concentrated in certain space, which allows non-linear, non-equilibrium chemistry with a potentially high rate for ammonia production; iii) different from the electrochemical method and photocatalysis, in which interfacial transport and diffusion of substances, solvents stability, etc.…”

Modulating between 2e− and 4e− pathways in the oxygen reduction reaction with laser-synthesized iron oxide-grafted nitrogen-doped carbon

“…However, by the degree of graphitization a reaction temperature gradient of <500 °C and >1500 °C between the lower and the upper layer of the LP-NC film are assumed. (37) The difference between the two routes lies in the prearrangement and the nature of the iron precursors in the primary inks.…”