Polydiacetylene‐based selective NH₃ gas sensor using Sc₂O₃/GaN structures

Abstract

PDA(Polydiacetylene)‐supramolecules were successfully immobilized on the surface of Sc2O3/GaN/Sapphire structures for use as selective NH3 gas sensors. The Sc2O3 was epitaxially grown on GaN/Sapphire templates by molecular beam epitaxy (MBE) to replace the non‐uniform native Ga2O3. The GaN‐based PDA gas sensors showed excellent selectivity for ammonia detection after the end‐functional group was modified to respond to this specific gas species. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Novel semiconductor materials for the development of chemical sensors and biosensors: A review

“…Moreover, the aforementioned WBG materials have excellent reverse recovery characteristics, and for this reason they require less time and energy to return to the base line signal. In addition they are less susceptible to electromag- GaN [33][34][35][36][37][38][39][40][41][42] InN [43] AlN [44][45][46] SiC [47][48][49][50][51][52][53] Ion sensing…”

Colorimetric and Fluorometric Detection of Neomycin Based on Conjugated Polydiacetylene Supramolecules

“…Upon environmental stimulation, the blue PDAs can undergo a colorimetric transition from blue to red and a fluorescence enhancement. Utilizing the colorimetric and fluorogenic changes, some systems based on PDAs have been constructed to detect various targets,6–17 such as viruses,7 microorganisms,8 bacterial toxins,9 proteins,10 antigens/pathogens,11 DNAs,12 enzymes,13 membrane interaction,14 organic molecules,15 ions,16 and gases 17. In our previous report, the regularly arrayed hydrogen bonding of PDAs with phenolate as head groups can be destroyed upon the addition of surfactants with cationic head groups, producing notable optical changes 15b.…”

Fabrication of polydiacetylene particles using a solvent injection method

“…24 The detection of ammonia via carboxy-terminated PDA vesicles has been documented in various contexts and formats. 21,25,26 Ammonia is a strong base and increases the pH of the PDA environment which encourages dissociation of carboxylic acid head groups. The negatively charged carboxylate head groups repel each other and induce structural rearrangement in the vesicle that produces a blue to red color change.…”