3D Hollow Quasi-Graphite Capsules/Polyaniline Hybrid with a High Performance for Room-Temperature Ammonia Gas Sensors

Abstract

Designing sensing materials with novel morphologies and compositions is eminently challenging to achieve high-performance gas sensor devices. Herein, an in situ oxidative polymerization approach is developed to construct three-dimensional (3D) hollow quasi-graphite capsules/polyaniline (GCs/PANI) hierarchical hybrids by decorating protonated PANI on the surface of GCs; as a result, an immensely active and sensitive material was developed for sensing ammonia gas at room temperature. Moreover, the GCs possessed a capsule-like hollow/open structure with partially graphitized walls, and PANI nanospheres were uniformly decorated on the GC surfaces. Furthermore, the inflexible and rigid 3D ordered chemistry of these materials provides the resulting hybrids with a large interfacial surface area, which not only allows for rapid adsorption and charge transfer but also provides the necessary structural stability. The 3D hollow GCs/PANI hybrids exhibit excellent performance; the GCs/PANI-3 hybrid is highly sensitive (with a response value of 1.30) toward 10 ppm NH 3 gas and has short response and recovery times of 34 and 42 s, respectively. The GCs/PANI-3 hybrid also demonstrates a good selectivity, repeatability, and long-term stability, which are attributed to the substantial synergistic effect of the GCs and PANI. The design of such a unique 3D ordered framework provides a promising pathway to achieve room-temperature gas sensors for commercial applications.

Superior Fe x N electrocatalyst derived from 1,1′-diacetylferrocene for oxygen reduction reaction in alkaline and acidic media

“…Some studies have shown that iron can promote the graphitization of sp 2 carbon and adjust the electronic state of the sp 2 carbon [31,32]. The graphitization of carbon is also conducive to the electron transfer of the catalyst and solidifies the nano-catalyst to reduce the agglomeration of the catalyst [25,33], and all these advantages make it have an excellent ORR activity. It has also been found that the catalytic activity of Fe-based compounds is directly related to the size of the materials [34,35].…”

Preparation and Characterization of PANI@NiO Visible Light Photocatalyst for Wastewater Treatment

“…The existence of PANI and NiO in our synthesized hybrid composite were further demonstrated by the RAMAN spectra shown in figure 2. For PANI the peaks at 416, 522, 573, 775, 1167, 1218, 1409, 1495 and 1605 cm −1 were observed and assigned to out of plane C−H wagging, deformation of polaronic amine, deformation of bipolaronic amine, C−H out of plane bending of quinoid ring, C−H bending of quinoid ring, C−N stretching vibration of cationic radical species, C−N + stretching vibration of cationic radical species, C=N stretching of quinoid ring, C−C stretching vibration of quinoid ring [28–33] …”

Graphene, an Interesting Nanocarbon Allotrope for Biosensing Applications: Advances, Insights, and Prospects

“…[15][16][17][18][19][20][21][22] All these studies contributed to scaling up production of sustainable, efficient and cost-effective quality G sheets. [23][24][25] Innovative methods such as electrochemical reduction of exfoliated G oxide (GO) (which is oxidative and water-soluble form of G), 5 epitaxial growth in GP or in metals via chemical vapor deposition (CVD), facilitated this production [26][27][28][29][30][31][32] ( Figure 4). In particular, G have excited many researchers and industrials interested in developing nanobiosensors since Sir Geim and Sir Novoselov were awarded the 2010 Nobel Prize in Physics.…”