Preparation of honeycomb films from nitryl poly(ether ether ketone)s via water‐droplet templating

Abstract

The fabrication of honeycomb-patterned films from nitryl poly(ether ether ketone)s (PEEK-NO 2 ) in a high-humidity atmosphere was reported in this article. PEEK-NO 2 was prepared through acid (nitric acid and sulfuric acid) nitration from poly(ether ether ketone)s (PEEK). The obtained polymer, which was characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) showed excellent solubility and thermal stability. Some influence factors on the pattern formation and the fabrication of the porous structure, such as the solution concentration, the solvent, and the atmosphere humidity, were investigated. The results showed that with the increase of the solution concentration, the aperture of the film diminished gradually; the lower the solventś boiling point were, the smaller the filmś apertures were and the more regular the poreś arrange ; only under high-humidity circumstances could obvious and ordered honeycomb films be formed.

Ultrathin In2O3 Nanosheets toward High Responsivity and Rejection Ratio Visible‐Blind UV Photodetection

“…Therefore, we will focus on the performance of ultrathin In 2 O 3 NSs PEC PDs at 0.4 V. Furthermore, ultrathin In 2 O 3 NSs PEC PDs show good reproducibility for different devices with small deviations, as shown in Tables S2–S4, Supporting Information. As shown in Figure 2b,c, ultrathin In 2 O 3 NSs PEC PDs show an outstanding photoresponse to 254 nm with an ultrahigh R of 172.36 mA W −1 and a remarkable D * of 4.43 × 10 11 Jones under 254 nm irradiation at 0.4 V, respectively, which surpass all recently reported ultrathin nanomaterial‐based aqueous‐type PEC UV PDs [ 31–49 ] and are comparable with the record‐high performance of recently reported PEC UV PDs, [ 17 ] as shown in Table S9, Supporting Information. The ultrahigh UV detection capability and the operation in weak alkaline electrolyte indicate that ultrathin In 2 O 3 NSs hold great prospects for underwater UV communication [ 12 ] (more detailed comparison in Table S6, Supporting Information).…”

“…The improved spectral selectivity is attributed to the wider bandgap of ultrathin In 2 O 3 NSs originating from the quantum confinement effect. [ 27 ] The spectral selectivity and R of ultrathin In 2 O 3 NSs PEC VBUV PDs outperform most reported aqueous‐type PEC VBUV PDs, [ 26,44–48 ] as shown in Figure 3c, demonstrating their great potential in VBUV detection.…”

Achieving Record High External Quantum Efficiency >86.7% in Solar‐Blind Photoelectrochemical Photodetection

“…Figure 5f displays the device performance and recently reported aqueous‐type PEC photodetectors, and the calculated EQE values of these devices are summarized in Table S2, Supporting Information. [ 10–12,59–68 ] Impressively, our device with Rh–Cr 2 O 3 hybrid modification exhibits relatively fast response speed, outperforming most photodetectors. Most importantly, as shown in Table S2, Supporting Information, the as‐fabricated device shows one of the highest responsivities with an EQE up to 86.7%, suggesting the significant role of Rh–Cr 2 O 3 hybrid co‐catalyst to improve device performance.…”

Enabling Broadband Solar‐Blind UV Photodetection by a Rare‐Earth Doped Oxyfluoride Transparent Glass‐Ceramic

“…Solar‐blind UV light, that is, far UV and vacuum UV light with a wavelength of less than 0.28 µm, is absorbed by atmospheric ozone and water vapor and cannot reach the Earth's surface. [ 1–13 ] The background noise of the solar‐blind UV is small, and it is almost not interfered by solar radiation in the near‐surface space. Therefore, the photodetector working in this spectral range has the advantages of low noise, anti‐interference, and high sensitivity, and has a wide range of application value in military, communications, and civilian fields such as flame sensing, UV communication, ozone detection, and missile attack warning.…”