Inside Cover: Optimized Synthesis of Solution‐Processable Crystalline Poly(Triazine Imide) with Minimized Defects for OLED Application (Angew. Chem. Int. Ed. 3/2022)

Abstract

Poly(triazine imide)…i of the family of graphitic carbon nitrides and its graphitic morphology allows exfoliation the material into solution-processable layers,while at the same time reducing migration and drift of chemically bonded dopants.Ateam of researchers from Humboldt-Universitätz uB erlin, Carl von Ossietzky UniversitätOldenburg,and Helmholtz-Zentrum Berlin (HZB) constructed the first thin layer, organic light emitting device (OLED) with asolution-processed graphitic organic material as am etal-free emission layer. Ford etails see the Research Article by Michael J. Bojdys et al. (e202111749).

Size Effects of the Anions in the Ionothermal Synthesis of Carbon Nitride Materials

“…We attribute the additional broad peak at 27° 2θ to the emergence of the glassy, secondary brown phase that is formed because of carbonization of crystalline melem hydrate into randomly stacked, π‐conjugated fragments. A similar behavior was reported previously for carbonization products of poly(triazine imide) in a LiBr/KBr eutectic [16] . As expected, melem hydrate undergoes a reversible phase change to melem during vacuum drying at 200 °C for 24 h (Figure S9) [29] …”

“…A similar behavior was reported previously for carbonization products of poly(triazine imide) in a LiBr/KBr eutectic. [16] As expected, melem hydrate undergoes a reversible phase change to melem during vacuum drying at 200 °C for 24 h (Figure S9). [29] Scanning force microscopy (SFM) shows a high degree of order at the surface of melem hydrate single crystals (Figure S10).…”

Elucidation of Metal Local Environments in Single‐Atom Catalysts Based on Carbon Nitrides

“…However, the demonstrated effectiveness of 15 N analysis makes it broadly applicable to SACs based on carbon nitrides, and the study of other nuclei (e.g., 13 C, 17 O, and 31 P) could give insights into metal coordination in other hosts. [ 20 ]…”

“…However, the demonstrated effectiveness of 15 N analysis makes it broadly applicable to SACs based on carbon nitrides, and the study of other nuclei (e.g., 13 C, 17 O, and 31 P) could give insights into metal coordination in other hosts. [20] DFT enables the exploration of precisely defined structural models of virtually any SAC and has provided an advanced understanding of the properties of metal atoms stabilized on carbon nitrides in distinct catalytic applications. [17] A positive outcome of this study is the good agreement obtained between experimentally evidenced and DFT simulated structures, providing the most robust benchmark to date for the structural assumptions underlying the models.…”

“…The TEKPol radical, introduced in the sample as a 1,1,2,2-tetrachloroethane (TCE) solution, was used to drive polarization transfer through the protons of the solvent to surface 15 N nuclei. [20] By enhancing signals from TCE and surface 15 N nuclei 24-fold and 17-fold, respectively, the use of DNP-SENS (surface-enhanced NMR spectroscopy) overcomes known NMR sensitivity issues for 15 N nuclei (low gamma, 0.4% natural abundance), [21] reducing measurement times by 300-fold, and thereby enabling the study of materials without isotopic enrichment. The spectra observed for PTI and HC-PTI materials further evidenced the predominance of two nitrogen species at ≈130 and 203 ppm (Figure 1e).…”