Ru(Phen)(bpy) 2 (1) and its new derivatives (2-5) with pyrenyl or ethynylated pyrene and phenyl units appended to the 3-position of the phenanthroline (Phen) ligand were prepared and these complexes generate long-lived room temperature phosphorescence in the red and near IR range (600-800 nm). The photophysical properties of these complexes were investigated by UV-Vis absorption, luminescence emission, transient absorption spectra and DFT/TDDFT calculations. We found the luminescence lifetime (s)can be drastically extended by ligand modification (increased up to 140-fold), e.g. s ¼ 58.4 ms for complex 3 (with pyrenyl ethynylene appendents) was found, compared to s ¼ 0.4 ms for the reference complex 1. Ethynylated phenyl appendents alter the s also (complex 2, s ¼ 2.4 ms). With pyrenyl appendents (4 and 5), lifetimes of 2.5 ms and 9.2 ms were observed. We proposed three different mechanisms for the lifetime extension of 2, 3, 4 and 5. For 2, the stabilization of the 3 MLCT state by p-conjugation is responsible for the extension of the lifetime. For 3, the emissive state was assigned as an intra-ligand (IL) long-lived 3 p-p* state ( 3 IL/ 3 LLCT, intraligand or ligand-to-ligand charge transfer), whereas a C-C single bond linker results in a triplet state equilibrium between 3 MLCT state and the pyrene localized 3 p-p* triplet state ( 3 IL, e.g. 4 and 5). DFT/TDDFT calculations support the assignment of the emissive states. The effects of the lifetime extension on the oxygen sensing properties of these complexes were studied in both solution and polymer films. With tuning the emissive states, and thus extension of the luminescence lifetimes, the luminescent O 2 sensing sensitivity of the complexes can be improved by ca. 77-fold in solution (I 0 /I 100 ¼ 1438 for complex 3, vs. I 0 /I 100 ¼ 18.5 for complex 1). In IMPES-C polymer films, the apparent quenching constant K SV app is improved by 150-fold from 0.0023 Torr À1 (complex 1) to 0.35 Torr À1 (complex 3). The K SV app value of complex 3 is even higher than that of PtOEP under similar conditions (0.15 Torr À1 ).

Three microporous polyimides, MPI-1, MPI-2, and MPI-3, with uniform pores were synthesized via one-pot polycondensation from tetrakis(4-aminophenyl)methane, tris(4-aminophenyl)amine and 1,3,5tris(4-aminophenyl)benzene with pyromellitic dianhydride, respectively. The amorphous networks exhibit excellent thermal stability, large BET surface areas up to 1454 m 2 g −1 , and narrow pore size distribution in the range from 5 to 6 Å. Their adsorption−desorption isotherms of CO 2 are reversible, and the CO 2 uptakes at 273 K and 1 bar are up to 16.8 wt %. Moreover, based on the ratios of initial slopes of isotherms, the CO 2 /N 2 and CO 2 /CH 4 separation factors are as high as 102 and 12, respectively. The above CO 2 adsorption and separation properties are attributed to the presence of abundant electron-rich heteroatoms in the polyimide networks and the unifrom ultralmicroporous structures. In addition, for MPI-1, the adsorption capacity of benzene vapor is 119.8 wt %, while the separation factors of benzene over nitrogen and water reach 342 and 28, respectively. The outstanding selective adsorptions of CO 2 gas and benzene vapor endow the microporous polyimides with promising potential in CO 2 capture and separation as well as air-and water-cleaning applications.

Tetraphenyladamantane-based polyaminals with ultrasmall pore, large specific surface area and abundant CO2-philic aminal groups are successfully synthesized, which exhibit simultaneously high CO2 adsorption capacity of 17.6 wt % (4.0 mmol g–1, 273 K/1.0 bar) and high adsorption selectivities of CO2/N2 (104) and CO2/CH4 (24). Especially, at the low pressure, e.g., 0.15 bar, the CO2 uptake at 273 K can reach 8.7 wt % (1.97 mmol g–1). The adsorption/selectivity properties are superior to most of microporous organic polymers (MOPs) reported in the literature. Besides the outstanding CO2-capturing ability, the polymers also possess high uptakes of benzene and cyclohexane vapors up to 72.6 and 52.7 wt %, respectively. In addition, the effects of reaction activity and type of amino groups as well as the size and shape of building blocks on porous architecture of microporous polyaminals are studied. The disclosed results are helpful for the deep understanding of pore formation and interconnecting behavior in MOPs and therefore are of significant importance for the synthetic control of MOPs for a specific application in gas storage and capture of organic vapors.

A consolidated ionothermal strategy was developed for the polymerization of thermally unstable nitriles to construct high performance materials with permanent porosity, and carbazole, dibenzofuran, and dibenzothiophene were separately introduced into covalent triazine-based networks to investigate the effects of heterocycles on the gas adsorption performance. Three nitriles, namely 3,6-dicyanocarbazole, 3,6-dicyanodibenzofuran, and 3,6-dicyanodibenzothiophene, were designed and synthesized, which were readily converted to heat-resistant intermediates at a moderate temperature and then polymerized to create highly porous poly(triazine) networks instead of the traditional one-step procedure. This documents an improved strategy for the successful construction of heterocyclic-functional triazine-based materials. The chemical structures of monomers and polymers were confirmed by 1 H NMR, FTIR, and elemental analysis. Such polymers with high physical−chemical stability and comparable BET surface areas can uptake 1.44 wt % H 2 at 77 K/1 bar and 14.0 wt % CO 2 at 273 K/1 bar and present a high selectivity for gas adsorption of CO 2 (CO 2 /N 2 ideal selectivity up to 45 at 273K/1.0 bar). The nitrogen-and oxygen-rich characteristics of carbazole and dibenzofuran feature the networks strong affinity for CO 2 and thereby high CO 2 adsorption capacity. This also helps to thoroughly understand the influence of pore structure and chemical composition on the adsorption properties of small gas molecules.

Three silicon and nitrogen-centered cyanate monomers tetrakis(4-cyanatophenyl)silane, tetrakis(4-cyanatobiphenyl)silane, and tris(4-cyanatobiphenyl)amine were designed and synthesized, which were then polymerized via thermal cyclotrimerization reaction to create highly porous cyanate resin networks with systematically varied nodes and linking struts. The chemical structures of monomers and polymers were confirmed by 1 H NMR, FTIR, solid-state 13 C CP/MAS NMR spectra, and elemental analysis. The products are amorphous with 5% weight-loss temperatures over 428 °C. The results based on N 2 and CO 2 adsorption isotherms show that the pores in these polymers mainly locate in the microporous region, and the BET surface areas are up to 960 m 2 g −1 , which is the highest value for the porous cyanate resin reported to date. The nitrogen-and oxygen-rich characteristics of cyanate resins lead to the networks strong affinity for CO 2 and thereby high CO 2 adsorption capacity of 11.1 wt % at 273 K and 1.0 bar. The adsorption behaviors of H 2 , CO 2 , benzene, n-hexane, and water vapors were investigated by correlating with the chemical composition and porosity parameters of the networks as well as the physicochemical nature of adsorbates.

New classes of nanoporous organic polymers based on 1,3,5-triazine units (NOP-1-6) were synthesized via a straightforward, methane-sulfonic acid-catalysed, cost-effective Friedel-Crafts reaction of 2,4,6trichloro-1,3,5-triazine and tetrahedral building blocks. Among them, NOP-3 with a Brunauer-Emmet-Teller (BET) specific surface area up to 894 m 2 g À1 and the total volume exceeding 0.41 m 3 g À1 exhibits good hydrogen adsorption capacity (up to 1.14 wt% at 77 K/1.0 bar) and high carbon dioxide uptake (up to 11.03 wt% at 273 K/1.0 bar). Furthermore, it presents an effective selectivity for CO 2 adsorption (NOP-6, CO 2 /N 2 selectivity 38.7 at 273 K/1.0 bar), demonstrating potential applications in gas adsorption and separation.

Microporous polyimide networks with BET surface areas up to 1407 m(2) g(-1) and pore size distribution of 4-8 Å were synthesized. The respective effect of surface area and affinity between hydrogen molecule and polyimides on hydrogen storage properties were investigated.

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