Xun Song

Photoinduced electron transfer of poly(o-phenylenediamine)–Rhodamine B copolymer dots: application in ultrasensitive detection of nitrite in vivo

We demonstrate a new semiconducting polymer dot: the poly(o-phenylenediamine)–Rhodamine B copolymer dot (Pp–RhB dot), which emits in the red wavelength range. The Pp–RhB dots can be used as an ultrasensitive fluorescence probe for NO2−in vivo and show high selectivity and ultrasensitivity (detection limit: 2.0 × 10−11 M) for NO2−. The fluorescence of Pp–RhB dots is decreased (φ = 0.014) as a result of fast photoinduced electron transfer (PET) between the modulator (poly(o-phenylenediamine)) and the transducer (RhB), but the N–NO2 bonding mode prevents PET, causing the fluorescence emission to be enhanced (φ = 0.92). This probe effectively avoids the influence of auto-fluorescence in biological systems and gave positive results when tested in both aqueous solution and living cells.

Ultra-flyweight hydrophobic poly(m-phenylenediamine) aerogel with micro-spherical shell structures as a high-performance selective adsorbent for oil contamination

In this paper, ultra-flyweight hydrophobic poly(m-phenylenediamine) aerogel (PmPDA) was fabricated via a simple two step approach from a poly(m-phenylenediamine) micro-spherical shell (PmPDMS). The PmPDA was first formed by freeze-drying and then cross-linked via the oxidative polymerization of surface groups following an annealing process. The PmPDA is hydrophilic before the annealing process and becomes hydrophobic (the contact angle is 103.7°) after it is annealed in air. Moreover, the obtained ultra-flyweight PmPDA (ρ = 0.8 mg cm−3) has a large surface area (338 m2 g−1), low thermal conductivity (0.0125 W m−1 K−1 at 25 °C) and excellent mechanical properties. Finally, the regenerated aerogels retain their original shape and ultrahigh absorption capability after more than 10 cycles, making PmPDA an ideal candidate for practical application in the absorption or removal of organics, particularly in environmental protection and pollution control.

Theoretical calculation based synthesis of a poly(p-phenylenediamine)–Fe3O4 composite: a magnetically recyclable photocatalyst with high selectivity for acid dyes

A magnetically recyclable and highly photocatalytic poly(p-phenylenediamine)–Fe3O4 (PpPD–Fe3O4) composite photocatalyst was synthesised by a one-step chemical oxidation polymerisation based on theoretical calculation results. The band gap and selectivity of PpPD for acid dyes were studied by theoretical calculations. The calculation results showed that the PpPD molecules exhibited better conjugacy than PANI and that the band gap was more fit for use as a photocatalyst. The photocatalytic activities were evaluated by the degradation of various dyes. The stability and high selectivity of this composite was remarkable. The combination of Fe3O4 with PpPD lead to high photocatalytic activity in the degradation of the dyes under both ultraviolet, and visible light, irradiation, although Fe3O4 alone was inactive as a visible-light-driven photocatalyst.