Nitrophenols (NPs) are widely used in industries and highly toxic to ecological environment and human health. Because aminophenols (APs) are important chemicals, catalytic reduction of NPs via efficient and environment-friendly strategies is of great importance. Herein, we developed a green photocatalysis route to efficiently convert NPs to APs using a Fe (II) modified graphitic carbon nitride (g-C 3 N 4 ) photocatalyst, where phenanthroline units were employed to bridge Fe (II) and carbon nitride framework. The optimized sample P-CN-8-Fe presented significantly improved absorption of visible light, separation of photogenerated charges and carrier transportation in comparison with the pristine g-C 3 N 4 and the modified samples of CN-Fe and P-CN-8. Accordingly, the P-CN-8-Fe showed a high conversion (97%) of p -nitrophenol ( p -NP) to p -aminophenol ( p -AP) under 2 h visible light irradiation, and meanwhile possessed high photocatalytic durability. Its high activity was also demonstrated through photocatalytic reduction of other NPs and nitrobenzene compounds. Finally, a possible mechanism was proposed for the photocatalytic reduction of p -NP by P-CN-8-Fe. This work provides an effective approach to prepare Fe (II) modified g-C 3 N 4 through the bridging effect of phenanthroline group, which is a potential visible light driven photocatalyst for reduction of nitrobenzene derivatives.
Yuda Zhu,Nini Xin,Zi Qiao,Suping Chen,lingwan Zeng,Yusheng Zhang,Dan Wei,Jing Sun,Hongsong Fan
Traditional tumor treatments suffer from severe side effects on account of their invasive process and inefficient outcomes. Featuring a unique physical microenvironment, the tumor microenvironment (TME) provides a new research direction for designing more efficient and safer treatment paradigms. In this study, we fabricated a polydopamine (PDA)-based TME-responsive nanosystem, which successfully integrates glucose degradation, the Fenton reaction, and photothermal therapy for efficient cancer therapy. Through a convenient hydrothermal method, Fe2+-doped Fe(II)–PDA nanoparticles were successfully fabricated, which show an excellent photothermal effect and interesting reactivity for the Fenton reaction. Instead of introducing toxic anticancer agents, natural glucose oxidase (GOD) was grafted on Fe(II)–PDA, forming a cascade catalytic nanomedicine for a specific response to the glucose in TME. GOD grafted on Fe(II)–PDA–GOD is ought to catalyze abundant glucose in TME into gluconic acid and H2O2. The concomitant generation of H2O2 can enhance the efficiency of the sequential Fenton reaction, producing abundant hydroxyl radicals (•OH) for cancer therapy. Besides, the overconsumption of intratumoral glucose also could inhibit tumor growth by reducing the energy supply. Taken together, the in vitro and in vivo antitumor studies of such TME-based Fe(II)–PDA–GOD nanosystems displayed a favorable synergistic potency of glucose degradation, the Fenton reaction, and photothermal therapy against tumor growth. Our design expands the biological application of multifunctional PDA while providing novel strategies toward effective antitumor treatment with minimal side effects.