Photocatalytic materials for environmental remediation of organic pollutions and heavy metals require not only a strong visible light response and high photocatalytic performance, but also the regeneration and reuse of catalysts. In this work, a ternary hybrid structure material of Nanoscale Zero Valent Iron(Fe 0 ) doped g-C 3 N 4 /MoS 2 layered structure (GCNFM) was synthesized by a facile strategy. Compared with the pure GCN, GCNM and Fe-GCN, the photodegradation efficiency of the GCNFM toward the RhB and Cr(VI) under visible light are considerably enhanced to 98.2% for RhB and 91.4% for Cr(VI),respectively. In addition, the reaction rate constants (K RhB and K Cr ) of GCNFM are much higher than those of GCN, GCNM and Fe-GCN. attributing to that Fe 0 and MoS 2 composited with GCNM promotes the separation of photogenerated electron-hole pairs. Moreover, with the loading of MoS 2 and/or Fe 0 , the holes could displace the ·O 2as the main reactive oxygen specie in GCN. GCNFM maintains an efficient degradation ability to both the RhB and Cr(VI) after several cycles, in spite that normally Fe 0 will be consumed and deactivated with the reduction proceeding as previously reported. It suggests that the photogenerated electrons, in response, can reduce the Fe(III)/Fe(II) to Fe 0 , inducing a regeneration and reuse of Fe 0 . We anticipate this work can provide a good example for the design of efficient, visible light driven and recyclable photocatalysts for environmental remediation of both the organic pollution and heavy metals.
The development of completely recyclable polymers has become an emerging frontier in polymer chemistry; however, the efficient synthesis of monomers or/and polymers with desirable physical properties and mechanical strengths required for practical uses from renewable feedstocks under environmentally friendly conditions still represents a challenge. Herein, we report five types of completely recyclable polycarbonates made from CO 2 and biosourced epoxide featuring different substituents on the carbamate group. It is discovered that the judicious installation of various alkyl substituents can drastically enhance the thermal stability and crystalline capacity of the resultant polymers, while the stable fivemembered pyrrolidine ring can execute the complete chemical recyclability. For example, CO 2 -based polycarbonates with a t Bu substituent feature with a T g value of up to 152 °C, close to those of the BPA-based polycarbonates and i Bu-substituted CO 2 polycarbonates are thermally stable up to ∼300 °C, while Me-and Bn-substituted copolymers become crystalline. Remarkably, all of the reported CO 2 -based polycarbonates can be recycled back into the epoxide monomers in quantitative yields under mild conditions. This represents a rare example of a CO 2 -based polycarbonate featuring biosourced characteristics and unique recyclability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.