Plastic waste as a feedstock for solar-driven H₂ generation

Abstract

Plastic waste is recycled to hydrogen using sunlight and a CdS photocatalyst.

Visible Light–Driven Cascade Carbon–Carbon Bond Scission for Organic Transformations and Plastics Recycling

“…Remarkably, after 6 days, full substrate conversion was observed, in contrast to the previously reported example for photoreforming of plastics, where a conversion of up to only 50% was reported after 18 days. [41,52] Furthermore, our system does not require alkaline pretreatment to initiate partial hydrolysis of the polymers to hasten the reaction. [41,52] We expect the reaction to proceed via cascade CC bond cleavage similar to the other macromolecular substrates that we tested, and a plausible reaction mechanism based on the observed products and our prior studies [56,57] is depicted in Figure S5 (Supporting Information).…”

“…This concept had been pioneered by Meyer and co-workers, who demonstrated its potential for chloride [25] and benzyl alcohol oxidation with simultaneous H 2 evolution. [26] Others, including Sun and co-workers, [27][28][29][30] Meyer and co-workers, [31][32][33][34][35] Berlinguette and co-workers, [36][37][38] Reisner and co-workers, [14,[39][40][41] and Lei and co-workers, [42][43][44] have subsequently shown that the gap between AP and radical catalysis can potentially be bridged via the valorization of biomass, functionalization of amines, oxidation of other halides, photo-electrochemical reduction of CO 2 , and even photoreforming of plastics.…”

“…Moreover, they only achieved conversions of about 40% for specific plastics such as polyurethane and polyethylene terephthalate, and their process, required alkaline pretreatment to partially hydrolyze the carbamate and ester linkages. [41] Though Reisner and co-workers' most recent work on the photoreforming of plastics with CN x /Ni 2 P catalysts presents an innovative advance that overcame the toxicity of their original Cd-containing photocatalysts, [52] their process still required alkaline pretreatment, while conversions remained below 50% and multiple products with modest selectivity were observed.…”

Photoreforming of biomass in metal salt hydrate solutions

“…Photoreforming (PR) allows for the simultaneous production of H 2 gas and organic products from the sunlight-driven conversion of waste polymeric substrates such as biomass and plastics in aqueous medium under ambient temperature and pressure. [1][2][3][4][5][6] TiO 2 is the archetypical photocatalyst for this process, and CdS quantum dots and carbon nitride (CN x ) have recently been reported as visible-light absorbing alternatives. [7][8][9][10][11] Efficient PR requires the substrate to easily access the photocatalyst, which poses a challenge for an insoluble polymeric substrate in combination with a heterogeneous photocatalyst.…”

Converting Thioether Waste into Organic Semiconductors by Carbon–Sulfur Bond Activation

“…Ithas been ag oal for human beings to efficiently convert organic waste into valuable materials. [1] With much effort, different technologies and methodologies have been developed to convert organic waste,such as plastic,food waste,and biomass into carbon materials, [2] fuel and energy, [3] and valuable chemicals. [4] Benzothiazole derivatives are an important organic waste in urban runoff,a nd originates from the benzothiazoles used in large volumes as vulcanization accelerators.…”