The accumulation of non-degradable plastic waste presents a critical environmental challenge, necessitating the development of energy-efficient, and sustainable recycling methodologies. Conventional thermal catalytic processes often entail high energy inputs and limited selectivity, while photocatalytic approaches suffer from low quantum yields. Photothermal catalysis has emerged as a synergistic strategy that harnesses broadband solar irradiation to generate localized thermal gradients and active charge carriers, thereby enabling efficient chemical upcycling of polymeric substrates under mild operational conditions. This review comprehensively examines recent advances in photothermal catalysis for plastic valorization, with emphasis on mechanistic understanding, photo-thermal material classification, and structural design principles. Plasmonic metals (e.g., Au, Ag, Ru), defective semiconductors (e.g., oxygen-deficient TiO₂, doped g-C₃N₄), and carbon-based nanostructures (e.g., graphene, carbon nanotubes) are analyzed in terms of their light-to-heat conversion efficiency and catalytic functionality. We further summarize engineering strategies for enhanced photon utilization and reaction kinetics, including defect modulation and heterojunction formation, evaluate critical aspects from reactor design to scalability, address key challenges of stability and feasibility, and propose future directions such as machine learning-assisted catalyst discovery. This work aims to provide a foundational framework for the development of solar-driven plastic upcycling technologies aligned with circular economy objectives.

Epoxy resin (EP) is a widely utilized thermosetting resin in structural and functional materials; however, achieving a delicate balance between flame retardancy and stress-sensitive properties remains a significant challenge. Herein, a multifunctional flame-retardant strategy was rationally designed by incorporating polyphosphazene-decorated hierarchical nickel phyllosilicate (NiPS@PZN) as a reinforcing and wear-resistant filler while 9,10-dihydro-9-oxa-10-phospaphenanthrene-10-oxide (DOPO) as a flame-retardant synergist. Results demonstrate that the synergistic incorporation of NiPS@PZN and DOPO (1:1 mass ratio) at a total loading of 6% endows the EP composites with a UL-94 V-0 rating and elevates the limited oxygen index to 26.6%. This hybrid system also suppresses the total heat release, total smoke production, and carbon dioxide production by 10.4%, 23.2%, and 26.8%, respectively. The formation of a continuous and dense char layer confirms a dual-phase flame-retardant mechanism involving both condensed and gaseous phases. Moreover, the synergistic effect of NiPS@PZN and DOPO facilitates the concurrent optimization of mechanical and tribological properties, remarkably increasing the tensile strength to 103.5 MPa and achieving a minimum wear rate of 1.78 × 10⁻⁵ mm³·N^–1·m^–1. This study offers a viable pathway for the rational design of multifunctional additives and the fabrication of high-performance composites.

Liquid organic hydrogen carriers (LOHCs) represent a highly promising strategy for hydrogen storage and long-distance transport, offering a safe and economically viable solution to key infrastructure challenges. The effective application of LOHCs requires dehydrogenation catalysts that strike an optimal balance between activity and stability. Herein, we report a precisely engineered CoO_x-modified Pt/Al₂O₃ catalytic system that exhibits outstanding performance in the dehydrogenation of perhydro-dibenzyltoluene (H18-DBT). Systematic investigations identify a critical CoO_x loading threshold at 1 wt%, at which the catalyst achieves a maximum dehydrogenation degree (DoD) of 93% and a H₂ production rate of 20.98 × 10³ {\mathrm{m}\mathrm{o}\mathrm{l}}_{{\mathrm{H}}_2}∙mol_Pt^–1∙h^–1 at 300 °C for dehydrogenation, outperforming all the catalysts reported in the literature. However, increasing the Co loading from 1 to 10 wt% results in a sharp decline in DoD from 93% to 7.2%. With the increasing CoO_x content, the cobalt species initially form amorphous CoO clusters, which subsequently transform into crystalline Co₃O₄. The amorphous CoO is found to be the key species responsible for enhanced dehydrogenation activity by increasing the electron density and reducing the particle size of Pt, thereby promoting dehydrogenation while suppressing the hydrogenation capability.

Prioritizing chemical upcycling of plastic wastes into useful chemicals can minimize the carbon footprint of petrochemical products and alleviate plastic-related pollution, but this process often encounters non-selective deconstruction that limits its scalability. This article discusses how the polystyrene waste valorization constitutes one of the cornerstones for producing valuable chemicals to advance carbon circulation, where the selective C−C bond cleavage can serve as a robust tool.

Plasma degradation of organic pollutants serves as a promising alternative to conventional water treatment methods. This study develops a dielectric barrier discharge microfluidic plasma system that synergizes microfluidic technology with plasma to achieve the continuous and efficient degradation of methylene blue. Systematic investigation of processing parameters revealed that methylene blue degradation efficiency is enhanced by increasing the residence time or plasma power, or by decreasing the initial methylene blue concentration. Notably, complete degradation (100%) of a 100 mg∙L^–1 methylene blue solution was achieved at a residence time of merely 15.95 s and a plasma power of 17.3 W. Kinetic analysis revealed that degradation process follows a pseudo-first-order reaction model. Radical quenching experiments identified hydroxyl radicals as the pivotal oxidative species driving the reaction. On this basis, reaction mechanisms as well as the scale-up strategy of the plasma-driven methylene blue degradation process were discussed. Energy yield is further used to evaluate energy efficiency of the microfluidic plasma system, highlighting its potential for practical applications. This work establishes microfluidic plasma processing as an intensified, efficient, and continuous strategy for the treatment of organic pollutants in water.

Traditional reactive dyeing of cotton requires alkali, leading to issues such as dye hydrolysis and challenges in one-bath dyeing of polyester/cotton blends with disperse dyes. To overcome these limitations, a novel acidic cross-linking strategy was developed using silicon-containing reactive dyes and the silane coupling agent (3-aminopropyltriethoxysilane, KH550). Under weak acidic conditions (pH = 5.0), a three-dimensional “dye-crosslinker-fabric” cross-linking network was successfully constructed through reactions between silanol groups and fabric hydroxyl groups, reactions between the amino groups of KH550 and the reactive groups of the dyes, and self-condensation of silanol groups, thereby fixing the dyes onto the fabrics. This method achieved high fixation rates of 91.3%–96.4%, with excellent wash and rubbing fastness. Furthermore, by selecting matching disperse dyes, one-bath one-step dyeing of polyester/cotton was realized. The thermosol process for disperse dyes did not hinder reactive dye fixation, and KH550 even enhanced disperse dye uptake. Total dye utilization exceeded 90%, with outstanding fastness and levelness. This approach shortens the dyeing process, reduces energy use and effluent load, offering an efficient and eco-friendly alternative for blended fabric dyeing.