Recent advances in photocatalytic plastic waste conversion: a review on renewable energy pathways

2.1 Fundamentals of photoreforming

2.2 Plastic feedstocks in photoreforming

2.3 Reaction intermediates and by-products

During the photoreforming process of PP and other polymeric substrates, a variety of low-molecular-weight oxidation products are produced as intermediates. Essential compounds, including formic acid (HCOOH), acetic acid (CH₃COOH), and propionic acid (CH₃CH₂COOH), are generated through the sequential degradation of polymer chains. This process is initiated by reactive oxygen species (ROS), such as hydroxyl radicals and superoxide anions. ¹⁹ Typically, these intermediates are detected in concentrations ranging from 50 to 200 μmol L⁻¹ after 6–8 h of continuous solar irradiation, with specific levels contingent upon the type of catalyst employed, the light intensity, and the characteristics of the polymer feedstock. ²⁰

Significantly, numerous products produced during this process facilitate secondary reactions that promote hydrogen evolution. For example, acetic acid, a significant intermediate resulting from the degradation of PP, can participate in photocatalytic oxidation on brookite TiO₂ surfaces, yielding as much as 2 mol of H₂ per mole of substrate. This dual functionality as both a degradation byproduct and a sacrificial agent enhances hydrogen production and overall system efficiency. Moreover, the co-processing of PP with oxygen-rich, biodegradable polymers such as polylactic acid (PLA) markedly increases the generation of intermediates. The incorporation of PLA enhances hydrophilicity, improves aqueous dispersion, and accelerates the conversion into carboxylic acids and alcohols, thereby synergistically advancing the efficacy of photoreforming.

Table 1 presents a comparative assessment of hydrogen yields across a range of plastic feedstocks employing various photocatalytic systems and light sources. Remarkably, the combination of HPT-pretreated PP with brookite TiO₂ under simulated solar conditions resulted in the highest recorded hydrogen evolution at 580 μmol h⁻¹ g⁻¹, which was further augmented to 620 μmol h⁻¹ g⁻¹ with the addition of PLA and graphene. Conversely, hydrophobic and inert plastics such as polyethylene (PE) and PS demonstrated significantly lower yields (210 and 160 μmol h⁻¹ g⁻¹, respectively). These findings underscore the pivotal role of surface modification, photocatalyst design, and composite engineering in facilitating the efficient solar-driven upcycling of plastics. Faradaic efficiency, which exceeded 45 % in certain instances, was calculated by determining the ratio of actual H₂ evolved (measured via gas chromatography) to the theoretical electron equivalents associated with substrate oxidation, with product analysis corroborating the electron-to-product correspondence.

3.1 Comparison with anatase and rutile

3.2 Synthesis and characterization techniques

4.1 Principles of SPD and HPT

SPD encompasses a category of metalworking methodologies that exert extraordinarily high shear strains to refine the grain structures of materials to sub-micrometer or nanometer dimensions. Among the various SPD techniques, HPT is regarded as one of the most efficacious methods for achieving ultrafine grain refinement. The HPT process involves compressing a disc-shaped specimen between two anvils under pressures typically ranging from 6 to 10 GPa while concurrently implementing rotational shear. The resultant induced shear strain frequently surpasses γ > 1,000 %, facilitating substantial plastic deformation without altering the overall dimensions of the specimen. This procedure culminates in elevated dislocation densities, refined grain sizes (∼50–200 nm), and modified phase boundaries, which collectively enhance chemical reactivity and surface energy.

Although HPT has been extensively utilized within metallic systems to enhance attributes such as hardness, corrosion resistance, and catalytic activity, it is now being innovatively adapted for polymers and semiconductor materials. In the context of polymers, such as PP, HPT engenders chain scission, molecular alignment, and amorphization, thereby generating a disordered structure that enhances wettability and catalyst interaction. This unconventional application signifies a paradigm shift from merely augmenting mechanical performance to facilitating chemical and catalytic functionalities.

4.2 Integration of HPT in photocatalysis

The integration of HPT into photocatalytic frameworks presents an innovative approach for enhancing polymer–catalyst interfaces and improving catalytic performance. In heterogeneous solid-state systems comprising PP and TiO₂, HPT catalyzes micro- and nano-scale morphological alterations through the induction of polymer chain scission and the generation of amorphous domains. These structural alterations substantially elevate the hydrophilicity of PP surfaces, resulting in a reduction of water contact angles by approximately 30–40 %, which subsequently facilitates improved catalyst adhesion and slurry stability. ⁴⁰

Regarding the catalyst component, HPT engenders significant surface defects in brookite TiO₂, including oxygen vacancies, lattice distortions, and the emergence of Ti³⁺ centers. These defect sites enhance light absorption, diminish electron–hole recombination, and accelerate interfacial charge transfer. For instance, a study conducted by Chen et al. documented a 1.8-fold augmentation in photo-induced current and a 2.4-fold increase in hydrogen evolution, achieving 580 μmol h⁻¹ g⁻¹ under UV-visible illumination. ^{41 , 42}

BET surface area assessments indicated a notable amplification from approximately 100 m²/g to around 160 m²/g following HPT treatment, signifying a 60 % enhancement. This augmentation, coupled with an expanded interfacial area (by as much as 80 %), promotes enhanced light penetration and reactant diffusion. These findings corroborate the interaction between mechanical deformation and photocatalytic efficacy in waste-to-energy conversion. ⁴³

Table 3 presents an exhaustive examination of the processing parameters and microstructural alterations induced by HPT, highlighting its significant contribution to enhancing the efficacy of polymer–photocatalyst systems. The application of pressures within the range of 6–10 GPa, along with shear strains exceeding 1,000 %, results in substantial grain refinement (50–200 nm), defect proliferation, and the amorphization of the polymer matrix. Such modifications result in a remarkable enhancement of hydrogen yields by as much as 2.4 times, a reduction in contact angles by 30–40 %, and an increase in surface area by 40–60 %, thereby facilitating improvements in wettability, catalyst anchoring, and light absorption. Importantly, the density of Ti³⁺ defects escalates by a factor of 1.5–2, thereby promoting the generation of ROS and augmenting the overall photocatalytic performance. Additionally, HPT amplifies the TiO₂–PP interfacial area by 50–80 %, which fosters more efficient charge transfer pathways. With processing durations as brief as 5–30 min per disc, HPT positions itself as a time-efficient and high-throughput alternative to conventional chemical modification methods. These synergistic effects underscore the transformative potential of HPT as a pre-treatment strategy for advancing technologies that utilize solar energy for plastic waste conversion.

5.1 Strain-induced defect chemistry

HPT processing engenders extensive structural imperfections within both TiO₂ photocatalysts and polymer substrates, which significantly enhance photocatalytic efficacy. In brookite TiO₂, the application of torsional stress engenders oxygen vacancies and Ti³⁺ centers through the distortion of the TiO₆ octahedra, effectively diminishing the bandgap and broadening the light absorption spectrum into the visible range. These imperfections serve as active sites for electron entrapment, thereby mitigating recombination and promoting prolonged charge separation. Concurrently, on the polymer side, HPT initiates mechanochemical oxidation, culminating in the formation of carbonyl and carboxyl functional groups, particularly in PP. Such functional groups augment wettability and facilitate interfacial bonding with the catalyst. Spectroscopic evaluations, including PL and electron paramagnetic resonance (EPR), confirm a significant reduction in recombination rates and an increase in defect density following HPT treatment. ⁵³ For instance, EPR signals corresponding to Ti³⁺ sites exhibit a 40–60 % increase, while the PL intensity demonstrates a concomitant decline, indicating more efficient charge utilization. Collectively, these strain-induced alterations enhance light absorption, surface reactivity, and catalytic longevity within the photoreforming paradigm. ⁵⁴

Figure 1 elucidates the mechanisms underlying charge transfer and the generation of ROS within the brookite TiO₂ system subjected to HPT. The HPT process facilitates the formation of oxygen vacancies and Ti³⁺ centers by distorting the TiO₆ octahedral framework, thereby enhancing the material’s ability to absorb light and reducing the likelihood of electron-hole recombination. Upon exposure to light irradiation, electrons become excited and transition to the conduction band, facilitating the reduction of protons and leading to the production of hydrogen. At the same time, the holes engage in the oxidation of water or reactive intermediates, culminating in the generation of ROS such as hydroxyl radicals (·OH) and superoxide anions (O₂⁻·). These ROS play a pivotal role in the degradation of PP polymer chains, resulting in the formation of low-molecular-weight byproducts, including formic and acetic acids. The defects induced by the HPT treatment substantially enhance the efficiency of charge separation, catalytic activity, and ultimately, the total hydrogen yield during the photoreforming of plastic materials.

Figure 1:

Charge transfer and ROS generation in HPT-TiO₂ system.

5.2 Catalyst–plastic interfacial coupling

The HPT methodology mechanically amalgamates TiO₂ nanoparticles into the softened, amorphous structure of PP, creating intimate and stable interfaces that are essential for efficient charge transfer. These interfaces expedite the rapid migration of photogenerated charge carriers across the catalyst–polymer interface, thereby facilitating localized redox reactions. Electrons residing in the TiO₂ conduction band reduce water to hydrogen, whilst holes oxidize PP fragments or their functionalized derivatives, yielding low-molecular-weight organics. ⁵⁵ The enhanced interfacial coupling further enables a self-sustaining reaction cycle in which intermediate products, such as formic acid and acetic acid, synthesized in situ, serve as sacrificial agents, donating electrons and thereby expediting hydrogen evolution. EIS reveals a pronounced reduction in charge transfer resistance (Rct) of 35–50 % in HPT-treated composites compared to their untreated counterparts, underscoring improved charge mobility. This interfacial synergy also undergirds more stable and prolonged operation under continuous irradiation, effectively addressing one of the principal limitations inherent in traditional photoreforming systems. ⁵⁶

Table 4 outlines the primary organic intermediates formed during the photocatalytic degradation of various plastic feedstocks and explains their role in promoting hydrogen evolution. Among these intermediates, formic acid and acetic acid emerge as the most significant, exhibiting concentrations that span from 80–200 μmol L⁻¹ and 50–180 μmol L⁻¹, respectively, with faradaic efficiencies surpassing 45 %. These intermediates function as electron donors and sacrificial agents, playing a crucial role in photooxidation reactions that yield hydrogen gas. Additionally, compounds such as ethanol, methanol, and lactic acid contribute to the stabilization of charge carriers, thereby augmenting the overall hydrogen yield through enhanced electron availability. In contrast, entities such as terephthalic acid and benzaldehyde exhibit relative inertness or minimal contribution to H₂ evolution, often necessitating supplementary oxidation processes. The data further indicate that mixed polymer systems (e.g., PP + PLA) generate a more extensive array of intermediates that collaboratively enhance hydrogen evolution. The presence and dynamics of these compounds highlight the bifunctional aspect of photoreforming: not only does it facilitate the degradation of plastics, but it also generates value-added hydrogen and chemicals.

5.3 Experimental highlights

Empirical investigations have consistently demonstrated that HPT directly enhances hydrogen production efficiency in photoreforming systems, particularly as a function of increasing torsional strain. For instance, in a series of meticulously controlled experiments, the number of HPT revolutions applied to PP–TiO₂ discs was systematically increased from 1 to 10 turns, culminating in a linear escalation of hydrogen generation from 230 μmol h⁻¹ g⁻¹ to 580 μmol h⁻¹ g⁻¹ under simulated solar illumination. This increase closely correlates with the observed enhancement in microstructural defects and functional groups scanning electron microscopy (SEM) analysis elucidates the phenomena of surface roughening and crack propagation in PP, thereby promoting the entrapment of catalysts and facilitating the ingress of water. ⁶⁴ FTIR spectroscopy reveals enhanced peak intensities associated with C=O and O–H stretching vibrations, indicating the gradual chemical oxidation of the polymeric matrix. Raman spectroscopic analysis reveals peak broadening in TiO₂, indicating lattice disorder and mechanical strain. ⁶⁵ Lastly, Gas chromatography-mass spectrometry (GC-MS) analysis provides quantitative evidence of an escalation in the concentrations of formic acid and acetic acid, reaching levels of 200 μmol L⁻¹, thereby corroborating the enhanced degradation of plastic and the formation of intermediates. Collectively, these findings highlight a direct relationship between the parameters of HPT processing, structural alterations, and enhanced catalytic efficacy, thereby establishing HPT as a crucial factor in advancing photoreforming techniques for hydrogen generation from plastic waste. ^{33 , 66 , 67}

Figure 2 illustrates the correlation between the quantity of HPT rotations applied to PP and the corresponding hydrogen yield during the photoreforming process. A nearly linear relationship is discerned, with hydrogen production escalating from 230 μmol h⁻¹ g⁻¹ at one rotation to 580 μmol h⁻¹ g⁻¹ at 10 rotations. ⁶⁸ This incremental augmentation is ascribed to the heightened formation of defects, enhanced interfacial contact between TiO₂ and the polymeric matrix, as well as an expanded active surface area. The findings emphasize the criticality of mechanical strain engineering as a modifiable variable to enhance photocatalytic efficacy and hydrogen generation in systems designed to valorize plastic waste. ^{69 , 70 , 71}

Figure 2:

Hydrogen yield vs. HPT torsion turns.

6.1 Hydrogen fuel yield per gram of plastic

A pivotal parameter in assessing the feasibility of photoreforming technologies is the hydrogen fuel yield per gram of plastic. Recent investigations employing HPT-treated PP in conjunction with brookite TiO₂ photocatalysts have demonstrated hydrogen yields reaching up to 580 μmol h⁻¹ g⁻¹ under simulated solar illumination. This translates to roughly 1.16 mg of H₂ per gram of plastic per hour, provided that standard temperature and pressure (STP) conditions are maintained. ⁷³ Considering a daily irradiation cycle of 6 h, a single gram of plastic waste could potentially yield nearly 7 mg of hydrogen per day, totaling 84 mg over a 12-day cycle. Although this yield may initially appear modest, its significance escalates when extrapolated to industrial scales. Processing 1 ton of PP waste daily could generate 8.4 kg of hydrogen, sufficient to power numerous hydrogen fuel cell vehicles or supply electricity to off-grid systems. Consequently, the conversion of waste into hydrogen epitomizes a valuable repurposing of plastics, concurrently aligning with the objectives of a circular economy. ⁷⁴

6.2 Energy balance and carbon footprint reduction

The energy return on investment (EROI) and net carbon impact constitute essential factors in evaluating the sustainability of any energy conversion technology. Photoreforming functions effectively at ambient temperatures and pressures, relying solely on the input of light energy and requiring no external thermal energy, thus markedly reducing energy consumption compared to thermal depolymerization or gasification techniques. ⁷⁵

While the HPT pre-treatment phase is characterized by mechanical intensity, its energy input can be fine-tuned to below 0.5 kWh per kilogram of plastic, particularly when executed in batch or continuous processes that incorporate mechanical energy recovery. Given that hydrogen has a superior heating value of approximately 33.3 kWh/kg, even minimal production yields can result in advantageous net energy returns. ⁷⁶

Significantly, life-cycle assessment (LCA) investigations indicate that the photoreforming of 1 ton of plastic waste can counterbalance up to 3.2 tons of CO₂ equivalent emissions. This is accomplished by displacing hydrogen conventionally generated through steam methane reforming (SMR), a process that typically emits around 9–12 kg of CO₂ per kg of H₂, and by preventing methane emissions associated with plastic disposal in landfills. ⁷⁷ Consequently, the photoreforming methodology provides dual environmental benefits: it diverts solid plastic waste from landfills and reduces GHG emissions through the production of low-carbon hydrogen.

6.3 Integration into decentralized waste-to-energy systems

The modular architecture and minimal spatial requirements of HPT-photoreforming systems make them particularly advantageous for incorporation into decentralized waste-to-energy (WtE) frameworks, especially in urban, remote, or developing areas. In contrast to centralized incineration or chemical recycling facilities, which necessitate substantial capital investment and infrastructure development, photoreforming reactors can be engineered as compact, solar-powered units suitable for community-level applications. In conjunction with mechanical HPT units, plastic-laden municipal solid waste (MSW) streams can be converted on-site into hydrogen for utilization in local fuel cells, alternative cooking gas solutions, or microgrid systems. ⁷³ For illustration, a decentralized facility that processes 500 kg of plastic waste daily could potentially generate up to 4.2 kg of H₂, sufficient to produce approximately 140 kW-hours of electricity per day through proton exchange membrane (PEM) fuel cells, adequate to supply energy for 40 rural households. Furthermore, this model eliminates the need for long-distance waste transportation and centralized processing, thereby reducing both logistics-related emissions and associated costs. As nations endeavor to achieve net-zero emission objectives and adopt circular economy paradigms, HPT-enhanced photoreforming stands as a scalable, low-carbon alternative for integrating plastic waste valorization into localized energy systems. ⁷⁸

Table 5 delineates a comparative analysis of essential sustainability metrics between HPT-enhanced photoreforming and traditional plastic waste management methodologies, including incineration and pyrolysis. The assessment incorporates carbon emissions, energy inputs, and hydrogen yields, standardized per ton of plastic waste subjected to processing. Furthermore, the table provides a qualitative evaluation of various parameters, including process conditions, emissions profiles, scalability potential, integration within a circular economy framework, and the maturity level of the technology as indicated by its Technology Readiness Level (TRL).HPT functions at relatively low temperatures (ambient to approximately 70 °C) and exhibits moderate water consumption, accompanied by negligible air pollution emissions due to its closed-loop operational design. Additionally, its capacity to recover formic and acetic acids further reinforces its alignment with circular economy paradigms. When juxtaposed with conventional methodologies, HPT also demonstrates a reduced solid residue footprint and provides enhanced scalability in modular and decentralized configurations. While incineration is regarded as a technologically mature process (TRL 9), HPT-photoreforming is progressing swiftly (TRL 4–6), positioning it as a highly promising technology for sustainable waste valorization in the near future.

7.1 Material combinations: HPT with other plastics

Despite the predominance of PP in existing literature, it is imperative to extend HPT-photoreforming methodologies to encompass other widely utilized polymers, including PE, PS, and PET. Each of these polymers possesses distinct structural and chemical characteristics. PE is notably inert and hydrophobic, PS contains aromatic structures that may generate diverse intermediates, and PET is characterized by ester linkages that facilitate hydrolysis. Subsequent research should investigate the extent to which HPT affects the morphology and chemical accessibility of these materials, as well as the implications of such alterations on photocatalytic degradation kinetics. Preliminary investigations have indicated that HPT-treated PET exhibits enhanced surface oxygen functionalities and improved compatibility with TiO₂, suggesting a potential for processing a broader range of plastic streams. Additionally, blended or multilayered plastic waste, frequently encountered in MSW, represents a practical yet under-researched feedstock for integrated HPT–photoreforming systems. ⁸¹

7.2 Advanced catalysts: doped TiO₂ and Z-scheme heterojunctions

Enhancing photocatalytic efficiency necessitates the innovation of more sophisticated catalyst systems that extend beyond pristine brookite TiO₂. The incorporation of doping elements, such as nitrogen (N), sulfur (S), or transition metals like iron (Fe) and tungsten (W), can substantially reduce TiO₂’s bandgap, enhance visible-light absorption, and create additional active sites. Concurrently, the establishment of Z-scheme heterojunctions by combining two semiconductors with staggered band alignments can sustain robust redox potentials while promoting the separation of charge carriers. For instance, the combination of TiO₂ with g-C₃N₄ or BiVO₄ has demonstrated over a 200 % enhancement in H₂ yield in analogous photoreforming systems. The integration of such heterostructures with HPT-treated plastics may unveil new reaction pathways and extend light responsiveness. Moreover, surface plasmon-enhanced catalysts utilizing Ag or Au nanoparticles offer additional pathways for enhancing visible-light efficiency, particularly in low-intensity solar environments.

7.3 Reactor design: continuous-flow and solar-driven systems

The progression from batch-scale investigations to continuous, scalable reactor systems is critical for the practical deployment of this technology. Future reactor designs should prioritize continuous-flow photoreactors that facilitate a consistent input and output of plastic slurry and hydrogen gas, thereby enhancing process stability and scalability. Furthermore, the incorporation of solar concentrators or optical waveguides may significantly amplify solar light intensity and prolong photoreforming operations during fluctuating daylight scenarios. Innovations such as floating photocatalytic films or fluidized-bed reactor designs may further optimize light utilization and mass transfer. These advancements must be assessed not solely for hydrogen production efficiency but also for maintenance simplicity, catalyst recovery, and compatibility with HPT-treated feedstocks. ⁸²

7.4 Machine learning: AI-driven optimization of HPT and photoreforming

The intricate parameter landscape that regulates both HPT and photoreforming encompassing factors such as pressure, torsion velocity, catalyst loading, light intensity, and reaction duration constitutes an exemplary application for the deployment of machine learning (ML) and artificial intelligence (AI) methodologies. Predictive algorithms that are meticulously trained on empirical datasets possess the capability to discern optimal process parameters, thereby maximizing hydrogen output, minimizing energy expenditure, and regulating the formation of intermediates. Methodologies, including Gaussian Process Regression (GPR), Bayesian optimization, and neural networks, have already exhibited efficacy in the realm of materials science and could significantly expedite the development cycles associated with SPD-enabled catalysis. Furthermore, AI technologies may be employed for the real-time monitoring and regulation of reactor systems through image recognition, spectroscopic data analysis, and feedback-directed adjustments of processing parameters. ⁸³

7.5 Techno-economic analysis: lifecycle and scalability

To ascertain commercial feasibility, comprehensive techno-economic analysis (TEA) and LCA must be systematically incorporated into forthcoming research endeavors. These evaluations ought to consider the energy expenditures associated with HPT (e.g., approximately 0.3–0.5 kWh/kg of plastic), the synthesis of photocatalysts, the operation of reactors, and the purification of hydrogen. The lifecycle emissions stemming from HPT-photoreforming processes necessitate benchmarking against traditional waste treatment and hydrogen production methodologies, such as incineration or steam methane reforming. Preliminary TEA models indicate that, if appropriately scaled and integrated with cost-effective solar infrastructure, photoreforming could achieve levelized hydrogen production costs below $4/kg, thus positioning it competitively alongside green hydrogen standards. LCA findings have indicated potential GHG reductions of up to 3.2 tons CO₂-equivalent for every ton of plastic processed, making it an exceedingly appealing option for incorporation into circular economy frameworks.

7.6 Integration with circular economy: closing the loop

HPT-enhanced photoreforming possesses the potential to act as a fundamental technological component within circular economy models, facilitating not only hydrogen generation but also the recovery of valuable organic chemicals resulting from plastic degradation. Intermediates such as formic acid, acetic acid, and various short-chain carboxylic acids can be harvested and valorized as feedstocks for the chemical, pharmaceutical, or food sectors. Moreover, by synergistically linking photoreforming with waste sorting, solar energy harvesting, and fuel cell technologies, a comprehensive waste-to-energy cycle can be envisaged. Future investigative efforts should focus on decentralized circular systems, where plastic waste collected at the community level is converted into fuel and chemicals on-site, thereby eliminating the need for landfills. The establishment of policy frameworks and public-private partnerships will be pivotal in realizing these models at a significant scale. ⁸⁴

The prospective advancement of HPT-enhanced photoreforming relies on multidisciplinary collaboration spanning the fields of materials science, reactor engineering, data science, and circular economy strategy. Through coordinated initiatives across these domains, this pioneering approach holds the promise of evolving into a globally scalable solution for the valorization of plastic waste and the production of clean energy.

8.1 Key technical highlights

1. Defect Engineering: The application of HPT facilitates grain refinement within the range of 50–200 nm, generates oxygen vacancies, and creates Ti³⁺ centers, thereby augmenting visible-light absorption and mitigating charge recombination phenomena.

2. Photocatalytic Yield: The integration of brookite TiO₂ with HPT-modified PP yielded a remarkable 2.4-fold enhancement in hydrogen production, achieving levels of up to 580 μmol h⁻¹ g⁻¹.

3. Reactive Intermediates: The synthesis of organic acids at concentrations ranging from 50 to 200 μmol L⁻¹ markedly improved faradaic efficiency, surpassing 45 %.

4. Surface Enhancement: Composites treated with HPT exhibited a reduction in contact angle by 30–40 % alongside a 40–60 % increase in BET surface area, thereby facilitating improved dispersion and charge transport dynamics.

5. Material Validation: SEM, FTIR, Raman spectroscopy, and GC-MS corroborated significant morphological, chemical, and optical transformations consequent to HPT treatment.

8.2 Future outlook

The advancement of this hybrid methodology necessitates interdisciplinary research into co-doped photocatalysts, an expansion of compatible plastic feedstocks, and the incorporation of AI for real-time process control within continuous-flow reactors. Scaling the HPT-based photoreforming process within the framework of a circular economy could potentially reduce hydrogen production costs to below $4 per kilogram, while simultaneously decreasing CO₂ emissions by 3.2 tons for each ton of plastic processed. In summary, this approach presents a sustainable and highly efficient solution to the dual global challenges of plastic pollution and the generation of clean energy.