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The escalating issue of plastic waste generation has prompted the search for an effective solution to address these challenges. In this study, we present a novel plasma‐enabled strategy for the rapid breakdown of various types of plastic wastes, including mixtures, into high‐value carbon nanomaterials and hydrogen. The H2 yield and selectivity achieved through the implemented catalyst‐free plasma‐enabled strategy are 14.2 and 5.9 times higher, respectively, compared to those obtained with conventional thermal pyrolysis under similar conditions. It is noteworthy that this catalyst‐free plasma alone approach yields a significantly higher energy yield of H2 (gH2/kWh) compared to other pyrolysis processes. By coupling plasma pyrolysis with thermal catalytic process, employing of 1 wt. % M/CeO2 (M=Fe, Co, and Ni) atomically dispersed catalysts can further enhance hydrogen production. Specifically, the 1 wt. % Co/CeO2 catalyst demonstrated excellent catalytic performance throughout the 10 cycles of plastic waste decomposition, achieving the highest H2 yield of 46.7 mmol/gplastic (equivalent to 64.4 % of theoretical H2 production) and nearly 100 % hydrogen atom recovery efficiency at the 7th cycle. Notably, the H2 yield achieved over the atomically dispersed Fe on CeO2 surface (1 wt. % Fe/CeO2) in the integrated plasma‐thermal catalytic process is comparable to that obtained with Fe particles on CeO2 surface (10 wt. % Fe/CeO2). This outcome, demonstrated with single‐atom catalysts, offers a promising avenue for cost‐effective and efficient chemical plastic recycling. Through a combination of experimental and computational efforts, we have provided an in‐depth understanding of the catalytic mechanisms of the investigated single atom catalysts in the developed plasma‐enabled process. This innovative and straightforward approach provides a promising and expedient strategy for continuously converting diverse plastic waste streams, including mixed and contaminated sources, into high‐value products conducive to a circular plastic economy. [ABSTRACT FROM AUTHOR]

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H2S and CO2 are common coexisted gases widely existing in natural gas resources, and they need to be treated harmlessly. The traditional Claus treatment process only focuses on H2S treatment but ignores CO2. This article systematically conducted theoretical thermodynamic research on the thermocatalytic conversion of H2S and CO2. It was found that increasing the reaction temperature and H2S ratio would have a positive impact on the reaction, while increasing the pressure would lead to a decrease in the conversion rate of reactants and product yield, and introducing COS into the feed gas could have a promoting effect on the reaction. Furthermore, 5 %Mo/Al2O3 catalyst was used to preliminarily explore the thermal and photothermal catalysis for H2S and CO2 conversion. The results showed that the photothermal catalysis significantly promoted the production of syngas (H2 and CO), and suppressed COS production in contrast to thermal catalysis. This indicates that the introduction of light could effectively convert H2S and CO2 into high‐value product syngas, providing important reference value for further research on the conversion of H2S and CO2. [ABSTRACT FROM AUTHOR]

Under the goals to reach carbon peaking and carbon neutrality, the clean and efficient utilization of fossil fuels has become a crucial aspect of the energy transition. Methane as one of the cleanest fossil energies, has been widely regarded as a key technology with good development prospects in energy transition for high-value and clean utilization. Methane pyrolysis for hydrogen process has the advantages of producing high-purity H2 and carbon materials without directly generating CO2. Three typical methane pyrolysis for hydrogen processes: catalytic methane pyrolysis in fluidized beds, plasma methane pyrolysis, and molten medium methane pyrolysis were summarized and their principles, advantages, disadvantages and research progress were introduced. Among these processes, catalytic methane pyrolysis in fluidized beds requires the least energy but the catalysts are prone to carbon deposition, leading to unsustainable reactions and difficulty in separating carbon materials from catalysts, affecting downstream use. Plasma methane pyrolysis has a high conversion rate but requires a substantial energy input. Molten medium methane pyrolysis has lower energy consumption, and the carbon materials float on the surface of the molten medium, not hindering the continuous reaction and are easily separated and collected. However, the high temperature of the molten medium requires high requirements for the reactor materials, and the cost of purifying carbon materials also affects the economic viability of this process for industrialization. Combining renewable energy is the future trend towards achieving clean and efficient methane pyrolysis for hydrogen. Utilizing renewable energy sources such as solar and wind energy to provide the energy required for methane pyrolysis processes, can reduce the reliance on traditional energy. From current research and development trends, molten medium methane pyrolysis process for hydrogen integrated with renewable energy sources is expected to become the key process for methane pyrolysis for hydrogen and carbon materials. [ABSTRACT FROM AUTHOR]

Amidst the rapid expansion of the global economy, the demand for energy has escalated. The depletion of traditional energy sources coupled with environmental pollution concerns has catalyzed a shift towards the development and utilization of clean, renewable energy. Biogas, as a renewable energy source, provides diverse applications and holds the potential to alleviate energy shortages. Recently, biogas dry reforming technology has garnered substantial attention as a significant pathway for renewable energy utilization, particularly in the development and optimization of catalysts. Contemporary research predominantly focuses on enhancing the activity and stability of catalysts, with particular emphasis on their resistance to coking and sintering. This review delineates the classification of biogas dry reforming catalysts, their catalytic activity, and issues related to carbon deposition, contrasting biogas dry reforming with traditional dry reforming in catalyst design. It synthesizes numerous studies from recent years aimed at mitigating carbon deposition during the biogas dry reforming process and boosting catalytic activity via active components, carriers, and promoters in both precious and non-precious metal catalysts. Furthermore, it discusses the current challenges of biogas dry reforming technology and outlines prospective future development trends. This discussion provides an in-depth understanding of biogas dry reforming technology and catalyst design, offering insights and recommendations for future research and industrial applications. [ABSTRACT FROM AUTHOR]

The article in Angewandte Chemie International Edition discusses a novel plasma-enabled process using single-atom catalysts to convert unsorted plastic waste into valuable carbon materials and hydrogen. Researchers led by Guoxing Chen and Anke Weidenkaff have developed an efficient and cost-effective method to decompose mixed plastics, offering a breakthrough in sustainable waste management. This innovative approach shows promise for large-scale recycling of post-consumer plastics, addressing environmental concerns and promoting a circular economy. [Extracted from the article]

The article in Angewandte Chemie discusses a new plasma-enabled process using single-atom catalysts to convert various types of plastic waste into valuable carbon nanomaterials and hydrogen. Researchers Guoxing Chen, Zeai Huang, Ying Zhou, Anke Weidenkaff, and others have developed an efficient and cost-effective method for upcycling unsorted plastic waste, offering a promising solution for sustainable waste management and large-scale recycling of mixed post-consumer plastics. [Extracted from the article]

The selective photocatalytic reduction of CO2 by H2O to methanol is a desirable solution for solar energy storage with the production of abundant chemicals. However, this is a formidable challenge because the conversion of CO2 to CH3OH is a 6-electron transfer reaction that needs 4 protons, while other products requiring less electrons and protons, such as CO, HCOOH, and HCHO, are much easier to form than CH3OH, leading to lower selectivity for the production CH3OH. Herein, we propose a novel concept of targeting activated H2O to provide ample protons without the generation of strong oxidative free radicals for the highly selective photocatalytic reduction of CO2 to CH3OH with H2O. Carbon nitride (CN)-supported cobalt sulfide (CS) was fabricated as the desired prototype photocatalyst (CS/CN). Cobalt sulfide was confirmed to promote the generation of protons without the formation of strong oxidative free radicals (such as ˙OH and ˙O2−) by significantly weakening the overpotential of the H2O oxidation half-reaction. This targeted H2O activation contributed to the continuous coupling of multi-protons/electrons and CO2 to form the key intermediates CHO* and CH3O*, which were necessary for the generation of CH3OH. Accordingly, the CH3OH selectivity by the optimized CS/CN (87.2%) photocatalyst was 2.3 times higher than that of CN (38.6%) with an increase in the CH3OH production rate from 22.0 μmol g−1 h−1 to 97.3 μmol g−1 h−1. This work provides an elegant solution to achieve the highly selective photocatalytic conversion of CO2 to CH3OH by modulating the H2O activation process. [ABSTRACT FROM AUTHOR]

Production of peroxodisulphate (S2O82–) on powdered photocatalysts is a promising way to obtain high-value-added chemicals using solar energy; however, it is still suffering from low efficiency. In the present work, we fabricated bimetallic Au core and Pt shell nanoparticle-loaded WO3 (Au@Pt/WO3) photocatalyst for enhanced production of S2O82–, which is 1.7 times that of Pt nanoparticle-loaded WO3 (Pt/WO3), and was reported to be the best catalyst for S2O82– production. A further study demonstrated that the electronic interaction of Pt was successfully modulated by the core–shell nanoparticle architecture, and the core–shell nanoparticle structure between Au and Pt improved the formation of the surface chemical state of Pt to be metallic Pt, proposed as the active site for oxygen reduction. Besides, the core–shell nanoparticle structure also exposed a large amount of Pt on the surface of the substrate. As a result, Au@Pt/WO3 showed significantly enhanced photocatalytic activity of S2O82– with a quantum efficiency of 5.2% at 420 nm, whereas Pt–Au bimetallic alloy nanoparticle-loaded WO3 with a large amount of surface PtOx and exposed both Au and Pt on the surface showed very low activity. This work provides insights into the bimetallic Pt nanoparticle-loaded WO3 for enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]