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1. Sustainable co-production of porous graphitic carbon and synthesis gas from biomass resources

   https://doi.org/10.1038/s44296-024-00020-0  

   Pusarapu, Vishnu; Narayana_Sarma, Rakesh; Ochonma, Prince; Gadikota, Greeshma (December 2024, npj Materials Sustainability)

   Abstract Existing pathways to produce graphite which include extraction of natural graphite impact the environment, while the conversion of fossil-driven carbon to graphite around temperatures as high as 3000 °C consumes large quantities of energy. Potassium - catalyzed graphitization is a more sustainable route and can achieve graphitic carbon formation at temperatures lower than 1000 °C, while enhancing pore formation and creating porous graphitic carbon (PGC). This two-step approach involves carbonization followed by graphitization. However, the compositions of the gaseous products have not been reported in prior studies. In this perspective, the chemical transformations underlying Alkaline Thermal Graphitization (ATG) for the co-production of synthesis gas (H₂and CO) and PGC in a single step, utilizing lignocellulosic biomass, are reported. The presence of graphitic and porous carbon structures in PGC are well suited for supercapacitor applications. This promising approach maximizes resource recovery by upgrading volatile matter to synthesis gas and low value biomass residues to porous graphitic carbon (PGC), thus co-producing sustainable fuels and energy storage materials, while lowering CO₂emissions compared to existing pathways to produce graphite. 

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2. Improved Graphitization of Lignin by Templating Using Graphene Oxide Additives

   https://doi.org/10.1021/acsabm.4c01122  

   Ike, Sandra N; Vander_Wal, Randy L (December 2024, ACS Applied Bio Materials)

   Techniques to improve the graphitization of lignin, the second most abundant natural polymer, are in great demand as a viable means to obtain cost- effective and less energy-intensive graphite for various applications. In this work, we report the effects of two-dimensional nanomaterials, graphene oxide (GO) and its derivative, reduced graphene oxide (RGO), used as templating agents for the graphitization of alkali-derived lignin. The hypothesis is that during heat temperature treatment, the GO additives act as a template that allows the lignin matrix to align on its basal planes through π−π interactions. In addition, possible chemical bonding between the GO additives and lignin may extend the two planar frameworks. Results from X-ray diffraction and Raman spectroscopy showed improved graphitic quality in the lignin-GO and lignin-RGO samples compared to pure lignin at 2500 °C. Transmission electron microscopy images and selected area electron diffraction patterns also revealed ordered nanostructures and defined polycrystalline patterns in the lignin-GO and lignin-RGO samples. This work presents a method to synthesize graphitic-like materials using carbon-based templates with the advantage that there is no need for further purification of the final material as in the case of transition metal catalysts. 

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3. Carbon Foam/CaCl ₂ ·6H ₂ O Composite as a Phase-Change Material for Thermal Energy Storage

   https://doi.org/10.1021/acs.energyfuels.3c01275  

   Jing, Yikang; Dixit, Kunal; Schiffres, Scott N; Liu, Hao (July 2023, Energy & Fuels)

   Inorganic salt hydrates are promising phase-change materials (PCMs) for thermal energy storage due to their high latent heat of fusion. However, their practical application is often limited by their unstable form, dehydration, large supercooling, and low thermal conductivity. Porous melamine foam and its carbonized derivatives are potential supporting porous materials to encapsulate inorganic salt hydrate PCMs to address these problems. This work investigates the effect of pyrolysis temperature on the morphology and structure of the carbonized foams and their thermal energy storage performance. Pyrolysis of melamine foam at 700−900 °C leads to the formation of crystalline sodium cyanate and sodium carbonate particles on the foam skeleton surface, which allows the spontaneous impregnation of the carbon foam with molten CaCl2·6H2O.The form-stable foam-CaCl2·6H2O composite effectively suppresses supercooling and dehydration, demonstrating the efficacy of carbon foam as a promising supporting material for inorganic salt hydrate PCMs. 

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4. Infrared photodetection using narrow bandgap conjugated polymers

   https://doi.org/10.1117/12.3000525  

   Azoulay, Jason D (March 2024, Proceedings SPIE)

   Rau, Ileana; Sugihara, Okihiro; Shensky, William M (Ed.)

   Low-energy, infrared (IR) photodetection forms the foundation for industrial, scientific, energy, medical, and defense applications. State-of-the-art technologies suffer from limited modularity, intrinsic fragility, high-power consumption, require cooling, and are largely incompatible with integrated circuit technologies. Conjugated polymers offer low-cost and scalable fabrication, solution processability, room temperature operation, and other attributes that are not available using current technologies. Here, we demonstrate new materials and device paradigms that enable an understanding of emergent light-matter interactions and optical to electrical transduction of IR light. Photodiodes show a response to 2.0 μm, while photoconductors respond across the near- to long-wave infrared (1–14 µm). Fundamental investigations of polymer and device physics have resulted in improving performance to levels now matching commercial inorganic detectors. This is the longest wavelength light detected for organic materials and the performance exceeds graphene at longer wavelengths. Photoconductors outperform their inorganic counterparts and operate at room temperature with higher response speeds. 

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5. In Situ Transmission Electron Microscopy of Sequentially Formed FeCoNi Medium‐Entropy Nanoparticles Driving Catalytic Graphitization

   https://doi.org/10.1002/sstr.202500809  

   Ghorbani, Alireza; Yurkiv, Vitaliy; Hajilou, Narjess; Shahbazian‐Yassar, Reza (March 2026, Small Structures)

   Metal‐catalyzed graphitization offers a low‐temperature route to crystalline carbon, yet the formation pathways of active catalysts on polymer‐derived carbons remain unclear. We utilized in situ heating scanning transmission electron microscopy to track the conversion of electrospun polyacrylonitrile nanofibers doped with cobalt acetate, nickel acetate, and iron chloride into medium‐entropy FeCoNi nanoparticles that catalyze graphitization. Scanning transmission electron microscopy imaging and chemical mapping reveal a sequential reduction and formation wherein Ni nuclei appear at approximately 300°C, alloy with Co between 400°C and 500°C to form CoNi particles, and incorporate Fe at 700°C–800°C to yield medium‐entropy FeCoNi nanoparticles. Density functional theory and ab initio molecular dynamics reproduce this order by showing facile ligand pyrolysis and rapid reduction for Ni and Co precursors, whereas FeCl₃forms refractory oxide intermediates that reduce only at higher temperatures. Ab initio molecular dynamics reveals that smaller FeCoNi clusters exhibit lower thermal stability, becoming mobile at reduced temperatures. Electron diffraction and high‐resolution imaging reveal two graphitization pathways that operate in sequence: dissolution–precipitation at lower temperatures, followed by carbide formation and decomposition at higher temperatures, consistent with Fe₃C‐like signatures near 700°C. Raman spectroscopy further reveals that FeCoNi nanoparticles exhibit higher structural graphite order and fewer defects than single‐metal nanoparticle samples, leading to enhanced catalytic performance. 

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