Renewable Biomass Research Articles

Engineering a Binding Peptide for Oriented Immobilization and Efficient Bioelectrocatalytic Oxygen Reduction of Multicopper Oxidases.

Enzymatic fuel cells (EFCs) are emerging as promising technologies in renewable energy and biomedical applications, utilizing enzyme catalysts to convert the chemical energy of renewable biomass into electrical energy, known for their high energy conversion efficiency and excellent biocompatibility. Currently, EFCs face challenges of poor stability and catalytic efficiency at the cathodes, necessitating solutions to enhance the oriented immobilization of multicopper oxidases for improved heterogeneous electron transfer efficiency. This study successfully identified a surface-binding peptide (SBP, 13 amino acids) derived from a methionine-rich fragment (MetRich, 53 amino acids) in E. coli CueO through semirational design. The first phase of engineering focused on the structural characteristics of MetRich, pinpointing fragment N394-H406 (SBP 1.0, corresponding to variant CueO-M12) as the key region dominating the binding. Subsequent site-saturation mutagenesis, combined with electrochemical screening, yielded three variants, and among them, the variant CueO-M12-1 (CueO-M12 H398I) exhibited a more uniform favorable orientation with a 1.38-fold increase in current density. Further electrocatalytic kinetics analysis revealed a significant 21.2-fold improvement in kinetics current density (Jk) compared with that of CueO-WT, leading to the development of SBP 2.0. When SBPs were fused to laccase from Bacillus pumilus (BpL) and fungal bilirubin oxidase from Myrothecium verrucaria (MvBOD), respectively, they transformed a sluggish adsorption process into a rapid and oriented one. In addition, compared with SBP 1.0, SBP 2.0 endows BpL and MvBOD with enhanced electrocatalytic capabilities for oxygen reduction and glucose/O2 EFC performance. The engineered SBPs are promising for serving as a versatile "glue" to enable the immobilization of oxidoreductases in an oriented manner, which leads to a breakthrough in bioelectrocatalysis and thereby overcoming the current bottleneck of EFCs.

Sustainable production of 2,5-diformylfuran via peroxymonosulfate-triggered mild catalytic oxidation of lignocellulosic biomass

Abstract The relentless depletion of fossil fuels accentuates the urgent necessity for the sustainable synthesis of chemicals from renewable biomass. 5-Hydroxymethylfurfural (HMF), extracted from lignocellulosic biomass, emerges as a beacon of hope for conversion into value-added chemicals. However, the inherent susceptibility of its unsaturated aldehyde groups to excessive oxidation often culminates in undesired reactions, compromising both the yield and specificity of the desired products. Here, we introduce a holistic methodology for the cost-effective and ecologically responsible generation of 2,5-diformylfuran (DFF), through the heterogeneously catalyzed oxidation of HMF utilizing peroxymonosulfate (PMS) under benign conditions. This strategy, characterized by the meticulous enhancement of surface ketone groups via a mixed-salt co-pyrolysis technique, achieves an unparalleled selective activation of PMS, engendering singlet oxygen to catalyze the oxidation of HMF into DFF with a selectivity surpassing 80%. Life cycle assessments underscore a negligible impact on human health, ecosystems, and natural resources, endorsing the holistic utilization of biomass. This integration of pyrolysis for the creation of functional carbonaceous materials within biomass conversion processes significantly enhances sustainability and economic viability, whilst paving new pathways for selective biomass oxidation and the production of high-value chemicals.

Renewable Energy in India: An Overview and the Path towards Sustainable Development

The utilization of natural and energy resources began to manifest in the 19th century. Throughout the 20th century, energy usage escalated significantly. Currently, around 80% of global energy consumption is derived from the extraction of fossil fuels, including oil, coal, and gas. Renewable energy has grown increasingly vital as the world confronts the issue of alleviating the adverse effects of climate change and diminishing reliance on finite and polluting fossil fuels. Utilizing renewable energy sources is acknowledged as a crucial element in advancing sustainable development, which seeks to fulfill the requirements of the current generation without jeopardizing future generations. India, akin to other developing nations, is endeavouring to implement various strategies to guarantee a cheap and accessible energy supply for its socioeconomic and political sectors in pursuit of renewable energy advancement. India's Renewable Energy Goals stipulate an objective of attaining 500 GW of installed capacity by 2030. This study aim is to examine the several sources of renewable energy, including solar, wind, hydropower, geothermal, and biomass, to facilitate sustainable development in India. Strong policy support with stable and predictable regulations, effective grid integration strategies to manage variable renewables, dedicated funding for research and development, and strong public engagement are key findings to successfully implement the state-level renewable energy. Setting aggressive renewable energy capacity installation targets, easing grid integration through transmission infrastructure expansion, and offering financial incentives like subsidies and tax benefits are significant recommendations for India to promote renewable energy.

Assessing Energy Cane Varieties for Renewable Biomass Energy: A Comprehensive Study of Economic Opportunities in the Dominican Republic

The use of vegetable biomass as a source of renewable energy is a growing trend in line with the 2030 Sustainable Development Goals approved by the United Nations in 2015. Energy cane (Saccharum officinarum) appears to be an appealing alternative for this purpose due to its high agricultural yields (150-200 ton/ha), strong resistance to common diseases compared to sugar cane, the ability to grow on marginal or less suitable lands for other commercial crops, and the feasibility of using the same labour force and machinery used for sugar production from sugar cane. Our study’s goal was the preliminary technical-economic opportunity study for an investment in a 100-hectare energy cane farm that produces energy cane bales (with 30% relative humidity) for use as fuel in biomass boilers in the Dominican Republic. The study showed that using energy cane as biomass feedstock for electricity production would result in profits from the third year onwards, making it highly financially attractive. The specific energy consumption to produce energy cane bales was 5.33 kW/t. The calculated Net Present Value was positive at US$ 128,742.50, the estimated Internal Rate of Return was 44.20%, and the payback period was just 2 years. These figures were higher than any possible bank interest rate.

Nitrogen-doped Porous Carbon Supported Nickel Catalysts for Efficient Hydrodeoxygenation of Lignin-derived Vanillin to 2-methoxy-4-methylphenol in Ethanol

Driven by the urgent global demand for clean energy, the catalytic conversion of renewable lignin biomass has attracted widespread attention. In this work, we proposed a two-step method for synthesizing nickel-supported nitrogen-doped porous carbon catalyst (Ni/NPC) for the in-situ hydrodeoxygenation (HDO) of lignin-derived vanillin (VAN) to 2-methoxy-4-methylphenol (MMP). The process involved co-hydrothermal treatment and pyrolysis of a mixture containing feedstocks and ZnCl2 activator, with simultaneous N doping and pore construction. Under optimal conditions of 0.4MPa N2 at 220 ℃ for 4h, the Ni/NPC achieved 99.13% conversion of VAN and 97.32% yield of MMP using ethanol as a hydrogen donor. The enhanced catalytic activity was attributed to the synergistic effect of Ni metal sites and N doping, and efficient pore activation of ZnCl2. In addition, the Ni/NPC maintained relatively stable activity over four cycles. This cost-effective and simple synthesis method, coupled with the high activity of the catalyst, presents a viable strategy for upgrading lignin derivatives into high-value chemicals in the H2-free HDO process.

Efficient production of spermidine from Bacillus amyloliquefaciens by enhancing synthesis pathway, blocking degradation pathway and increasing precursor supply.

Spermidine has broad application potential in food, medicine and other fields. In this study, a novel Bacillus amyloliquefaciens cell factory was constructed for production of spermidine from renewable biomass resources. Firstly, the speB gene was found to be optimal for synthesis of spermidine, and the function of SpeB was explained by amino acid sequence analysis and molecular docking. By replacing the native promoter of the speEB operon with the P43, the synthesis of spermidine was significantly enhanced in B. amyloliquefaciens HSPM1-P43speEB. After knockout of the genes yobN and bltD associated with spermidine degradation, the spermidine titer of the strain HSPM2 was further improved to 115.96mg/L, increased by 108% compared to HSPM1-P43speEB. Subsequently, the titer of spermidine was further increased to 277.47mg/L through enhancing the supply of the precursor methionine by overexpression of speD. Finally, the renewable biomass resources, xylose and feather meal were optimized to produce spermidine, and the maximum titer is up to 588.10mg/L after optimization. In conclusion, an efficient spermidine producing B. amyloliquefaciens was constructed through combinatorial metabolic engineering strategies, and the sustainable production of spermidine was achieved using the biomass resources of xylose and feather meal.

Sustainable production of cyclohexanones through hydrodeoxygenation of lignin-derived phenolics over PdFe/HZSM-5 catalysts

Despite the crucial roles of cyclohexanones across various industrial sectors, notably in the production of nylon and plastics, their conventional production heavily relies on fossil resources. The exploration of highly efficient routes to convert renewable biomass into cyclohexanones holds promise for advancing sustainable chemical processes, especially with the growing concerns in energy and the environment. Herein, we report the direct conversion of lignin-derived phenolic compounds to cyclohexanones through hydrodeoxygenation using PdFe/HZSM-5 catalysts. The successful achieved conversion of guaiacol was up to 97.27%, with a greatest selectivity of 90.59% to cyclohexanone on PdFe1.5/HZSM-5. Characterization of the catalysts further revealed that bimetallic catalyst promoted the dispersion of PdFe on HZSM-5 and facilitated the interactions between PdFe because of electron transfer, which collectively facilitated surprising outcomes. This work offers a promising strategy for improving lignin valorization within the context of producing sustainable chemicals and industrial materials.

Monomer in situ polymerization as topological sutures to achieve strong interfacial adhesion and long-term anti-mold of renewable adhesive

Integrated long-term anti-mold and high bonding capacity properties into renewable biomass adhesives hold significant importance for promoting the green and sustainable development of the wood industry, yet it remains an immense challenge. Drawing inspiration from the design of molecular suture materials, we successfully developed a series of innovative quaternary ammonium salt monomers (APM12) that polymerize in situ with glycidyl methacrylate (GMA) at the interface of bonded adherents. This process constructed molecular sutures on the molecular scale, forming a robust topological entanglement network between the adhesive and the wood substrate. Such a rational structure design allowed the modified soybean meal (SM) adhesive to present a boosted bonding strength and water resistance (2.08 and 1.05MPa). The stably riveting high-effect anti-germ platform imparted the protein adhesive with ultra-long mildew resistance of 150 days for liquid SM@GMA-APM12 adhesives, outperforming all the previously reported protein-based bio-adhesives. The implementation of the suture strategy through an in situ sutural interspersed crosslinking network provided a straightforward approach and offered a novel solution for creating renewable adhesives with multiple desirable properties. Moreover, this suture strategy can be applied to other interface strong adhesion and anti-bacterial materials comprised of polymer structure, such as hydrogel, organic coatings, and membrane, broadening its scope of applications.

Catalytic production of fused tetracyclic high-energy-density fuel with biomass-derived cyclopentanone and benzoquinone

High-energy-density (HED) fuels (e.g. JP-10) are of great importance in safeguarding territorial air security, since they can increase the flight range and payload of military aircrafts. To reduce the reliance on limited petroleum source, the production of HED fuel with renewable biomass feedstocks is highly appealing. But currently, most of the synthetic biofuels, due to their intrinsic ring structure, are incapable of competing with JP-10 in terms of energy density and freezing point. By emulating the structural characteristic of JP-10, we herein design and prepare a special C16 fused tetracyclic biofuel using renewable cyclopentanone and benzoquinone as feedstocks. Key to success depends on selective dehydration of vicinal diol (dimer of cyclopentanone) over Amberlyst-15 in [Hmim]Cl. The Amberlyst-15/[Hmim]Cl system effectively suppresses the dominant pinacol-type rearrangement pathway and also exhibits good reusability for the dehydration. The hydrogen-bonding interaction between vicinal diol and imidazolium ring, as well as electrostatic force between carbocation intermediate and chloride anion contribute to the high diene selectivity. The compact ring framework gives rise to a density of 0.966 g/mL, combustion heat of 43.1 MJ/L, freezing point of ‒67 °C, and kinematic viscosity of 12.4 cSt, which are comparable to the properties of JP-10. It is expected that this as-prepared HED biofuel may potentially serve as a renewable alternative to petroleum fuel JP-10.

One-pot chemobiological cascade strategy for synthesizing furyl hydroxymethyl ketone from corncob

Furyl hydroxymethyl ketone (FHK) is essential in synthesizing pharmaceuticals and biologically active molecules. However, green and sustainable methods for synthesizing FHK from renewable feedstocks remain challenging. This research proposed a simple one-pot chemobiocatalytic cascade strategy for effectually transforming renewable biomass into FHK via solid acid catalysis and whole-cells hydroxymethylation. Using whole-cells (SMPDC cells) containing pyruvate decarboxylase and small ubiquitin-like modifier (SUMO) fusion tag as biocatalysts, non-natural substrates furfural and formaldehyde were introduced into a C-C ligation bioreaction, establishing a biocatalytic pathway for FHK synthesis. SMPDC cells exhibited excellent biocatalytic activity and high tolerance to high furfural concentrations (up to 200mM), a well-known effective microbial inhibitor. Optimal reaction conditions were identified, enabling the manufacturing of FHK from corncob- and D-xylose-derived furfural with productivities of 0.12g FHK/(1g corncob + 0.09g HCHO) and 0.39g FHK/(1g D-xylose + 0.28g HCHO), respectively. This strategy demonstrated the potential for synthesizing valuable chemicals from low-cost biomass, providing a sustainable alternative to traditional chemical synthesis.

Synthesis of Ni-Cu/Mesoporous Silica Catalyst with Variation of TEOS and NH4OH Molar Ratio for Hydrocracking Waste Cooking Oil into Biofuel

Research on the development of sustainable and renewable energy sources has been done and intensified due to the dwindling fossil fuel reserves. Biofuels that are derived from renewable biomass sources offer a promising alternative to traditional fuels. This study focuses on the synthesis and characterization of Ni-Cu/Silica catalysts for the hydrocracking of waste cooking oil into biofuels. Mesoporous silica as supporting material was synthesized with varying TEOS/NH4OH ratios and impregnated with Ni and Cu metals to enhance catalytic activity. The synthesized catalysts were characterized using FTIR, SEM-EDX, and GSA techniques to investigate their structural and textural properties. The catalyst with a TEOS/NH4OH ratio of 1:1 exhibited the highest acidity, surface area, and catalytic activity, resulting in a 71.52% conversion of waste cooking oil into biofuel with a selectivity of 97.69% towards paraffin. These findings demonstrate the potential of Ni-Cu/Silica catalysts for the efficient production of biofuels from waste cooking oil.

Analysis of Biocharcoal Briquette Characteristics with the Addition of Trembesi (Samanea saman) Dry Leaf Bioadditives

Biocharcoal briquettes are new and renewable biomass energy products. The addition of rain tree leaf bioadaptive to biocharcoal briquettes can increase high carbon compounds. By adding these materials, it can increase the calorific value and produce better energy. The main ingredients in this study were coconut shells, corn cobs, tapioca flour, and betel leaf bioadditives. The research characteristic test was conducted to determine the levels of bound carbon, ash content, volatile matter content, calorific value, and water content. The results showed that the best composition was BBB 4 with a volatile matter content of 0.921%, water content of 2.0%, ash content of 7.9%, calorific value of 5943 cal/g, and bound carbon of 89.179%.

A 2D/3D hierarchical hybrid enables energy-saving hydrogen production coupled with glycerol and urea electro-oxidation

The design and development of high-performance electrocatalysts is crucial to improve the utility of anodic reaction for energy-saving hydrogen production. Herein, we present a novel catalyst with 2D/3D multistage structure for the electro-oxidation of renewable biomass and harmful waste to assist hydrogen generation. The hierarchical configuration of NiO/CoO nanosheets interconnected by hollow carbon spheres, leveraging both 2D and 3D advantages. This structure provides rich surface and edge active sites as well as affluent electron and mass transfer pathways, resulting in the accelerated dynamics of electro-oxidation. The hollow carbon spheres serve as a buffering agent to alleviate the strain caused by repetitive redox reactions during electrolysis, thereby bestowing exceptional structural and chemical stability for prolonged operational durability. Additionally, the multiple continuous hetero-interfaces between NiO and CoO, NiO and carbon as well as CoO and carbon can ensure the fast electron transport, leading to the expedited reaction kinetics with the synergistic effect of phase engineering between NiO, CoO and carbon shell. As a result, the 3D carbon shells jointed 2D NiO/CoO hybrids demonstrate promising catalytic activities on electro-oxidation for energy-efficient hydrogen production (∼100 %FE) coupled with urea oxidation and formic acid synthesis with excellent selectivity (95.40 %) and satisfied faradic efficiency (91.6 %).

Biomedical Potential of Cellulose: Current Trends and Future Directions

ABSTRACTThe exploration of cellulose, a natural polysaccharide derived from renewable biomass, has seen significant advancements in recent years due to its biocompatibility, biodegradability, and versatility. This review paper comprehensively covers the latest developments in cellulose and its derivatives as functional biomaterials for various biomedical applications. Emphasis is placed on the intrinsic properties of cellulose, such as its mechanical strength, thermal stability, and chemical modifiability, which enable its wide‐ranging use in drug delivery systems, wound dressings, tissue engineering, and biosensors. The article further delves into the modification techniques—such as oxidation, esterification, and etherification—that enhance cellulose's performance, allowing it to be fine‐tuned for specialized medical applications, including the creation of scaffolds for tissue regeneration and smart materials for responsive drug release. Additionally, the hybridization of cellulose with inorganic materials offers potential in developing materials with superior antimicrobial properties and improved mechanical characteristics. This review also addresses the challenges in cellulose processing, particularly concerning optimizing its structure for specific applications, while highlighting future opportunities in the field of personalized medicine and intelligent healthcare devices. By examining both the current innovations and future trends, this review highlights the growing importance of cellulose as a sustainable and versatile resource in the biomedical industry.

Advancing biorefineries with ultrasonically assisted ionic liquid-based delignification: Optimizing biomass processing for enhanced bio-based product yields

Encouraging sustainable business needs utilization of bio-based substrate for green manufacturing of chemicals and fuels to achieve sustainable development goals set by the United Nations. One of the abundantly available bio-based substrates is lignocellulosic (LC) biomass, which requires effective pretreatment to fractionate into its structural biocomponents to maximize biorefinery potential. This study addresses the use of an inexpensive ionic liquid (triethylammonium hydrogen sulfate) [T2220][HSO4] in an ultrasound-assisted process as an environmentally acceptable pretreatment method for the delignification of LC biomass, specifically rice straw (RS). Using ionic liquid (IL)-assisted (IL, acid-IL, and alkali-IL) pretreatment procedures, the effects of IL volume, sonication time, and temperature were methodically examined for RS delignification. To evaluate the compositional changes in pretreated and raw RS, instrumental analyses were carried out. The maximum rates of 47 %, 55 %, and 64 % for the only IL, acid-IL, and alkali-IL treatments demonstrated the effect of temperature, operating time, and IL concentration on the delignification efficiency. The alkali-IL pretreatment was noteworthy for achieving a 64 % delignification rate under optimum values of IL volume (8.65 mL), sonication time (123 min), and temperature (82 °C). Artificial neural networks (ANN) and response surface methodology (RSM) were used for process modeling and optimization. With an accuracy of 0.989 in correlation coefficient, the ANN model outperformed the RSM regression model regarding forecasting delignification performance. Biorefinery of renewable biomass resources ensures the sustainable supply of materials, chemicals, and fuels. The delignification and downstream product recovery technologies are major limiting factors in the commercialization of biomass processing. The suggested [T2220][HSO4]-based ultrasonic approach provides a viable way to boost biomass valorization efficiency, which in turn improves economical and sustainable biorefinery and aids in the shift to green bio-based production.

Cellulose Nanocrystal Composite Membrane Enhanced with In Situ Grown Metal-Organic Frameworks for Osmotic Energy Conversion.

Access to clean and renewable energy, osmotic energy from salinity gradient difference, for example, is central to the sustainability of human civilization. Despite numerous examples of nanofluidic membranes for osmotic energy conversion, one produced from abundant and renewable biomass resources remains largely unexplored. In this work, cotton-derived cellulose nanocrystals (CNCs) are employed to fabricate a membrane by self-assembly with polyvinyl alcohol (PVA) and subsequent in situ growth of metal-organic framework (MOF), UiO-66-(COOH)2, to provide an example. The composite membrane exhibits excellent mechanical strength and toughness due to the long chains and hydrogen bonding interactions of PVA. The incorporation of UiO-66-(COOH)2 endows the composite membrane with abundant nano- and subnano-sized ion transport channels, resulting in a 150% increase in ion conductance, while also providing superior cation selectivity through collaboration with the sulfated CNCs. The composite membrane with 27.4% MOF content can achieve an osmotic energy conversion performance of 5.10Wm-2 under a 50-fold KCl gradient condition and a monovalent cation selectivity of ≈16 for K+/Mg2+. This work presents a solution for harvesting renewable osmotic energy by constructing nanofluidic membranes using plentiful renewable biomass materials and a simple, low-emission fabrication procedure.

Optimal Solar‐Biomass‐Diesel‐Generator Hybrid Energy for Water Pumping System Considering Demand Response

ABSTRACTThe water pumping system is a vital daily operation for a sustainable society. The demand for this essential commodity is progressively growing around the world. Incorporating renewable energy sources (RES) into its operation mitigates adverse environmental effects stemming from greenhouse gas (GHG) emissions and reduces associated costs linked to fossil fuel energy sources. Hence, the optimal sizing of a hybrid mix of RES and non‐RES energy sources to power water pumping is essential. This study employs a generalized reduced gradient (GRG) optimization method to ascertain the most effective energy mix for water pumping system (WPS) application by integrating time of use demand response. This is achieved through four scenarios: Scenario 1 (S1) utilizes grid power and Diesel generator (DG) energy sources, Scenario 2 (S2) incorporates grid power, DG, and solar PV, Scenario 3 (S3) integrates grid power, DG, solar PV, and biomass energy sources, while Scenario 4 (S4) incorporates Time of Use (TOU) with the three aforementioned energy sources. The key findings reveal an ideal solution comprising of a mix of renewable PV and biomass along with non‐renewable grid energy source embedded with Time of Use demand response (S4) with optimal energy capacities of 4007 kW of PV, 4228 kW of grid, 234 kW of biomass, and 1085 of DG owing to the least cost energy and cost of water pumped of 0.75$/kW and 1.74$/kL, respectively, most volume of water pumped of 270.50 kL. These findings prove that the integration TOU demand response program with a hybrid mix of grid‐biomass‐DG‐solar PV is best suited for water pumping applications as it gives a cost‐competitive value.

The Confinement Behavior and Mechanistic Insights of Organic Phase Change Material Encapsulated in Wood Morphology Genetic Nanostructures for Thermal Energy Storage.

Wood, a renewable and abundant biomass resource, holds substantial promise as an encapsulation matrix for thermal energy storage (TES) applications involving phase change materials (PCMs). However, practical implementations often reveal a disparity between observed and theoretical phase change enthalpy values of wood-derived composite PCMs (CPCMs). This study systematically explores the confinement behavior of organic PCMs encapsulated in a delignified balsa wood matrix with morphology genetic nanostructure, characterized by a specific surface area of 25.4 ± 1.1 m2/g and nanoscale pores averaging 2.2 nm. Detailed thermal performance evaluations uncover distinct phase change behaviors among various organic PCMs, influenced by the unique characteristics of functional groups and carbon chain lengths. The encapsulation mechanism is primarily dictated by host-guest interactions, which modulate PCM molecular mobility through hydrogen bonding and spatial constraints imposed by the hierarchical pore structure of the wood. Notably, results demonstrate a progressive enhancement of nanoconfinement effects, evidencing a transition from octadecane to stearic acid, further supported by density functional theory (DFT) calculations. This research significantly advances the understanding of nanoconfinement mechanisms in wood-derived matrices, paving the way for the development of high-performance, shape-stabilized composite PCMs that are essential for sustainable thermal energy storage solutions.

Testing of a multi-energy complementary absorption heat pump prototype for combined cooling and heating with large temperature range from − 20 to 90 °C

In the process of carbon neutrality, the comprehensive utilization of clean and renewable energy, including solar, geothermal and biomass, is a potential solution to the low-carbon cooling and heating in distributed areas with weak power grids, such as countryside and suburban. In this paper, an absorption heat pump with multi-energy complementary was built to provide combined cooling and heating. Solar energy was collected through an evacuated tube collector using heat conduction oil, and a gas boiler was adopted to further heat the oil and balance the solar thermal fluctuations. Heat collected in the oil circulation was used to drive an ammonia-water absorption heat pump. A control strategy was proposed to achieve stable energy supply under different weather condition, and efficient operation in wide temperature zone. Environmental test of the prototype was performed in Jinan. The results showed that the prototype ran stably to provide 5-15 kW cooling at −20 to 10 °C, and 20-35 kW heating at 40 to 90 °C, with solar thermal ratio of 20–35 % in different weather conditions, and the renewable energy ratio in heating mode could exceed 55 % through further recovery of ambient heat. Furthermore, the COP for cooling reached 0.30–0.43 at −20 °C cold supply, and 0.70–0.78 at 7 °C cold supply, with cooling water temperatures varied from 30 to 20 °C; and the COP of heating reached 1.40–1.90 at 45 °C heat supply, and 1.35–1.56 at 80 °C heat supply, with evaporation temperature varied from −15 to 20 °C. Results demonstrated that the proposed prototype has significant energy and carbon reduction potential, and is a solution for combined cooling and heating in distributed areas.

Self-sacrificing and self-supporting biomass carbon anode–assisted water electrolysis for low-cost hydrogen production

Electrooxidation of renewable and CO2-neutral biomass for low-cost hydrogen production is a promising and green technology. Various biomass platform molecules (BPMs) oxidation assisted hydrogen production technologies have obtained noticeable progress. However, BPMs anodic oxidation is highly dependent on electrocatalysts, and the oxidation mechanism is ambiguous. Meanwhile, the complexity and insolubility of natural biomass severely constrain the efficient utilization of biomass resources. Here, we develop a self-sacrificing and self-supporting carbon anode (SSCA) using waste corncobs. The combined results from multiple characterizations reveal that the structure-property-activity relationship of SSCA in carbon oxidation reaction (COR). Theoretical calculations demonstrate that carbon atoms with a high spin density play a pivotal role in reducing the adsorption energy of the reactive oxygen intermediate (*OH) during the transition from OH- to *OH, thereby promoting COR. Additionally, the HER||COR system allows driving a current density of 400 [Formula: see text] at 1.24 V at 80 °C, with a hydrogen production electric consumption of 2.96 kWh Nm-3 (H2). The strategy provides a ground-breaking perspective on the large-scale utilization of biomass and low-energy water electrolysis for hydrogen production.