High Inorganic Content Research Articles

Long-life potassium metal batteries enabled by anion-derived solid electrolyte interphase using concentrated ionic liquid electrolytes

Potassium metal batteries (PMBs) show great potential as next-generation energy storage systems yet face challenges such as the dendritic growth of the potassium anode, leading to issues with cycle life and safety. This study reports a potassium salt-concentrated ionic liquid electrolyte (PCIL) consisting of potassium bis(fluorosulfonyl)imide (KFSI) and 1-methyl-1-propyl pyrrolidinium bis(fluorosulfonyl)imide (Pyr13FSI) to achieve long-life and, safe PMBs. PCIL presents several advantages including outstanding oxidation stability (≈5.2 V), decent ionic conductivity (4.0 mS cm−1 at 25 °C), and negligible flammability. Moreover, PCIL promotes the development of anion-derived solid-electrolyte interphase (SEI) with high inorganic content. This not only hinders the growth of potassium dendrites but also facilitates facile interfacial charge transfer kinetics. Benefiting from these advantages, PMBs (K||KVPO4F) employing PCIL exhibit remarkable cycle performances at both ambient and elevated temperatures (capacity retention after 300 cycles: 74.8% at 25 °C and 82.9% at 45 °C), surpassing the performance of conventional carbonate (1 M KPF6 EC/PC) and dilute potassium ionic liquid electrolyte (PIL). This work demonstrates the tangible capability of PCIL in realizing practical PMBs.

Stable Lithium Metal Batteries Enabled by Lithiophilic Core-Shell Nanowires on Copper Foam.

Lithium (Li) metal batteries have attracted considerable research attention due to their exceptionally high theoretical capacity. However, the commercialization of Li metal batteries faces challenges, primarily attributed to uncontrolled growth of Li dendrites, which raises safety concerns and lowers coulombic efficiency. To mitigate Li dendrites growth and attain dense Li deposition, the hybrid SiO2-Cu2O lithiophilic film applied to a 3D copper foam current collector is developed to regulate the interfacial properties for achieving even and dense Li deposition. The SiO2-Cu2O possesses strong Li+ trapping capability through strong lithiophilicity from Cu2O. Additionally, the SiO2-Cu2O enables uniform ion diffusion through the domain-limiting effect of the holes in the SiO2 layer, inducing an even and dense Li plating/stripping behavior at a large capacity. Furthermore, the SiO2 layer promotes the formation of an initial high inorganic content Solid Electrolyte Interphase (SEI) through selective preferential binding with anion and solvent molecules. When the SiO2-Cu2O@Li anode is coupled with a LiFePO4 (LFP) cathode, the resulting full cell exhibits superior cycling stability and rate performance. These results provide a facile approach to construct a lithiophilic current collector for practical Li metal anodes.

Synthesis of transparent polymer hybrids consisting of gelatin, as a natural polymer, and zinc oxide

Abstract Gelatin and zinc oxide (ZnO) polymer hybrids were prepared via the sol–gel reaction of zinc acetate dihydrate in the presence of gelatin. When the gelatin/ZnO ratio was 9/1, a transparent polymer hybrid was obtained. This hybrid contained no phase separations consisting of organic and inorganic phases. Microscopic or submicroscopic aggregations and separations between gelatin and ZnO were clearly observed in the sample with a high inorganic content. The results of thermal analysis showed that the yield of ceramic decreased as ZnO content increased, and a 10% weight loss temperature increased as gelatin content increased. FT-IR measurements suggested the formation of intermolecular interactions, thought to be hydrogen bonds, between gelatin and ZnO. Furthermore, the results of XRD measurements revealed that the hybrid with a ZnO content of 10% is amorphous.

Pyrolysis of biomass harvested from heavy-metal contaminated area: Characteristics of bio-oils and biochars from batch-wise one-stage and continuous two-stage pyrolysis

This study evaluates pyrolysis products obtained from biomasses (silver grass, pine, and acacia) harvested from heavy-metal-contaminated soil. To do so, we utilized two methods: a batch one-stage pyrolysis, and a continuous two-stage pyrolysis. The study results show that the yields and characteristics of bio-oils and biochars varied depending on the pyrolysis process and the type of biomass. The two-stage pyrolysis having two reactors (auger and fluidized bed reactors) appeared to be very suitable for specific chemicals production such as acetic acid, acetol, catechol, and levoglucosan. The biochar obtained from the fluidized-bed reactor of two-stage pyrolysis had high thermal stability, high crystallinity, high inorganic content, and a small number of functional groups. In contrast, the biochar obtained from the one-stage pyrolysis had low thermal stability, low crystallinity, a high carbon content, and a large number of functional groups. The biochar obtained from the two-stage pyrolysis appeared to be suitable as a material for catalyst support and as an adsorbent. The biochar obtained from one-stage pyrolysis appeared to be a suitable as a soil amendment, as an adsorbent, and as a precursor of activated carbon. All biochars showed a negative carbon footprint. In the end, this study, which was conducted using two different processes, was able to obtain the fact that products of pyrolysis biomass contaminated with heavy metals have different characteristics depending on the process characteristics and that their utilization plans are different accordingly. If the optimal utilization method proposed through this study is found, pyrolysis will be able to gain importance as an effective treatment method for biomass contaminated with heavy metals.

Built-in hybrid intercalation cations facilitated fast lithium-ion conduction of lamellar montmorillonite for safety lithium-metal batteries

Solid-state lithium-metal batteries have good prospects such as high theoretical energy density and excellent safety while available solid-state electrolytes cannot meet the electrochemical requirements. In this study, hybrid cations are built-in intercalated in lamellar montmorillonite to facilitate fast lithium-ion conduction, and a stable and safe lithium-metal battery is achieved. The hybrid intercalation cation of the large-size organic molecule cetyltrimethylammonium bromide (CTAB) broadens the insertion space as well as the Li+ insertion ensuring the concentration of interlayer conduction carriers. Based on hybrid intercalated montmorillonite, a 35 μm-thick high inorganic content solid-state electrolyte with excellent flexibility, superior hardness, and heat resistance has been prepared by the solution casting method. This electrolyte possesses high ionic conductivity (7.64 × 10−4 S·cm−1 at 25 °C), low ionic mobility energy (0.16 eV), and a wide window of electrochemical stabilization (4.92 V). With such a high-performance electrolyte, Li symmetric cells are stably cycled over 2000 h at 25 °C with a low overpotential of 30 mV. The Li||LiFePO4 solid-state battery exhibits excellent cycling stability with 94.1 % capacity retention for 200 cycles at 25 °C. This interface regulation and interlayer ion transfer strategy may provide a new method for high-performance solid-state batteries.

Biomass characterization and solvent extraction as tools to promote phenol production from urban pruning

Nowadays, leaves, bark, and branches are generated from the tree-pruning process in urban places, where their management is a problem because of the necessity of disposal. These wastes are lignocellulosic biomasses with poor properties for use in biofuel production, but with interesting projections for building block products such as phenol compounds. Therefore, extensive biomass characterization of urban pruning from Liquidambar styraciflua L. was developed to evaluate its composition as a tool for phenol production through thermal processing, in which solvent extraction is a complementary tool for selectivity improvement. The results showed high lignin content in bark and leaves at 45 and 28 %, respectively, compared with that in branches (14 %). Additionally, high extractives in leaves (14 %) could be an additional source of phenols. The lignin units were analyzed by Raman dispersion, revealing p–hydroxyphenyl (H) units in the bark, guaiacyl (G) units in the bark and leaves, and syringyl (S) units only in the branches. Furthermore, the micropyrolysis coupled with gas chromatography/mass spectrometry assay realized at 600 °C showed high presence of phenolic compounds in the three biomass investigated, where a high phenol concentration was identified in leaves, probably due to the S unit degradation during pyrolysis. With these results, an assay for bio-oil production was performed in a low-temperature pyrolysis reactor using leaves as feedstock, reaching a low bio-oil yield with high water content favored for the high inorganic content of leaves (13 %). The produced bio-oil was used for liquid–liquid extraction evaluation, where 1-octanol and methyl isobutyl ketone were identified as interesting solvents for catechol and phenol extraction, respectively. This article presents the challenge of characterizing each part of urban trees, which could be a tool to promote the use of urban pruning by studying the thermal degradation mechanism to implement processes for high-value products, such as phenols produced from L. styraciflua L.

Ambient solid-state triplet-triplet annihilation upconversion in ureasil organic-inorganic hybrid hosts.

Triplet-triplet-annihilation upconversion (TTA-UC) has attracted significant attention as an approach to harvest low energy solar photons that cannot be captured by conventional photovoltaic devices. However, device integration requires the design of solid-state TTA-UC materials that combine high upconversion efficiency with long term stability. Herein, we report an efficient solid-state TTA-UC system based on organic-inorganic hybrid polymers known as ureasils as hosts for the archetypal sensitiser/emitter pair of palladium(ii) octaethylporphyrin and diphenylanthracene. The role of the ureasil structure on the TTA-UC performance was probed by varying the branching and molecular weight of the organic precursor to tune the structural, mechanical, and thermal properties. Solid-state green-to-blue UC quantum yields of up to 1.86% were observed under ambient conditions. Notably, depending on the ureasil structure, UC emission could be retained for >70 days without any special treatment, including deoxygenation. Detailed analysis of the structure-function trends revealed that while a low glass transition temperature is required to promote TTA-UC molecular collisions, a higher inorganic content is the primary factor that determines the UC efficiency and stability, due to the inherent oxygen barrier provided by the silica nanodomains.

Synthesis of sewage sludge biochar in molten salt environment for advanced wastewater treatment: Performance enhancement, carbon footprint and environmental impact reduction

Sewage sludge (SS) pyrolysis to produce biochar is a vital approach for treating and utilizing SS, while reducing the carbon footprint of SS disposal. However, the high inorganic content in SS results in low carbon content and underdeveloped pore structure of biochar prepared under inert atmospheres. There is a significant risk of secondary pollutant emissions, including CO2, SO2, and NOx. In this study, we propose an innovative approach that utilizes excess molten salts, specifically a Li-Na-K molten carbonate (MC) and a Li-Na-K molten chloride (MCH), to create a medium-temperature liquid phase reaction environment (500 °C) for SS pyrolysis. This environment promotes the functional enhancement of biochar (SSB-MC and SSB-MCH) and in-situ absorption of secondary pollutants. The pore structure of SSB-MC and SSB-MCH are greatly optimized. Thanks to the dissolution of calcium-silicon-aluminum-based minerals by molten salt, the carbon content is also significantly increased. The increased specific surface area and surface-enriched functional groups (O, N, P, etc.) of SSB-MC result in greatly enhanced adsorption performance for Rhodamine B (27.9 to 89.1 mg g−1). SSB-MCH, due to the increased iron and phosphorus doping, also exhibits enhanced Fenton oxidation capability. Life cycle assessments demonstrate that the molten salt processes effectively reduce the carbon footprint, energy consumption, and environmental impact.

Sintered Bottom and Vitrified Silica Ashes Derived from Incinerated Municipal Solid Waste as Circular Economy-Friendly Partial Replacements for Cement in Mortars

Sintered bottom ash (SBA) and vitrified ash (VA) derived from the incineration of municipal solid waste (MSW) at 1200 °C were used in this study as replacements for Type 2 Portland cement (CEM-II) based mortars. This approach negates the need to send them to landfill, benefits the circular economy and contributes towards the decarbonisation of cementitious construction materials in response to international net zero carbon emission agendas. The material (physico-chemical) characteristics of VA and SBA were analysed before being used as partial replacements for CEM-II in mortars, whereby compressive strength (CS) was the primary criterion for assessing engineering performance. VA and SBA replaced CEM-II at dosages of 10%, 25% and 50% based on their high inorganic and pozzolanic contents; whereby the 10% and 25% replacements did not compromise mortar strength. The alkalinity and pozzolanic properties of SBA collectively indicated it has greater potential as a cementitious material over VA, which possessed a neutral pH. The 28-day CS recorded for mixtures containing 25% VA and 10% SBA were 13.74 MPa and 11.77 MPa, respectively compared with 17.06 MPa for CEM-II control samples. The use of 2% additional water in 25% SBA mortar designs improved strength further, indicating that SBA’s water retention properties permitted further hydration and strength development with curing. Microstructural, mineralogical and infrared spectroscopy analyses indicated that these strengths were owed to the formation of silicate-based hydration products. The outcomes from this study highlight that SBA has potential for replacing CEM-II and VA as a filler in cementitious mortar.Graphical

Advancing produced water treatment: Scaling up EC-MF-MDC technology from lab to pilot scale

Membrane distillation integrated with crystallization (MDC) holds promise for sustainable produced water treatment. Addressing challenges like fouling and wetting, common due to high inorganic content and oil-grease presence, requires efficient pretreatment for stable performance. To establish a compact, manageable treatment solution, we examined a pilot-scale integrated electro-coagulation (EC) - microfiltration (MF) system as pretreatment. This step produced 3600 L daily, significantly improving water quality. A remarkable 40% reduction in total organic carbon, 22-fold decrease in total suspended solids, and 600-fold decrease in turbidity underscore its effectiveness. This enhances the suitability for subsequent membrane distillation. In addition, a significant decrease in fouling and scale formation was observed. Long-term batch and continuous MD tests investigated crystallization between MD cycles that prevents significant flux decline. Implementing continuous MDC increased total water recovery six-fold, with stable membrane performance over six cycles, recovering approximately 10% of feed per cycle. These observations highlight the scalable potential of the less-explored integrated treatment (EC-MF-MDC) for effective produced water treatment. This study suggests the viability of the integrated approach for sustainable, larger-scale produced water treatment.

Processing of membranes and 3D scaffolds based on n-TiO2 colloidally dispersed on a thermoplastic matrix for photocatalytic pollutant removal

One of the most promising technologies for water treatment today is photocatalytic membrane reactors (PMRs). Manufacturing efficient membranes is still challenging as many factors are involved, like the porosity, specific surface area, nature and size of particles. In this work, a colloidal method to self-support commercial nanoparticles (n-TiO2) in a polymeric matrix of polylactic acid (PLA) is proposed allowing the fabrication of 2D and 3D structures with high inorganic content that can be adapted to the PMR configurations. Using a commercial filament of PLA loaded with up to 15 vol% of n-TiO2 as starting point, photocatalytic membranes have been manufactured by FFF. In addition, following a similar process, tapes with n-TiO2 particles up to 15 vol% have been processed by tape casting. Thermal characterisation (DTA) and dynamic rheometry evaluated the commercial filament for printing to determine the conditions used during the thermal extrusion and printing processes. FTIR and XRD technologies were used to determine the chemical interactions of PLA matrices with TiO2 nanoparticles. Porosity was measured by Archimedes's method for the filaments, by mercury intrusion for the membranes and by optical microscopy for the scaffolds. Finally, the microstructure of the 2D and 3D pieces was evaluated by scanning microscopy. 2D tape cast membranes were compared with individual filaments and 3D printed scaffolds in linear and gyroidal geometries. The catalytic activity results indicate that tape cast membranes show much higher kinetic constants than the individual filaments and the linear and gyroidal scaffolds. Regarding the two different printed scaffolds, in contrast to the kinetic values, gyroidal geometries achieve an average degradation time (t50) of 6.1 h, which is a lower value than those observed for linear scaffold geometries. Methyl orange degradation tests after 24 h exposure under UV light showed degradation rates of 98% for membranes, 90% for commercial filaments, 80% for gyroidal scaffolds and 60% for linear patterns. Therefore, these results are promising as a solution for fabricating easily extractable self-supported membranes for water treatment in PMRs.

Foraging on sand particles: Coatings of soft radular teeth (Paludomidae, Gastropoda, Mollusca)

AbstractThe radula is the ingesta‐gathering structure in Mollusca. As interface, it has to perform various tasks without functional deterioration caused by wear. Wear prevention is well investigated in mollusks that forage on rocks and that generate high punctual pressure with their hard teeth, which contain high inorganic contents at their tips. In mollusks that forage on softer substrate, such as sand surfaces, and have relatively soft teeth, wear prevention has not been a focus of study before. Here, we studied the teeth of Limnotrochus thomsoni, which are used for raking algae from sand. For comparison, we investigated the soft outer teeth of Lavigeria grandis, which are used in gathering particles after the ingesta is loosed from the rock surface. SEM revealed scratches on all surfaces of the teeth and suggests that every tooth side interacts with abrasive particles during foraging. Analysis of stomach content revealed that sand particles of 10–20 μm diameter are ingested. By EDX/EDS, we studied the composition of the teeth and determined that high proportions of Ca are present on all surfaces, which could be an adaptation to reduce abrasion. Finally, we here present evidence for the existence of a canal within the teeth, which could potentially serve as delivery pathway of minerals during tooth maturation and has not been previously detected in Gastropoda.

Propensity of a low-cost adsorbent derived from agricultural wastes to interact with cationic dyes in aqueous solutions.

Ash collected from thrown-away by-products while preparing a popular traditional food additive, kolakhar of the Assamese community of North East, India, was used as an alternate cost-effective, porous bioadsorbent option from the conventional activated carbon for the purification of carcinogenic dyes laden water. The base material for kolakhar preparation was taken from the discarded banana stem waste to stimulate agricultural waste management. Methylene blue (MB) and basic fuchsin (BF) dyes were used as model cationic dyes. Characterization techniques like CHN, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX), and Brunauer-Emmett-Teller (BET) analysis of the prepared banana stem ash (BSA) reveal the presence of high inorganic contents and functional groups in the irregular, porous bioadsorbent with surface area 55.534 m2g-1. Various regulating parameters studied to optimize the adsorption capacity of BSA were bioadsorbent dose (0.1-3g/L), temperature (298-318K), contact time (0-150min), pH (2-9), and initial dye concentrations (10-40mg/L). Non-linear kinetic models suggested Elovich for both MB and BF adsorption, while the non-linear isotherm model suggested Langmuir and Temkin for MB and BF adsorption, respectively, as best-fitted curves. The monolayer adsorption capacity (qm) for MB and BF was 15.22mg/g and 24.08mg/g at 318K, respectively, with more than 95% removal efficiency for both dyes. The thermodynamic parameters studied indicated that the adsorption is spontaneous. The ∆H0 values of MB and BF adsorptions were 2.303kJ/mol (endothermic) and - 29.238kJ/mol (exothermic), respectively.

Content of nitrate and nitrite in commercial and self-made beetroot juices and the effect of storage temperature.

Popularity of beetroot juice (BJ) is growing due to its high inorganic nitrate content and its potential physiological benefits. However, the content of is not indicated in most commercial BJs and it can be affected by seasonal changes and storage conditions. This study analyzed the content of and nitrite in five and two commercial and self-made BJs, respectively, that were purchased in the summer and winter periods. The effect of storage temperature (20°C, 4°C, and -20°C) and pH was also analyzed. In nonconcentrated BJs, the content was 34 ± 20% (p = .075) in the winter than in the summer. was fully degraded in self-made BJ after 3 days at 20°C. This effect was attenuated by 78% and 82% when it was kept at 4°C and -20°C, respectively. The addition of lemon juice (5%) to self-made BJ was another useful approach to avoid degradation for 3 days when it was kept at 20°C. Regarding , self-made BJ had higher concentration (0.097 ± 0.01 mg/mL) compared to commercial BJs (<0.1 mg/mL; p = .001). The pH of self-made BJ was higher (6.3 ± 0.1) compared to commercial BJs (4.5 ± 0.3; p = .001). These results suggest that the content of in nonconcentrated BJs can substantially differ across the year and this is an important factor to take into account when recommending BJs to promote some of its potential physiological benefits.

Nutrient-rich submarine groundwater discharge increases algal carbon uptake in a tropical reef ecosystem

Submarine groundwater discharge (SGD) in high volcanic islands can be an important source of freshwater and nutrients to coral reefs. High inorganic nutrient content is generally thought to augment primary production in coastal systems but when this is delivered via a freshwater vector as is the case with SGD in this study, the effects on productivity are unclear. In the current literature, there is limited evidence for a direct association between SGD and primary productivity of reefs. To elucidate the response of primary productivity to SGD, we conducted spatially and temporally explicit in situ benthic chamber experiments on a reef flat along a gradient of SGD. We found significant quadratic relationships between C-uptake and SGD for both phytoplankton and the most abundant macroalga, Gracilaria salicornia, with uptake maxima at SGD-derived salinities of ~21−22 (24.5−26.6 μmol NO3-L−1). These results suggest a physiological tradeoff between salinity tolerance and nutrient availability for reef primary producers. Spatially explicit modeling of reefs with SGD and without SGD indicate reef-scale G. salicornia and phytoplankton C-uptake decreased by 82% and 36% in the absence of SGD, respectively. Thus, nutrient-rich and low salinity SGD has significant effects on algal C-uptake in reef systems.

Investigating the Chemical Composition of Lanolin Waste to Improve the Production of Sustainable Natural Fibre Materials

e Natural Fibre Company process raw wool into natural fibre materials utilising several processing steps. During the manufacturing, intermittent difficulties downstream of the scouring process of raw wool were encountered. Critically, the formation of an unknown paste- like grease deposit - which lead to downstream complications. To characterise the unknown by- product, the chemical composition of different raw wool lanolin extracts routinely employed in the manufacture of fibres were compared against a sample of the unknown grease deposit using high-temperature gas chromatography coupled with mass spectrometry. Major components of the unknown grease were putatively identified as psi-cholesterol, pentadecenol, palmitic and oleic acid, and a homologous series with mass spectra consistent with glycol ethers. The identification of chemicals predominantly with high interfacial properties was indicative of a potential issue with the surfactants used in the scouring process. the high inorganic content could indicate the presence of potassium salts derived from the suint, warranting further investigation of the inorganic fraction using inductively coupled plasma-optical emission spectroscopy or mass spectrometry.

Inorganic phosphate content does not affect oviposition preference in the invasive pest Drosophila suzukii

AbstractThe broad variation in host use among polyphagous insects is well documented but still poorly understood. In numerous pest insects, the proximate mechanisms responsible for variation in oviposition preference among host plants remain to be elucidated. The invasive crop pest, Drosophila suzukii, attacks a wide range of host fruits. Females prefer ovipositing on particular fruit media (blackberry, cherry, blackcurrant) that are rich in phosphorus. As phosphorus is known to be involved in female reproduction in insect species such as Drosophila, it could drive oviposition preference in D. suzukii. Phosphorus is either present as inorganic or organic phosphate in fruits. As the absolute content in macromolecules associated with phosphate in fruits (i.e. proteins and carbohydrates) do not affect oviposition in D. suzukii, we tested for the effect of inorganic phosphate on oviposition preference. We measured the egg‐laying preferences of D. suzukii in a choice environment containing 12 artificial media with increasing content in inorganic phosphate (monopotassium dihydrogen phosphate). In our assay, D. suzukii females did not prefer ovipositing in media with high inorganic phosphate content compared to media with lower inorganic phosphate content. As a confirmation, we verified the previous result of a higher female preference for media made of phosphorus‐rich fruits (blackberry, cherry, blackcurrant). The higher preference for phosphorus‐rich fruits could be driven by macromolecules containing phosphorus (e.g. phospholipids) or by the presence of one or more molecules that do not contain phosphorus, but that happen to be correlated to fruit phosphorus content. Studying the proximate mechanisms driving host use will ultimately help improve the management of D. suzukii and other crop pests.

Evaluation of ‘surgery-friendly’ bone scaffold characteristics: 3D printed ductile BG/PCL scaffold with high inorganic content to repair critical bone defects

The repair of irregular and complex critical bone defects remains a challenge in clinical practice. The application of 3D-printed bioceramics particle/polymer composite scaffolds in bone tissue engineering has been widely studied. At present, the inorganic particle content of the composite scaffolds is generally low, resulting in poor osteogenic activity. However, scaffold with high inorganic content are highly brittle, difficult to operate during surgery, and cannot be in close contact with surrounding bones. Therefore, it is of great significance to design a ‘surgery-friendly’ scaffold with high bioceramic content and good ductility. In this study, we used the solvent method to add high concentration (wt% 70%) bioglass (BG) into polycaprolactone (PCL), and polyethylene glycol was used as plasticizer to prepare 70% BG/PCL composite scaffolds with high ductility using 3D printing technology. In vitro experiments showed that the scaffold had good mechanical properties: easy extension, easy folding and strong compressive resistance. It also showed good performance in biocompatibility and osteogenic activity. It was further observed that compared with pure BG or PCL implantation, the scaffold with higher BG content could have more new bone tissue appeared after 12 weeks. All these results indicate that 3D-printed 70% BG/PCL scaffolds have great potential for personalized repair of bone defects.

A meta‐analysis on the impacts of different oxidation methods on the surface area properties of biochar

AbstractBiochar has a beneficial impact on agricultural prosperity, according to numerous studies, and the key dispute presently is how to maximize that impact. Biochar oxidation is well‐known as one of the accepted methods for increasing biochar efficiency. However, due to contradictory data presented in studies and because biochar is derived from diverse oxidation procedures, as well as, the lack of an analytical comparison between different methods, oxidation data sets require a thorough assessment that can be covered by meta‐analysis. In this study, the effects of the five most common oxidation methods in the literature, namely oxidation by acids, alkaline, metal oxides, physical, and natural oxidation, on the cation exchange capacity (CEC), micro‐pores (MP), specific surface area (SSA), and oxygen‐content functional groups (OFGs) of biochar, were meta‐analyzed. When pyrolysis conditions varied, the efficiency of various operations was also addressed. The most efficient method was acidic oxidation, which increased CEC, SSA, MP, and OFGs by 46%, 43%, 55%, and 72%, respectively. Additionally, increasing the pyrolysis temperature above 550°C is critical for lowering OFGs, which has an impact on biochar sorption characteristics. According to the findings, biochar oxidation (post‐pyrolysis) is important since it creates more oxide ions on the surface area than feedstock oxidation (pre‐pyrolysis). Due to their high inorganic nutrient content, crop residues such as rice husk, maize stalk, and rapeseed stem, which were classed in the intermediate group in this study, are promising feedstocks for synthesizing biochars with high SSA, MP, and CEC. Overall, when compared to other approaches, the acidic process significantly improves the surface properties of biochar.

Prestrain Programmable 4D Printing of Nanoceramic Composites with Bioinspired Microstructure.

Four-dimensional (4D)printing enables programmable, predictable, and precise shape change of responsive materials to achieve desirable behaviors beyond conventional three-dimensional (3D) printing. However, applying 4D printing to ceramics remains challenging due to their intrinsic brittleness and inadequate stimuli-responsive ability. Here, this work proposes a conceptional combination of bioinspired microstructure design and a programmable prestrain approach for 4D printing of nanoceramics. To overcome the flexibility limitation, the bioinspired concentric cylinder structure in the struts of 3D printed lattices are replicated to develop origami nanoceramic composites with high inorganic content (95wt%). Furthermore, 4D printing is achieved by applying a programmed prestrain to the printed lattices, enabling the desired deformation when the prestrain is released. Due to the bioinspired concentric cylinder microstructures, the printed flexible nanoceramic composites exhibit superior mechanical performance and anisotropic thermal management capability. Further, by introducing oxygen vacancies to the ceramic nanosheets, conductive nanoceramic composites are prepared with a unique sensing capability for various sensing applications. Hence, this research breaks through the limitation of ceramics in 4D printing and achieves high-performance shape morphing materials for applications under extreme conditions, such as space exploration and high-temperature systems.