Maximum Density Research Articles

Experimental Investigations of stabilization of Black cotton soil

Abstract The technique of stabilizing soil aids in achieving the qualities of soil that are necessary for building projects. Black cotton soils, sometimes referred to as swelling soils, are those soil types that have a propensity to expand and contract in response to changes in moisture content. By increasing the strength of the black cotton soil, this experimental investigation on stabilizing the soil with a certain amount of granite dust produces positive results. The maximum dry density and reduced potential for shrinkage and swelling are found in the black cotton soil mixed with 5% granite. The greatest results are obtained with 10% of the granite mix with black cotton soil since this experiment shows a significant decrease in the ideal moisture content.

Phase evolution and chemical durability of Ca2Nd8(SiO4)6O2 glass-ceramics derived from CFA via microwave heating designed to immobilize trivalent actinides

Oxyapatite (Ca2Nd8(SiO4)6O2) glass-ceramics (GCs) derived from coal fly ash (CFA) via microwave heating were fabricated to immobilize trivalent actinides (An3+). The effects of the Nd content and sintering temperature on the phase evolution of Ca2Nd8(SiO4)6O2 GCs were systematically investigated. The chemical durability of the Ca2Nd8(SiO4)6O2 GCs waste forms was examined under different leaching conditions (pH 4.0, 6.7, and 10.0). Results demonstrated the transformation of phase from glassy to Ca2Nd8(SiO4)6O2 GCs, when the doping content of Nd2O3 was 10, 15, and 20 wt.% at 1100, 1200, and 1300 °C, respectively, and the maximum solid solution was more than 30 wt.%. Prior to this solid solubility limit, all the Nd(Ⅲ) was incorporated to the glassy phase, whereas when the limit was exceeded, the Nd(Ⅲ) was immobilized into Ca2Nd8(SiO4)6O2 GCs. Moreover, the bulk density of the solidified sample increased with increasing of Nd-doped amount in the temperature range of 1100-1300 °C. The sample that was doped with 30 wt.% Nd2O3 and sintered at 1300 °C, exhibited the maximum bulk density (3.24 g·cm-3). Importantly, the GC waste forms exhibited superior leaching resistance, and the leaching rate of Nd element was in the order of 10-7 - 10-6 g·m-2·d-1. The NLNd values of the samples doped with 30 wt.% Nd2O3 and sintered at 1100 and 1300 °C were 8.57×10-8 g·m-2·d-1 and 4.29×10-8 g·m-2·d-1, respectively, after 28 d. In particular, the leachability of Nd element under different leaching conditions followed the order of acidic ＞ alkaline ＞ neutral. Therefore, Ca2Nd8(SiO4)6O2 GCs derived from CFA via microwave heating are promising immobilization substrates for the immobilization An3+ nuclear waste.

Advanced electrocatalytic performance of the configuration entropy cobalt-free Bi0.5Sr0.5FeO3–δ cathode catalysts for solid oxide fuel cells

The medium-entropy perovskite oxide Bi0.5Sr0.5Fe0.85Nb0.05Ta0.05Sb0.05O3–δ (BSFNTS) is evaluated as a potential cathode catalyst for solid oxide fuel cells (SOFCs). The crystal structure, electrocatalytic activity, oxygen reduction kinetics, and CO2 tolerance are systematically investigated. At 700 °C, the BSFNTS cathode exhibits excellent electrochemical performance with a polarization resistance as low as 0.095 Ω cm2. The maximal power density of the fuel cell with the BSFNTS cathode is 900 mW cm−2. Furthermore, the rate control step for the oxygen reduction reaction (ORR) of the electrode is primarily identified as the adsorbed and diffusion process of the molecule oxygen. The BSFNTS electrode presents excellent CO2 tolerance and durability in a CO2-containing atmosphere, which is related to the high acidity of Bi, Nb, Ta, and Sb cations and the larger average bonding energy of BSFNTS. The preliminary results indicate that BSFNTS medium-entropy oxide is an attractive cathode electrocatalyst for SOFCs.

Beyond Traditional fuel cells: Development and a comprehensive analysis of mechanically Robust metal mesh-supported solid oxide fuel cell

At elevated operating temperatures, a large temperature gradient can cause irreparable damage to the solid oxide fuel cells (SOFCs) stack, eventually interrupting the durability of the stack. Metal substrate support could be used to overcome this challenge. However, the application of metal substrate support poses various challenges such as different thermal expansion coefficients, pore diameters, and complex fabrication techniques. Therefore, a first-ever novel and mechanically strong ferritic stainless-steel metal mesh-supported SOFC design is developed to mitigate these challenges. The metal mesh of 200 μm thickness is laminated with tape-casted green films of anode-support, anode functional layer (AFL), and electrolyte films of SOFC. The iso-static pressure of 300 MPa exhibits a firm attachment of the green films of SOFC with the metal mesh. Subsequently, the metal mesh-supported planar SOFC exhibits 3.3 times higher flexural strength compared to the conventional commercial anode-supported planar SOFC. The nano-CuO is added to constituent layers as a sintering aid to attain the maximum density at a lower sintering temperature of 1100 °C. The result shows that the practical application of the metal mesh-supported cell technology has a great potential to overwhelm the mechanical durability of SOFCs.

Exploring the Electrochemical Performance of Molybdenum Disulfide Nanoparticles Entrenched in Miscible Poly(methyl methacrylate)-Poly(lactic acid) Blends as Freestanding Electrodes for Supercapacitors.

The focus of the study in this article is analyzing the electrochemical properties of molybdenum disulfide on miscible poly(methyl methacrylate)-poly(lactic acid) blends for supercapacitors. The interaction between molybdenum disulfide and miscible poly(methyl methacrylate)-poly(lactic acid) blends, affinity toward water, surface morphology, and mechanical properties are inspected by Fourier transform infrared spectroscopy, water contact angle, scanning electron microscopy, and universal testing machine, respectively. Among the developed membranes, 0.75 wt% of molybdenum disulfide on poly(methyl methacrylate)-poly(lactic acid) shows better electrochemical performances. It exhibits a maximum specific capacitance of 255.5 F g-1 at a current density of 1.00 mA g-1, maximum energy density of 22.7 Wh kg-1, and maximum power density of 360 W kg-1. A cycle study reveals 92% capacitance retention after 2500 cycles. The designed supercapacitor device shows a maximum specific capacitance of 1240 μF g-1 at a current density of 0.5 μA g-1, maximum energy density of 43 μWh kg-1, and maximum power density of 700 μW kg-1. Flexible membranes of molybdenum disulfide are expected to be a potent combination for supercapacitor applications.

Diagnosis of hemostatic system disorders in patients with chronic heart failure using classical and integral methods

BACKGROUND: The state of the hemostatic system in patients with chronic heart failure (CHF) remains an insufficiently studied problem. PURPOSE OF THE STUDY: to present the results of an original study of the coagulation system of patients with CHF using an integral technique — low-frequency piеzothromboelastography (LPTEG). MATERIAL AND METHODS: The study involved 90 patients with CHF due to hypertension and coronary artery disease aged 50–75 years. The subjects were divided into groups with CHF I–IIa (n = 30), CHF stages IIb–III (n = 60). All patients underwent a study of the hemostasis system using classical (coagulogram) and integral (NPTEG) methods before prescribing antiplatelet and anticoagulant therapy. The comparison group consisted of healthy patients of the same age group without CHF (n = 30). RESULTS: In patients with CHF, a general blood test revealed a statistically significant decrease in the number of platelets (group 1 — 215; group 2 — 185) compared to the control group — 241. When analyzing the coagulogram, a decrease in the levels of prothrombin (group 1 — 89; group 2 — 86; control group 105), antithrombin-III (group — 76.5; group 2 — 73; control group — 91) and increased INR (group 1 — 1.03; group 2 — 1.12; control group 1.01) in patients in groups with CHF compared to the control group (p 0.05). When using the NPTEG method in patients with CHF, a decrease in indicators characterizing the rate of clot polymerization (intensity of clot polymerization) and clot density (maximum amplitude) was determined when compared with the control group (p 0.05). CONCLUSION: In patients with CHF, changes in the hemostatic system are determined, characterized by a tendency to hypocoagulation, the frequency a severity of which increases with the progression of the stage of the disease.

Room-temperature synthesis of VO(OH)2 as a high capacity cathode material for aqueous zinc ion batteries

The development of satisfactory cathodes plays a key role in the widespread utilization of aqueous zinc ion batteries. Cathode materials with high specific capacity and long cycling life are still urgently needed for aqueous zinc ion batteries. Herein, a new cathode material VO(OH)2 is synthesized by a facile room-temperature precipitation approach, and its electrochemical characteristics and structural evolution process are investigated. Benefiting from its intrinsic electrochemical activity, the VO(OH)2 cathode exhibits a remarkable specific capacity of 488 mAh g−1 at 0.1 A g−1, retains a high capacity of 219.1 mAh g−1 at the increased current density of 10 A g−1, and provides a maximum energy density of 439.2 Wh kg−1. In addition, when subjected to a 12,000 cycles charge/discharge test at 10 A g−1, the cathode retains a capacity of 185.8 mAh g−1, highlighting durable cycling performance. The structural evolution analysis reveals that of VO(OH)2 cathode may be in-situ transformed to an amorphous vanadium oxide V2O5-x in the first charging process, which could reversibly intercalate/deintercalate zinc ions. This research supplies a promising cathode material for aqueous zinc ion batteries and enhances understanding of vanadium oxyhydroxide in metal ion storage.

Phosphorus oxide promoted solid state hydrolysis of sodium borohydride for efficient onsite hydrogen production

The hydrolysis of solid sodium borohydride (NaBH4) as a hydrogen source for portable fuel cells offers the advantages of excellent safety and convenient storage, making it the optimal alternative to NaBH4 solutions. However, the hydrolysis process is relatively slow and requires the addition of a catalyst to enhance its efficiency. Recent studies have demonstrated that introducing H+ can effectively promote the hydrolysis of NaBH4. In this study, therefore, selects solid acid anhydride, phosphorus pentoxide (P2O5), as a promoter for the hydrolysis of NaBH4. By controlling the ratio of H+ to H− in the NaBH4–P2O5 system, the conditions for hydrogen production via NaBH4 hydrolysis are optimized. Subsequently, to cater to the requirements of portable fuel cell applications, the optimal NaBH4–P2O5 hydrogen production system is selected, with hydrogen generation rate being controlled by regulating water flow speed. In order to enhance the practical applicability of NaBH4–P2O5, the scale-up of hydrogen production from this system is also undertaken. Finally, to validate the practicality of this reaction system, integration with a proton exchange membrane fuel cell (PEMFC) toy car using the NaBH4–P2O5 hydrogen generation system is performed. The results indicate that a NaBH4 conversation exceeding 90 % can be achieved when the ratio of H+ to H− is approximately 0.14, and within the range of H+/H− ratios from 0.05 to 0.14, the maximum hydrogen density reached 6 %. Furthermore, it was found that adjusting the water flow rate only impacts the rate of hydrogen production without significantly affecting the NaBH4 conversion, which consistently surpassed 90 %. Similar high NaBH4 conversion, above 90 %, were also attained in the scaled-up experiments of the NaBH4–P2O5 system. When implemented in a 5W PEMFC, this hydrogen production system delivered an output power of approximately 1.76 W, thereby affirming its operational feasibility and effectiveness.

Synergy of Oxygen Octahedra Distortion and Polar Nanodomains Induced Emergent Electrocaloric Effect in NaNbO3-Based Ceramics.

High-performance electrocaloric materials are essential for the development of solid-state cooling technologies; however, the contradiction of the electrocaloric effect (ECE) and temperature span in ferroelectrics frustrates practical applications. In this work, through modulating oxygen octahedra distortion and short-range polar nanodomains with moderate coupling strength, an EC value of ΔT ∼ 0.30 K with an ultrawide temperature span of 85 K is obtained in the x = 0.04 composition [(0.88 - x)NaNbO3-0.12BaTiO3-xLiSbO3 (x = 0-0.06)]. The LiSbO3 dopant induces a P4bm-to-R3cH phase transition and intensifies the oxygen octahedra distortion degree, accompanied by the ferroelectric domain smashing into polar nanodomains. Also, LiSbO3 addition enhances the relaxation degree with a downshift of Tfd (ferroelectric-to-diffuse phase transition temperature) and TJ (temperature of the maximal current density value), and Tfd is shifted to near room temperature with an absence of TJ in x = 0.04. Local energy barriers induced by oxygen octahedra distortion inhibit the phase transition in conjunction with activation of short-range polar order switching under thermal stimuli, which is the underlying mechanism for an excellent EC performance for x = 0.04. This work not only clarifies that ferroelectrics with oxygen octahedra distortion and short-range polar order are expected to achieve remarkable EC performances but also provides a design strategy to seek emergent EC behaviors in complex oxygen-octahedra-distortion materials.

Integrated construction improving electrochemical performance of loadable supercapacitors based on porous cement-based solid electrolytes

Emerging integrated loadable supercapacitors (ILSs) are prominent candidates for zero-energy buildings with both load-bearing/energy storage capacity. However, the development of solid electrolytes with good mechanical and electrochemical performance remains a major challenge in realizing an integrated electro-mechanical system. Herein, the porous cement-based solid electrolytes (PCSEs) with the combined characteristics of high ionic conductivity and certain compressive strength are successfully developed by a facile “killing two birds with one stone” chemical foaming strategy using potassium iodide (KI) as the reaction modifier, and hydrogen peroxide (H2O2) and Portland cement as the foaming agent and substrate, respectively. The KI is introduced to balance the paradoxical relationship between ionic conductivity and compressive strength while improving the pseudocapacitance of the electrode. Benefiting from these intriguing integrated characteristics, the symmetrical ILS assembled with PCSE and reduced graphene oxide (rGO) electrodes can deliver a maximal energy density of 21.6 Wh kg−1 and a power density of 1106.2 W kg−1. Meanwhile, the ILS exhibits stable electrochemical behavior when withstanding external forces, which is a rarely studied aspect in other reports. Our results provide the basis for simple and universally applicable systems that fulfill the requirements of structural energy storage for civil engineering.

Contrast enhancement boost improves the image quality of CT angiography derived from 80-kVp cerebral CT perfusion data

Rationale and objectiveTo investigate the impact of the contrast enhancement boost (CE-boost) technique on the image quality of CT angiography (CTA) derived from 80-kVp cerebral CT perfusion (CTP) data, and to compare it with conventional CTApeak as well as other currently employed methods for enhancing CTA images, such as CTAtMIP and CTAtAve extracted from CTP.Materials and methodsThe data of forty-seven patients who underwent CTP at 80 kVp were retrospectively collected. Four sets of images: CTApeak, CTAtMIP, CTAtAve, and CE-boost images. The CTApeak image represents the arterial phase at its peak value, captured as a single time point. CTAtMIP and CTAtAve are 4D CTA images that provide maximum density projection and average images from the three most prominent time points. CE-boost is a postprocessing technique used to enhance contrast in the arterial phase at its peak value. We compared the average CT value, standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the internal carotid artery (ICA) and basilar artery (BA) among the four groups. Image quality was evaluated using a 5-point scale.ResultsThe CE-boost demonstrated and CNR in the ICA and BA (all p < 0.001). Compared with the other three CTA reconstructed images, the CE-boost images had the best subjective image quality, with the highest scores of 4.77 ± 0.43 and 4.87 ± 0.34 for each reader (all p < 0.001).ConclusionCompared with other currently used techniques,CE-boost enhances the image quality of CTA derived from 80-kVp CTP data, leading to improved visualization of intracranial arteries.

β-ketoenamine-linked covalent organic frameworks ultrathin film for transparent supercapacitors with enhanced charge storage capability

With the development of electronic products toward optical transparency and intelligent portability, transparent supercapacitors (TSCs) have been considered as one of the ideal and efficient power sources. However, it is still a challenge to explore covalent organic frameworks (COFs) based transparent conductive electrodes (TCEs) with high photoelectric property and capacitive activity. Herein, β-ketoenamine DqTp (DAAQ-TFP, DAAQ = 2,6-diaminoanthraquinone, and TFP = 1,3,5-triformylphluroglucinol) COFs ultrathin films are synthesized for TCEs through the Schiff base reaction of DAAQ and TFP. The DqTp ultrathin films fully expose the redox-active anthraquinone moieties, shorten the ion/electron transport path, accelerate the transport and diffusion rate, and thus enhance charge storage capability. DqTp-1 TCEs possess the excellent optoelectronic property with optical transmittance (T550 nm) of 69.46%, sheet resistance (Rs) of 7.45 Ω sq−1, and remarkable areal capacitance (CA) of 355.67 μF cm−2. The corresponding asymmetric DqTp-1//PANI TSCs (T550 nm = 58.06%) yield a high CA of 64.55 μF cm−2 at 3 μA cm−2 and have a maximum areal energy density of 0.015 μWh cm−2 at 1.95 μW cm−2. After 5000 cycles, the capacitance retention is 96.9%. This work provides key insights into the design and synthesis of transparent redox-active COFs-based TSCs with excellent photoelectric property and enhanced charge storage capability.

Systematic study of the N concentration effects on metal-free ORR electrocatalysts derived from corncob: Less is more

We report nitrogen-doped biomass-derived porous carbon materials with great performance for the Oxygen Reduction Reaction (ORR) in alkaline media. The level of nitrogen doping in a simple pyrolysis of corncob (CC) was varied systematically, a 1:1 CC:urea ratio (CC1U) gave the best performance in terms of onset potential (Eonset = 0.97 V vs. RHE), maximum current density (jmax = -3.22 mA cm−2), hydroperoxide ion yield (%HO2– = 1.18 % at 0.5 V), and electron transfer number (n = 3.86 at 0.5 V). Unexpectedly, for higher CC:urea ratios the doping decreases, instead of plateauing, with lower concentration of C-N sites and more sp2 sites as determined by XPS, as well as lower specific surface area (SSA), while increasing both porosity and carbon (002) interplanar distance (d(002)). These materials should be durable and robust, since their performance actually improved after accelerated degradation tests. This study proves that renewable “waste” can be upconverted into metal-free electrocatalysts for electrochemical energy conversion technologies and emphasizes the need for studying and controlling doping levels to enhance performance.

Effects of Palm Kernel Shells (PKS) on Mechanical and Physical Properties of Fine Lateritic Soils Developed on Basalt in Bangangté (West Cameroon): Significance for Pavement Application

The utilization of an agricultural waste product known as palm kernel shells (PKS) combined with fine laterites (from basalt in Bangangté, West Cameroon) to produce low-cost and innovative materials with good bearing capacities for road pavement was investigated. Fine laterites from two soil profiles (BL31 and BL32) and made up of kaolinite, hematite, goethite, gibbsite, anatase, ilmenite and magnetite minerals were partially replaced with PKS at 15%, 25%, 35%, and 45% by weight. Physical and mechanical tests, including particle size distribution, Atterberg limits, unsoaked and soaked California Bearing Ratio (UCBR and SCBR), unconfined compressive strength (UCS), and tensile strength (Rt), were performed on the different mixtures. After the addition of PKS, a decrease in fine particle content (77 to 38%), liquidity limit (LL: 72 to 61%), plasticity index (PI: 30 to 19%), maximum dry density (MDD: 1.685 to 1.29 t/m3), and optimum moisture content (OMC: 27.5 to 24.0%) was noticed. Additionally, there was an increase in UCBR (16–72%), SCBR (14–66%), UCS (1.07–7.67 MPa), and Rt (2.24–9.71 MPa). This allows new materials suitable for the construction of base layers for low trafficked roads (T1–T2), as well as sub-base and base layers for high trafficked roads (T3), to be obtained. This newly formed material can be recommended locally for road construction works, though more in-depth studies are required.

Tough and temperature-tolerance cellulose/polyacrylic acid/bentonite hydrogel with high ionic conductivity enables self-powered triboelectric wearable electronic devices

Solid-state zinc-ion hybrid supercapacitors (ZHSCs) featuring hydrogel electrolytes have become ideal for large-scale flexible energy storage. However, existing polyacrylic acid (PAA) hydrogel electrolytes often lack the combined traits of ionic conductivity, mechanical robustness, and temperature tolerance. Herein, a versatile PAA-based hydrogel electrolyte (ACBH-Zn) containing a ZnCl2-cellulose solution and bentonite (BT) is delivered, facilitated by cooperative coordination bonds and hydrogen bonds. The coordination bonds between Zn2+ and −COOH of PAA, in conjunction with cellulose and BT, alongside the abundant hydrogen bonds within cellulose and PAA, are conducive to upgrading mechanical strength and ionic conductivity, while the BT's lamellar structure further provides sufficient ion migration channels. Consequently, the ACBH-Zn showcases exceptional mechanical properties, satisfying ionic conductivity (88.9 mS cm−1), and excellent temperature tolerance at −60 °C (30.3 mS cm−1). The ACBH-ZHSC, when assembled, attains a remarkable maximum energy density (323.4 Wh kg−1), maintaining an impressive capacity retention rate (92 %) even after undergoing 10,000 cycles at 10.0 A g−1. Furthermore, the assembled self-powered triboelectric wearable electronic device effectively converts mechanical energy from human movement into electrical energy, enabling efficient storage and utilization, and offering promising insights into the application of flexible wearable devices.

The temperature of maximum in density of aqueous solutions of nitrate and ammonium salts: Testing the Madrid-2019 force field.

The shift in the temperature of maximum in density (TMD) at room pressure of aqueous solutions of a set of five salts containing NO3- and/or NH4+ groups is studied both through experiments and through molecular dynamics simulations using the Madrid-2019 force field for ions and the TIP4P/2005 model for water. The experiments demonstrate the potential transferability and limitations of the Madrid-2019 force field for nitrate and ammonium ions recently developed by our group at different temperatures and add updated information to the reported datasets of TMDs for strong electrolytes. By using the Despretz law, individual ion contributions are extracted for predictive purposes from the experimental values of the shift in the TMD. Interesting findings for the behavior of the shift in the TMD in nitrate salts expose that this property might be particularly challenging for modelization approaches when dealing with polyatomic species.

Substantial breakdown of the hydrogen-bonding network, local density inhomogeneities and fluid-liquid structural transitions in supercritical octanol-1: A molecular dynamics investigation.

Molecular dynamics simulations have been employed to explore the hydrogen-bonding structure and dynamics in supercritical octanol-1 at a near-critical temperature and up to high densities and pressures. A substantial breakdown of the hydrogen-bonding network when going from ambient-liquid to supercritical conditions is revealed. The fraction of the non-hydrogen bonded molecules significantly increases in supercritical octanol-1, and a substantial decrease in the intermittent hydrogen-bond lifetime is observed. This behavior is also reflected on the maximum local density augmentation, which is comparable to the values obtained for non-polar and non-hydrogen bonded fluids. The existence of a structural transition from an inhomogeneous fluid phase to a soft-liquid one at densities higher than 2.0 ρc is also revealed. At higher densities, a significant change in the reorientational relaxation process is observed, reflected on the significant increase in the ratio of the Legendre reorientational times τ1R/τ2R. The latter becomes much higher than the value predicted by the Debye model of diffusive reorientation and the corresponding ratio for ambient liquid octanol-1. The non-polar tail of octanol-1 under supercritical conditions reorients more slowly in comparison with the polar tail. Interestingly, the opposite behavior is observed for the ambient liquid, further verifying the strong effect of the breakdown of the hydrogen bonding network on the properties of supercritical octanol-1. In accordance with the above-mentioned findings, the static dielectric constant of supercritical octanol-1 is very low even at high densities and pressures, comparable to the values obtained for non-polar and non-hydrogen bonded fluids.

Three-dimensional porous carbon-supported Co/Fe bimetallic nanoparticles derived from carboxymethyl cellulose for enhanced supercapacitor electrodes

The exploration of new high-performance, low-cost, and eco-friendly electrode materials is crucial for improving electrochemical performance. In this research, a three-dimensional interconnected porous composite electrode is synthesized, comprising bimetallic oxide of CoFe2O4 and Co3Fe7 alloy with porous carbon derived from carboxymethyl cellulose (CoFe2O4-Co3Fe7@C), through a straightforward high-temperature annealing process. Various characterizations are conducted on the CoFe2O4-Co3Fe7@C composites. The incorporation of CoFe2O4 and Co3Fe7 nanoparticles into the CMC-derived porous carbon enhances electron conduction pathways and reduces internal electrode resistance, resulting in outstanding electrochemical performance. When the CoFe2O4-Co3Fe7@C composite is carbonized at 700 °C with a current density of 0.5 A g−1, its specific capacitance reaches 3405.25 F g−1. At a power density of 321.44 W kg−1, an asymmetric supercapacitor with activated carbon as the positive and negative electrode and CoFe2O4-Co3Fe7@C-700 as the positive electrode has a maximum energy density of 187.59 Wh kg−1. Moreover, after 10,000 cycles, the composite shows 90.05 % cycling stability. This study paves the way for innovation in energy storage technology.

Exploring Oxygen Vacancy Effect in 1D Structural SnIP for CO2 Electro-Reduction to Formate.

1D nanostructures exhibit a large surface area and a short network distance, facilitating electron and ion transport. In this study, a 1D van der Waals material, tin iodide phosphide (SnIP), is synthesized and used as an electrocatalyst for the conversion of CO2 to formate. The electrochemical treatment of SnIP reconstructs it into a web-like structure, dissolves the I and P components, and increases the number of oxygen vacancies. The resulting oxygen vacancies promote the activity of the CO2 reduction reaction (CO2RR), increasing the local pH of the electrode surface and maintaining the oxidative metal site of the catalyst despite the electrochemically reducing environment. This strategy, which stabilizes the oxidation state of the catalyst, also helps to improve the durability of CO2RR. In practice, 1D structured SnIP catalyst exhibits outstanding performance with >92% formate faradaic efficiency (FEformate) at 300mAcm-2, a maximum partial current density for formate of 343mAcm-2, and excellent long-term stability (>100h at 100mAcm-2 with >86% FEformate). This study introduced a method to easily generate oxygen vacancies on the catalyst surface by utilizing 1D materials and a strategy to improve the durability of CO2RR by stabilizing the oxidation state of the catalyst.

Enhanced performance of quasi-solid-state silicon-air batteries through light-assisted anodic reactions

Silicon-air batteries (SABs) offer a promising energy storage solution due to their high theoretical energy density, cost-effectiveness, and environmental friendliness. However, practical applications are hindered by limitations in maximum discharge current density and discharge voltage, stemming from intrinsic electrochemical properties of the silicon (Si) anode and surface oxidation kinetics. This study addressed the low maximum discharge current density of SABs by leveraging the Si semiconductor properties and employing a light-assisted strategy. Introducing light to the silicon anode generates photogenerated electron-hole pairs. Furthermore, introducing light to the Si anode allowed for the generation of photogenerated electron-hole pairs. The resulting holes reacted with OH- ions to form hydroxyl radical (OH), which efficiently oxidized the Si surface, thereby facilitating electrochemical reactions. This enhancement increased the anodic reaction kinetics, thereby enhancing the maximum discharge current density of SABs. Furthermore, through this strategy, light-assisted SABs exhibited significant performance improvements: under 1 sun illumination, maximum discharge current density increased by 50.0 %, discharge voltage by 10.0 %, and power density by 45.0 %. Under 3 suns illuminations, these metrics improved further, with maximum discharge current density increasing by 87.5 %, discharge voltage by 20 %, and power density by 200 %. Additionally, quasi-solid-state SABs (QSSSABs) according to this strategy exhibited versatility across various application scenarios, thereby significantly expanding the practical potential of SABs technology.