Zhiyin Yang

The rising demand for sustainable and scalable energy storage systems has accelerated the development of aqueous zinc‐based technologies. However, conventional slurry‐cast planar electrodes underperform at high mass loading, causing low areal capacitance and sluggish rate performance. Herein, we introduce a 3D printed freestanding, binder‐free conductive carbon lattice electrode integrated with vanadium oxide (VO _x ). The 3D framework facilitates homogeneous dispersion of VO _x , increasing the electroactive surface area, enhancing the ion transport ability, and maintaining structural integrity under high current density. Enabled by this architecture and a high mass loading of 38 mg cm ⁻² , the electrode achieves areal capacitance of 7129 mF cm ⁻² at 3 mA cm ⁻² , areal power and energy densities of 44 mW cm ⁻² and 1 mWh cm ⁻² , along with robust cycling performance, with a capacity retention of 82% after 1500 cycles. To ensure rigorous and reproducible evaluation, we introduce a sealed, 3D‐printed test cell that fixes the inter‐electrode spacing and suppresses electrolyte evaporation. Compared with open beaker setups commonly used for three‐electrode measurements, the printed cell yields more consistent capacitance and resistance. It also maintains 98% capacity retention after 1400 cycles. This synergy of 3D engineered electrodes and cells provides a reproducible pathway to practical, high‐energy, and power‐density zinc‐ion supercapacitors.

The present work details the development of carbon fiber-reinforced epoxy membranes with excellent rejection of small-molecule dyes. It is a proof-of-concept for a more sustainable membrane design incorporating carbon fibers, and their recycling and reuse. 4,4′-methylenebis(cyclohexylamine) (MBCHA) polymerized with either bisphenol-A-diglycidyl ether (BADGE) or tetraphenolethane tetraglycidylether (EPON Resin 1031) in polyethylene glycol (PEG) were used to make monolithic membranes reinforced by nonwoven carbon fibers. Membrane pore sizes were tuned by adjusting the molecular weight of the PEG used in the initial polymerization. Membranes made of BADGE-MBCHA showed rejection of Rose Bengal approaching 100%, while tuning the pore sizes substantially increased the rejection of Methylene Blue from ~65% to nearly 100%. The membrane with the best permselectivity was made of EPON-MBCHA polymerized in PEG 300. It has an average DI flux of 4.48 LMH/bar and an average rejection of 99.6% and 99.8% for Rose Bengal and Methylene Blue dyes, respectively. Degradation in 1.1 M sodium hypochlorite enabled the retrieval of the carbon fiber from the epoxy matrix, suggesting that the monolithic membranes could be recycled to retrieve high-value products rather than downcycled for incineration or used as a lower selectivity membrane. The mechanism for epoxy degradation is hypothesized to be part chemical and part physical due to intense swelling stress leading to erosion that leaves behind undamaged carbon fibers. The retrieved fibers were successfully used to make another membrane exhibiting similar performance to those made with pristine fibers.

Focus on advancement of energy storage has now turned to curbing carbon emissions in the transportation sector by adopting electric vehicles (EVs). Technological advancements in lithium‐ion batteries (LIBs), valued for their lightweight and high capacity, are critical to making this switch a reality. Integrating structurally enhanced LIBs directly into vehicular design tackles two EV limitations: vehicle range and weight. In this study, 3D‐carbon (3D‐C) lattices, prepared with an inexpensive stereolithography‐type 3D printer followed by carbonization, are proposed as scaffolds for Li metal anodes for structural LIBs. Mechanical stability tests revealed that the 3D‐C lattice can withstand a maximum stress of 5.15 ± 0.15 MPa, which makes 3D‐C lattices an ideal candidate for structural battery electrodes. Symmetric cell tests show the superior cycling stability of 3D‐C scaffolds compared to conventional bare Cu foil current collectors. When 3D‐C scaffolds are used, a small overpotential (≈0.075 V) is retained over 100 cycles at 1 mA cm⁻² for 3 mAh cm⁻², while the overpotential of a bare Cu symmetric cell is unstable and increased to 0.74 V at the 96th cycle. The precisely oriented internal pores of the 3D‐C lattice confine lithium metal deposits within the 3D scaffold, effectively preventing short circuits.

We report a novel synthetic approach combining laser-scribing and calcination to make a pseudocapacitive V ₂ O ₅ /laser-scribed graphene composite. The unconventional synthesis gives rise to high-performance.

Silicon has gained significant attention as a lithium‐ion battery anode material due to its high theoretical capacity compared to conventional graphite. Unfortunately, silicon anodes suffer from poor cycling performance caused by their extreme volume change during lithiation and de‐lithiation. Compositing silicon particles with 2D carbon materials, such as graphene, can help mitigate this problem. However, an unaddressed challenge remains: a simple, inexpensive synthesis of Si/graphene composites. Here, a one‐step laser‐scribing method is proposed as a straightforward, rapid (≈3 min), scalable, and less‐energy‐consuming (≈5 W for a few minutes under air) process to prepare Si/laser‐scribed graphene (LSG) composites. In this research, two types of Si particles, Si nanoparticles (SiNPs) and Si microparticles (SiMPs), are used. The rate performance is improved after laser scribing: SiNP/LSG retains 827.6 mAh g⁻¹at 2.0 A g_Si+C⁻¹, while SiNP/GO (before laser scribing) retains only 463.8 mAh g⁻¹. This can be attributed to the fast ion transport within the well‐exfoliated 3D graphene network formed by laser scribing. The cyclability is also improved: SiNP/LSG retains 88.3% capacity after 100 cycles at 2.0 A g_Si+C⁻¹, while SiNP/GO retains only 57.0%. The same trend is found for SiMPs: the SiMP/LSG shows better rate and cycling performance than SiMP/GO composites.

The macroscopic and microscopic interactions between liquid ammonia and graphitic materials are discussed, including dispersion, doping, mechanical testing, and shrinkages.

Sulfonyl-capped laser-converted 3D turbostratic carbon foams enable efficient faradaic reactions, resulting in a 157.6 F g⁻¹ supercapacitor that is stable after 15 000 cycles, comparable to state-of-the-art pseudocapacitors and hybrid capacitors.

Flavonoids are used as natural additives and antioxidants in foods, and after coordination to metal ions, as drug candidates, depending on the flavonoid structure. The rate of radical scavenging of the ubiquitous plant flavonoid kaempferol (3,5,7,4′-tetrahydroxyflavone, Kaem) was found to be significantly enhanced by coordination of Mg(II), Ca(II), Sr(II), and Ba(II) ions, whereas the radical scavenging rate of apigenin (5,7,4′-trihydroxyflavone, Api) was almost unaffected by alkaline earth metal (AEM) ions, as studied for short-lived β-carotene radical cations (β-Car˙⁺) formed by laser flash photolysis in chloroform/ethanol (7 : 3) and for the semi-stable 2,2-diphenyl-1-picrylhydrazyl radical, DPPH˙, in ethanol at 25 °C. A 1 : 1 Mg(II)–Kaem complex was found to be in equilibrium with a 1 : 2 Mg(II)–Kaem₂ complex, while for Ca(II), Sr(II) and Ba(II), only 1 : 2 AEM(II)–Kaem complexes were detected, where all complexes showed 3-hydroxyl and 4-carbonyl coordination and stability constants of higher than 10⁹ L² mol⁻². The 1 : 2 Ca(II)–Kaem₂ complex had the highest second order rate constant for both β-Car˙⁺ (5 × 10⁸ L mol⁻¹ s⁻¹) and DPPH˙ radical (3 × 10⁵ L mol⁻¹ s⁻¹) scavenging, which can be attributed to the optimal combination of the stronger electron withdrawing capability of the (n − 1)d orbital in the heavier AEM ions and their spatially asymmetrical structures in 1 : 2 AEM–Kaem complexes with metal ion coordination of the least steric hindrance of two perpendicular flavone backbones as ligands in the Ca(II) complex, as shown by density functional theory calculations.

Sn(II) binds to kaempferol (HKaem, 3,4′,5,7-tetrahydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) at the 3,4-site forming [Sn(II)(Kaem)₂] complex in ethanol. DPPH^• scavenging efficiency of HKaem is dramatically decreased by SnCl₂ coordination due to formation of acid inhibiting deprotonation of HKaem as ligands and thus reduces the radical scavenging activity of the complex via a sequential proton-loss electron transfer (SPLET) mechanism. Moderate decreases in the radical scavenging of HKaem are observed by Sn(CH₃COO)₂ coordination and by contact between Sn and HKaem, in agreement with the increase in the oxidation potential of the complex compared to HKaem, leading to a decrease in antioxidant efficiency for fruits and vegetables with Sn as package materials.

Luteolin differs as radical scavenger dramatically from apigenin in respond to Cu(II) coordination despite minor structural difference. Coordination of Cu(II) increases radical scavenging efficiency of luteolin especially at low pH, while decreases efficiency of apigenin both at low and higher pH as studied by ABTS•+ radical scavenging. Luteolin forms 1:1 complex with Cu(II) binding to 4-carbonyl and 5- phenol for pH6. Apigenin forms 1:2 complex independent of pH coordinated to 4-carbonyl and 5-hydroxylyl. Cu(II) coordinated to luteolin, as studied by pH-jump stopped-flow, translocates with rate constants of 11.1 ± 0.3 s–1 from 4,5 to 3′,4′ sites and 1.0 ± 0.1 s–1 s–1 from 3′,4′ to 4,5 site independent of Cu(II) concentration, pointing toward dissociation of Cu(II) from an intermediate with two Cu(II) coordinated as rate determining. 3′,4′-catechol is suggested to be a switch for Cu(II) translocation with deprotonation initiating 4,5 to 3′,4′ translocation and protonation initiating 3′,4′ to 4,5 translocation. For di-coordinated apigenin the coordination symmetry balances an electron withdrawl effect of Cu(II) resulting in a decrease of phenol acidity and less radical scavenging efficiency compared to parent apigenin. In contrast, compared with parent luteolin, radical scavenging rate of both 4,5 and 3′,4′ Cu(II) coordinated luteolin is enhanced through increased phenol acidity by electron withdrawl by Cu(II) as confirmed by DFT calculations. Coordination and translocation of Cu(II) is accordingly increasing antioxidant activity of luteolin at pH approaching the physiological level and is discovered as a novel class of natural molecular machinery derived from plant polyphenols, which seems to be of importance for protection against oxidative stress.