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Sulfurized polyacrylonitrile (SPAN) cathodes offer a promising route for improving Li–S batteries by eliminating polysulfide shuttling and enabling stable, high‐rate performance. Here, a comprehensive mechanistic study of SPAN cathodes with varying sulfur content (0–35 wt.%), revealing how structural and electronic factors that govern charge storage is presented. Cyclic voltammetry shows that SPAN exhibits distinct redox features without soluble polysulfides, and that higher sulfur content leads to sharper redox peaks and increased capacity. In situ Raman spectroscopy reveals that electrochemical cycling induces the formation of nanocrystalline sp2 carbon domains and a decline in φ‐Sx species. X‐ray photoelectron spectroscopy shows the presence of stable S– O functionalities, including sulfone and sulfonate groups, which are previously unreported in SPAN. These S–O motifs evolve with cycling and are correlated with SPAN's redox activity. Trasatti analysis demonstrates that SPAN's charge storage is dominated by surface‐controlled (pseudocapacitive) processes, unlike the diffusion‐limited (redox) behavior of elemental sulfur. The pseudocapacitive contribution to the total capacity is found to increase with increasing S content. The redox density of states, gr(μ), is further quantified using electrochemical capacitance spectroscopy through a density functional theory (DFT) inspired approach. The broad and stable gr(μ), enabled by diverse S–O redox sites and the active participation of the carbon backbone, underpins SPAN's pseudocapacitive behavior and superior cycling stability. We report a fundamental mechanism underlying charge storage in sulfurized polyacrylonitrile cathodes. Stable sulfuroxygen groups and a broad redox density of states enable pseudocapacitive behavior distinct from conventional sulfur cathodes. Through combined spectroscopic and electrochemical analysis, this study reveals key structurefunction relationships that advance the design of high‐performance polymer‐based cathodes for lithiumsulfur energy storage systems.

Practical applications of sulfurized polymer (SP) materials in Li–S batteries (LSBs) are often written off due to their low S content (≈35 wt%). Unlike conventional S8/C composite cathodes, SP materials are shown to function as pseudocapacitors with an active carbon backbone using a comprehensive array of tools including in situ Raman and electrochemical impedance spectroscopy. Critical metric analysis of LSBs containing SP materials with an active carbon skeleton shows that SP cathodes with 35 wt% S are suitable for 350 Wh kg−1 target at the cell level if S loading >5 mg cm−2, electrolyte‐to‐sulfur ratio <2 µL mg−1, and negative‐to‐positive ratio <5 can be achieved. Although 3D current collectors can enable such high loadings, they often add excess mass decreasing the total capacity. An “active” carbon nanotube bucky sandwich current collector developed here offsets its excess weight by contributing to the electric double layer capacity. SP cathodes (35 wt% S) with ≈5.5 mg cm−2 of S loading (≈15.8 mg cm−2 of SP loading) yield a sulfur‐level gravimetric capacity ≈1360 mAh gs−1 (≈690 mAh gs−1), electrode level capacity 200 mAh gelectrode−1 (100 mAh gelectrode−1), and areal capacity ≈7.8 mAh cm−2 (≈4.0 mAh cm−2) at 0.1C (1C) rate for ≈100 cycles at E/S ratio = 7 µL mg−1. Beyond elemental sulfur electrodes for LiS batteries, many researchers propose sulfurized polymers (SP) for circumventing polysulfide formation and achieving long cycling stability. The practical application of SP electrodes is often written off due to low S loading. It is shown that N doping in SP electrodes removes quantum capacitance limitations allowing them to function as pseudocapacitors with increased total capacity.

Infrared transmission characteristics of VO2 thin films synthesized on multiple substrates, using a low-pressure direct oxidation technique, have been characterized. Material characterization of these films indicates high material quality, which resulted in large variation of electrical and optical properties at phase transition. A change in optical transmissivity greater than 80% was observed for these films utilizing infrared (IR) laser illumination at 1550 nm. Phase transition enabled by temperature change induced by a pulsed high-power laser beam resulted in modulated IR laser transmission with a low time constant in VO2 on transparent quartz and muscovite substrates. Investigation of the effect of mechanical strain on phase transition in VO2 grown on flexible muscovite substrate indicate shift in transition temperature to higher for tensile and lower for compressive strains.

Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds barium titanate (BaTiO3) and strontium titanate (SrTiO3) nanoparticles as anode materials for lithium-ion batteries from straightforward and standard carbonate-based electrolyte with 10% fluoroethylene carbonate (FEC) additive [1M LiPF6 (1:1 EC: DEC) + 10% FEC]. SrTiO3 and BaTiO3 electrodes can deliver a high specific capacity of 80 mA h g−1 at a safe and low average working potential of ≈0.6 V vs. Li/Li+ with excellent high-rate performance with specific capacity of ~90 mA h g−1 at low current density of 20 mA g−1 and specific capacity of ~80 mA h g−1 for over 500 cycles at high current density of 100 mA g−1. Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li+ ion storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries.

Development in high-rate electrode materials capable of storing vast amounts of charge in a short duration to decrease charging time and increase power in lithium-ion batteries is an important challenge to address. Here, we introduce a synthesis strategy with a series of composition-controlled NMC cathodes, including LiNi0.2Mn0.6Co0.2O2(NMC262), LiNi0.3Mn0.5Co0.2O2(NMC352), and LiNi0.4Mn0.4Co0.2O2(NMC442). A very high-rate performance was achieved for Mn-rich LiNi0.2Mn0.6Co0.2O2 (NMC262). It has a very high initial discharge capacity of 285 mAh g−1 when charged to 4.7 V at a current of 20 mA g−1 and retains the capacity of 201 mAh g−1 after 100 cycles. It also exhibits an excellent rate capability of 138, and 114 mAh g−1 even at rates of 10 and 15 C (1 C = 240 mA g−1). The high discharge capacities and excellent rate capabilities of Mn-rich LiNi0.2Mn0.6Co0.2O2 cathodes could be ascribed to their structural stability, controlled particle size, high surface area, and suppressed phase transformation from layered to spinel phases, due to low cation mixing and the higher oxidation state of manganese. The cathodic and anodic diffusion coefficient of the NMC262 electrode was determined to be around 4.76 × 10−10 cm2 s−1 and 2.1 × 10−10 cm2 s−1, respectively.

Infrared transmission characteristics of VO thin films synthesized on multiple substrates, using a low-pressure direct oxidation technique, have been characterized. Material characterization of these films indicates high material quality, which resulted in large variation of electrical and optical properties at phase transition. A change in optical transmissivity greater than 80% was observed for these films utilizing infrared (IR) laser illumination at 1550 nm. Phase transition enabled by temperature change induced by a pulsed high-power laser beam resulted in modulated IR laser transmission with a low time constant in VO on transparent quartz and muscovite substrates. Investigation of the effect of mechanical strain on phase transition in VO grown on flexible muscovite substrate indicate shift in transition temperature to higher for tensile and lower for compressive strains.

Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds barium titanate (BaTiO[sub.3]) and strontium titanate (SrTiO[sub.3]) nanoparticles as anode materials for lithium-ion batteries from straightforward and standard carbonate-based electrolyte with 10% fluoroethylene carbonate (FEC) additive [1M LiPF[sub.6] (1:1 EC: DEC) + 10% FEC]. SrTiO[sub.3] and BaTiO[sub.3] electrodes can deliver a high specific capacity of 80 mA h g[sup.−1] at a safe and low average working potential of ≈0.6 V vs. Li/Li[sup.+] with excellent high-rate performance with specific capacity of ~90 mA h g[sup.−1] at low current density of 20 mA g[sup.−1] and specific capacity of ~80 mA h g[sup.−1] for over 500 cycles at high current density of 100 mA g[sup.−1]. Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li[sup.+] ion storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries.

Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds barium titanate (BaTiO ) and strontium titanate (SrTiO ) nanoparticles as anode materials for lithium-ion batteries from straightforward and standard carbonate-based electrolyte with 10% fluoroethylene carbonate (FEC) additive [1M LiPF (1:1 EC: DEC) + 10% FEC]. SrTiO and BaTiO electrodes can deliver a high specific capacity of 80 mA h g at a safe and low average working potential of ≈0.6 V vs. Li/Li with excellent high-rate performance with specific capacity of ~90 mA h g at low current density of 20 mA g and specific capacity of ~80 mA h g for over 500 cycles at high current density of 100 mA g . Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li ion storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries.