Entropy-driven Hydrated Eutectic Electrolytes with Diverse Solvation Configurations for All-Temperature Zn-Ion Batteries.

Batteries always encounter uncontrollable failure or performance decay under extreme temperature environments, which is largely limited by the properties of electrolytes. Herein, an entropy-driven hydrated eutectic electrolyte (HEE) with diverse solvation configurations is proposed to expand the operating temperature range of Zn-ion batteries. The HEE possesses over 40 types of Zn2+ solvation structure with uniform distribution, contributing to its much higher solvation configurational entropy compared to the conventional aqueous counterpart (only 6 types). These effectively promotes its anti-freezing ability under ultralow temperatures, with a high ionic conductivity of 0.42 mS cm-1 even at a low temperature of -40 °C. Moreover, the entropy-driven property can simultaneously enhance the thermal stability under a high temperature over +140 °C. Therefore, the HEE can enable full cells stably working over a wide temperature range of -40~+80 °C, performing over 1500 cycles with 100% capacity retention at -40 °C and 1000 cycles with ~72% capacity retention at +80 °C. This inspiring concept of entropy-driven electrolyte with quantized solvation configurational entropy value has charming potential for designing future special batteries with excellent adaptability towards extreme temperature environments.

Janus interface enables reversible Zn-ion battery by regulating interfacial water structure and crystal-orientation.

To tackle the shortcomings of traditional battery systems, there has been much focus on aqueous Zn-ion batteries due to various advantages. However, they still suffer from poor stability of Zn anodes. Here, a methionine additive with unique Janus properties is proposed to regulate the behavior of the interface between Zn anodes and the electrolyte environment. Systematic characterizations as well as calculations elucidate that the Janus additive is adsorbed on the Zn anode via zincophilic -NH2, changing the structure of the electric double layer and breaking the hydrogen bonding network among H2O molecules through hydrophobic S-CH3. At the same time, it can induce preferential formation of Zn(101) with high reversibility. The above two functions contribute to the dendrite inhibiting ability of Zn anodes. As validated, fabricated Zn//Zn symmetric cells achieve stable cycles of 4500 h, 1165 h, and 318 h at 1, 5 and 10 mA cm-2/mA h cm-2, respectively. Furthermore, Zn//Cu asymmetric cells with an average coulombic efficiency of 98.9% for 2200 stable cycles can be realized. Finally, Zn//MnO2 full cells exhibit 79.9% capacity retention with an ultra-high coulombic efficiency of 99.9% for 1000 cycles, much better than that of the pure Zn(ClO4)2 system, indicating the great potential of this useful strategy in aqueous batteries.

Heat stress induces ferroptosis of porcine Sertoli cells by enhancing CYP2C9-Ras- JNK axis.

Heat stress leads to the accumulation of lipid peroxides in Sertoli cells. Unrestricted lipid peroxidation of catalyzed polyunsaturated fatty acids by Cytochrome P450 (CYP) drive the ferroptosis. However, little is known about the role of CYP cyclooxygenase in heat stress-induced ferroptosis in Sertoli cells. In this study, we investigated the relationship between CYP cyclooxygenase and heat stress-induced ferroptosis in porcine Sertoli cells, as well as whether Ras-JNK signaling is involved in the process. The results showed that heat stress significantly increased the expression of cytochrome P450 cyclooxygenase 2C9 (CYP2C9) and the content of epoxyeicosatrienoic acids (EETs), although there are no significant effect on the expression of cytochrome P450 cyclooxygenase 2J2 (CYP2J2) and cytochrome P450 cyclooxygenase 2C8 (CYP2C8). In addition, heat stress reduced the cell viability, the protein expression level of glutathione peroxidase 4 (GPX4) and Ferritin (all P < 0.01) while increased the level of intracellular reactive oxygen species (ROS) and the protein level of Transferrin receptor 1(TFR1) (both P < 0.01), as well as activating the Ras-JNK signaling pathway. Ferrostatin-1, a ferroptosis-specific inhibitor, reduced ROS levels and the protein level of TFR1 (both P < 0.01), but elevated the cell viability, the protein level of GPX4, and Ferritin (all P < 0.01). Sulfaphenazole, a specific inhibitor of CYP2C9 or two small interfering RNAs targaring CYP2C9 enhanced the cell viability (all P < 0.01), while reduced the content of EETs (all P < 0.01) and inhibited the Ras-JNK signaling and ferroptosis under heat stress. Salirasib, a specific inhibitor of Ras, significantly elevated the cell viability, whereas reduced the level of intracellular ROS and inhibited the phosphorylation of JNK, and alleviated heat stress-induced ferroptosis in porcine Sertoli cells. Notably, there is no effect on the expression of CYP2C9 and the content of EETs. These results indicate that heat stress can induce ferroptosis in Sertoli cells by increasing the expression of CYP2C9 and the content of EETs, which in true activates the Ras-JNK signaling pathway, but there is no feedback from Ras-JNK signaling to the expression of CYP2C9. Our study finds a novel heat stress-induced cell death model of Sertoli cells as well as providing the therapeutic potential for anti-ferroptosis.

Tailoring water structure with high-tetrahedral-entropy for antifreezing electrolytes and energy storage at -80 °C.

One of unsolved puzzles about water lies in how ion-water interplay affects its freezing point. Here, we report the direct link between tetrahedral entropy and the freezing behavior of water in Zn2+-based electrolytes by analyzing experimental spectra and molecular simulation results. A higher tetrahedral entropy leads to lower freezing point, and the freezing temperature is directly related to the entropy value. By tailoring the entropy of water using different anions, we develop an ultralow temperature aqueous polyaniline| |Zn battery that exhibits a high capacity (74.17 mAh g-1) at 1 A g-1 and -80 °C with ~85% capacity retention after 1200 cycles due to the high electrolyte ionic conductivity (1.12 mS cm-1). Moreover, an improved cycling life is achieved with ~100% capacity retention after 5000 cycles at -70 °C. The fabricated battery delivers appreciably enhanced performance in terms of frost resistance and stability. This work serves to provide guidance for the design of ultralow temperature aqueous batteries by precisely tuning the water structure within electrolytes.

Anion-Trap Engineering toward Remarkable Crystallographic Reorientation and Efficient Cation Migration of Zn Ion Batteries.

Zn batteries are considered as potential candidates in future power sources, however suffer problems of rampant dendrite/by-product on Zn anodes, torpid Zn2+ transfer/diffusion and poor energy density. Inspired by the host-guest interaction chemistry, an anion-trap agent ß-cyclodextrin (ß-CD) is introduced into the Zn(ClO4 )2 electrolyte to induce dominant Zn (002) deposition and improve Zn2+ migration behaviors. The anion ClO4 - is revealed to be trapped inside the cavity of ß-CD, impairing barriers for Zn2+ migration and significantly elevating the Zn2+ transference number to 0.878. Meanwhile, the ß-CD@ClO4 - complex shows the function in preferential growth of the Zn (002), blocking the approach of dendrite growth. Above combined functions lead to substantial enhancement in long-term stability and cell capacity, as proved by 10 times longer life of Zn||Zn symmetric cells and 57 % capacity increasement of Zn-MnO2 full cells (at 0.1 A g-1 ) compared with that of pure Zn(ClO4 )2 electrolyte.

Chaotropic Polymer Additive with Ion Transport Tunnel Enable Dendrite-Free Zinc Battery.

Zn batteries are considered the new-generation candidate for large-scale energy storage systems, taking both safety and environmental problems into account. They are still restricted by unexpected dendrite/byproducts occurring on the Zn anodes. We hereby screen a powerful polymer type additive, hyaluronic acid (HA), to regulate the typical ZnSO4 electrolyte for obtaining dendrite-free Zn ion batteries. The intrinsically chaotropic property of the HA molecule can efficiently destruct the original hydrogen-bonds from H2O-H2O, thus restricting the common parasitic reactions derived from the large amount of active water molecules. Simultaneously, the abundant functional groups along the long chain from HA additives can construct an effective tunnel for transferring Zn2+ smoothly, enabling an obviously improved Zn ion transference number of 0.62. Owning to the above intriguing mechanism for regulating the solvation structure of electrolyte systems, the HA additives can greatly increase the cycling life of Zn-Zn symmetric cells to 2200 and 800 h under the conditions of 1 mA cm-2/1 mAh cm-2 and 5 mA cm-2/5 mAh cm-2, respectively. Modified performance for both Zn-Ti and Zn-MnO2 can all be realized by this valid additive, elucidating it can be potentially utilized in large-scale Zn based aqueous energy storage devices.

Manipulating Interfacial Stability Via Absorption-Competition Mechanism for Long-Lifespan Zn Anode.

The stability of Zn anode in various Zn-based energy storage devices is the key problem to be solved. Herein, aromatic aldehyde additives are selected to modulate the interface reactions between the Zn anode and electrolyte. Through comprehensively considering electrochemical measurements, DFT calculations and FEA simulations, novel mechanisms of one kind of aromatic aldehyde, veratraldehyde in inhibiting Zn dendrite/by-products can be obtained. This additive prefers to absorb on the Zn surface than H2O molecules and Zn2+, while competes with hydrogen evolution reaction and Zn plating/stripping process via redox reactions, thus preventing the decomposition of active H2O near the interface and uncontrollable Zn dendrite growth via a synactic absorption-competition mechanism. As a result, Zn-Zn symmetric cells with the veratraldehyde additive realize an excellent cycling life of 3200 h under 1 mA cm-2/1 mAh cm-2 and over 800 h even under 5 mA cm-2/5 mAh cm-2. Moreover, Zn-Ti and Zn-MnO2 cells with the veratraldehyde additive both obtain elevated performance than that with pure ZnSO4 electrolyte. Finally, two more aromatic aldehyde additives are chosen to prove their universality in stabilizing Zn anodes.

Simultaneous Regulation on Solvation Shell and Electrode Interface for Dendrite-Free Zn Ion Batteries Achieved by a Low-Cost Glucose Additive.

Dendrite growth and by-products in Zn metal aqueous batteries have impeded their development as promising energy storage devices. We utilize a low-cost additive, glucose, to modulate the typical ZnSO4 electrolyte system for improving reversible plating/stripping on Zn anode for high-performance Zn ion batteries (ZIBs). Combing experimental characterizations and theoretical calculations, we show that the glucose in ZnSO4 aqueous environment can simultaneously modulate solvation structure of Zn2+ and Zn anode-electrolyte interface. The electrolyte engineering can alternate one H2 O molecule from the primary Zn2+ -6H2 O solvation shell and restraining side reactions due to the decomposition of active water. Concomitantly, glucose molecules are inclined to absorb on the surface of Zn anode, suppressing the random growth of Zn dendrite. As a proof of concept, a symmetric cell and Zn-MnO2 full cell with glucose electrolyte achieve boosted stability than that with pure ZnSO4 electrolyte.

A Flexible Microsupercapacitor with Integral Photocatalytic Fuel Cell for Self-Charging.

With the rapid advancement in different kinds of portable electronics, self-powered systems with small volume and high-performance characteristics have attracted great attention in recent years. It would be rather exciting if one integrated system can not only convert recyclable energy or waste to electricity but also store energy at the same time. Here, flexible all-in-one energy chips composed of urea-based photocatalytic fuel cells (PFCs) and asymmetric microsupercapacitors (AMSCs) are designed on the same plane for powering small portable electronics. The planar PFC consisting of TiO2 photoanode and Ag counter electrode, utilizing urea as fuel, can produce a stable energy output (highest power density of 3.04 µW cm-2 in 1 M urea solution under a UV intensity of 30 mW cm-2) while purify this wasted water simultaneously. Besides, the AMSC comprised of NiCoP@NiOOH positive electrode and zeolite imidazolide framework derived carbon (ZIF-C) negative electrode achieves a high areal capacitance of 54.7 mF cm-2 at 0.5 mA cm-2 and an excellent energy density of 13.9 µWh cm-2 at the power density of 270.5 µW cm-2. Its stability can be confirmed by 86% capacitance retention after 8000 electrochemical cycles and almost no decay after 500 bending cycles. Four PFCs and two AMSCs can be easily constructed into an energy chip and power small electronics. This eco-friendly and self-sustainable system has great potential in future portable electronics.

Hierarchical bi-continuous Pt decorated nanoporous Au-Sn alloy on carbon fiber paper for ascorbic acid, dopamine and uric acid simultaneous sensing.

In this work, Pt nanoparticles modified nanoporous AuSn(Pt@NP-AuSn) alloy on Ni buffered flexible carbon fiber paper (CFP) is fabricated by a simple replacement reaction in which NP-AuSn is fabricated by controllable dealloy of electrodeposited Au-Sn alloy films. The as prepared Pt@NP-AuSn/Ni/CFP possesses hierarchical pore structure, high specific surface area and excellent catalytic activity. Due to the bi-functions of both the large surface area of nanoporous metal and macroporous of carbon fiber paper facilitating mass transfer, the Pt@NP-AuSn/Ni/CFP shows high sensitivity of detecting ascorbic acid (AA), dopamine (DA) and uric acid (UA), with sensitivities of 0.14 µA µM-1 cm-2, 15.23 µA µM-1 cm-2, 0.28 µA µM-1 cm-2 under the concentration ranging from 200 to 2000 µM, 1-10 µM, and 25-800 µM for AA, DA and UA, respectively. Further, the Pt@NP-AuSn/Ni/CFP possesses long-term stability of sensing AA, DA and UA and presents great anti-interference towards a variety of common compounds in body fluid. All of these results manifest the Pt@NP-AuSn/Ni/CFP can be a promising candidate for the application of the electrochemical sensor for simultaneous detection of AA, DA and UA.