A self-regulated interface enabled by trivalent gadolinium ions toward highly reversible zinc metal anodes.

Aqueous zinc-ion batteries (AZIBs) have become an ideal candidate for large-scale energy storage systems owing to their inherent safety and highly competitive capacity. However, severe dendrite growth and side reactions on the surface of zinc metal anodes lead to quick performance deterioration, seriously impeding the commercialization of AZIBs. In this work, a self-regulated zinc metal/electrolyte interface is constructed to solve these problems by incorporating the trivalent Gd3+ additive with a lower effective reduction potential into the aqueous ZnSO4 electrolyte. It is revealed that the inert Gd3+ ions preferentially adsorb on the active sites of the zinc anode, and the induced electrostatic shielding layer is beneficial to uniform Zn deposition. Meanwhile, the adsorbed Gd3+ ions act as a buffer interface to lower the direct contact of the zinc anode with water molecules, thereby suppressing the interfacial parasitic reaction. These features endow the Zn//Zn battery using 0.2 M Gd3+ ions with 2940 h of cycling life at 5 mA cm-2 and a cumulative plating capacity (CPC) of 6.2 Ah cm-2 at 40 mA cm-2. When assembling with a MnO2 cathode, the full cell using the modified electrolyte exhibits a high capacity of 268.9 mAh/g at 0.2 A/g, as well as improved rate capability and cycle stability. The results suggest the great potential of a rare earth ion additive in reinforcing Zn metal anodes for developing practical AZIBs.

Spatially contrastive variational autoencoder for deciphering tissue heterogeneity from spatially resolved transcriptomics.

Recent advances in spatially resolved transcriptomics (SRT) have brought ever-increasing opportunities to characterize expression landscape in the context of tissue spatiality. Nevertheless, there still exist multiple challenges to accurately detect spatial functional regions in tissue. Here, we present a novel contrastive learning framework, SPAtially Contrastive variational AutoEncoder (SpaCAE), which contrasts transcriptomic signals of each spot and its spatial neighbors to achieve fine-grained tissue structures detection. By employing a graph embedding variational autoencoder and incorporating a deep contrastive strategy, SpaCAE achieves a balance between spatial local information and global information of expression, enabling effective learning of representations with spatial constraints. Particularly, SpaCAE provides a graph deconvolutional decoder to address the smoothing effect of local spatial structure on expression's self-supervised learning, an aspect often overlooked by current graph neural networks. We demonstrated that SpaCAE could achieve effective performance on SRT data generated from multiple technologies for spatial domains identification and data denoising, making it a remarkable tool to obtain novel insights from SRT studies.

Revealing the Chemical Instability of Mg3Sb2-xBix-Based Thermoelectric Materials.

n-Type Mg3Sb2-xBix alloys have been regarded as promising thermoelectric materials due to their excellent performance and low cost. For practical applications, the thermoelectric performance is not the only factor that should be taken into consideration. In addition, the chemical and thermal stabilities of the thermoelectric material are of equal importance for the module design. Previous studies reported that the Mg3Sb2-xBix alloys were unstable in an ambient environment. In this work, we found that Mg3Sb2-xBix alloys reacted with H2O and O2 at room temperature and formed amorphous Mg(OH)2/MgO and crystalline Bi/Sb. The substantial loss of Mg resulted in a significant deterioration in thermoelectric properties, accompanied by the transition from n-type to p-type. With the increase in Bi content, the chemical stability decreased due to the higher formation energy of Mg3Bi2. A chemically stable Mg3Bi2 sample was achieved by coating it with polydimethylsiloxane to isolate H2O and O2 in the air.

Characterizing the thermoelectric cooling performance across a broad temperature range.

Thermoelectric cooling plays an essential role in precisely controlling the temperature of electronics. Characterizing the performance of thermoelectric coolers (TECs) is of great significance for the development of advanced solid-state cooling devices. However, the existing setup for characterizing the cooling performance of TECs has mainly been limited to the near room temperature range. Herein, we report the development of a new setup that is capable of characterizing thermoelectric cooling performance across a broad temperature range (80-350 K). With precise and steady control of the hot-side temperature, measurements of the coefficient of performance and maximum temperature difference at room temperature have been conducted on commercial devices. By comparing the results with the commercial datasheet, it shows that our setup can accurately evaluate the cooling performance of thermoelectric devices. In addition, we further extend the characterization to different hot-side temperatures, e.g., 173, 325, and 350 K, thus demonstrating the capability of our setup for evaluating the thermoelectric performance across a broad temperature range.

Nitrate Radical Induced "Two in One" Interface Engineering toward High Reversibility of Zn Metal Anode.

Advanced interfacial engineering performs a forceful modulation effect on Zn2+ plating/stripping with simultaneous inhibition of hydrogen evolution reaction, chemical corrosion, and dendrite growth, which is responsible for high reversibility of Zn anode. Herein, a "two in one" interface engineering is developed to improve the reversibility of Zn anode, in which multi-functional Zn5 (NO3 )2 (OH)8 ·2H2 O layer and preferential Zn (002) texture are constructed simultaneously. Due to nucleophilicity to Zn2+ arising from electronegativity, the layer can accelerate the desolvation process of [Zn (H2 O)6 ]2+ and transfer kinetics of Zn2+ ions, leading to uniform nucleation and effective inhibition of water-induced side reactions. Meanwhile, the latter is beneficial to guiding   Zn (002)-preferred orientation deposition with compact structure. Consequently, the Zn electrodes with such complementary interface modulation exhibit prominent reversibility. With an area capacity of 1 mAh cm-2 at 1 mA cm-2 , the symmetric cell operates steadily for 4000 h. Highly reversible Zn anode is maintained even at 50 mA cm-2 . For full cells coupled with MnO2 cathode, impressive rate capability and cycling stability with a high capacity beyond 100 mAh g-1 at 1 A g-1 after 2000 cycles are achieved. The results provide new insights into Zn anodes with high reversibility for next-generation aqueous zinc ion batteries.

Multiscale Structural Engineering of Sulfur/Carbon Cathodes Enables High Performance All-Solid-State LiS Batteries.

Constructing all-solid-state lithium-sulfur batteries (ASSLSBs) cathodes with efficient charge transport and mechanical flexibility is challenging but critical for the practical applications of ASSLSBs. Herein, a multiscale structural engineering of sulfur/carbon composites is reported, where ultrasmall sulfur nanocrystals are homogeneously anchored on the two sides of graphene layers with strong SC bonds (denoted as S@EG) in chunky expanded graphite particles via vapor deposition method. After mixing with Li9.54 Si1.74 P1.44 S11.7 Cl0.3 (LSPSCL) solid electrolytes (SEs), the fabricated S@EG-LSPSCL cathode with interconnected "Bacon and cheese sandwich" feature can simultaneously enhance electrochemical reactivity, charge transport, and chemomechanical stability due to the synergistic atomic, nanoscopic and microscopic structural engineering. The assembled InLi/LSPSCL/S@EG-LSPSCL ASSLSBs demonstrate ultralong cycling stability over 2400 cycles with 100% capacity retention at 1 C, and a record-high areal capacity of 14.0 mAh cm-2 at a record-breaking sulfur loading of 8.9 mg cm-2 at room temperature as well as high capacities with capacity retentions of ≈100% after 600 cycles at 0 and 60 °C. Multiscale structural engineered sulfur/carbon cathode has great potential to enable high-performance ASSLSBs for energy storage applications.

Gender congruence and mental health problems among Chinese transgender and gender non-conforming individuals: A process model involving rumination and stigma consciousness.

OBJECTIVE: The present study examined the roles of gender identity rumination and stigma consciousness in the relationship between gender congruence (comfort with one's gender identity and external appearance) and mental health problems (anxiety and depression). METHODS: Three hundred and fourteen Chinese individuals identified as transgender and gender non-conforming (TGNC) individuals were recruited through the Internet and answered an online questionnaire (Mage = 24.34 years, standard deviation = 5.80). RESULTS: Gender congruence was associated with anxiety and depression through three indirect pathways: rumination, stigma consciousness, and sequentially through rumination and stigma consciousness. CONCLUSION: Gender congruence is an intrapersonal resource that reduces mental health problems through its positive impacts on the TGNC identity process. A more consistent feeling of gender, a lower level of rumination, and a reduced level of consciousness about stigma could be potential working points for interventions in the TGNC community to help alleviate their mental health problems.

Ultra-low thermal conductivity and high thermoelectric performance of monolayer BiP3: a first principles study.

The thermoelectric properties of monolayer triphosphide BiP3 are studied via first principles calculations and Boltzmann transport equation. First, the Seebeck coefficient, electrical conductivity and electron thermal conductivity at different temperatures are calculated using the Boltzmann transport equation with relaxation time approximation. It has been observed that BiP3 has a large power factor (265 × 10-4 W K-2 m-1, 700 K). Then, by analyzing the second-order interatomic force constant (IFCS), the atomic structure and phonon dispersion were studied, and the thermal conductivity of monolayer BiP3 was predicted in the temperature range of 300-800 K, and it was found that it had a very low thermal conductivity (2.13 W m-1 K-1) at room temperature. The thermal conductivity is mainly contributed by the branches of acoustics along in-plane transverse (TA). Finally, the maximum ZT value of monolayer BiP3 is 3.06 at 700 K, when the electron doping concentration is 2.35 × 1011 cm-2, which indicates that it is a promising thermoelectric material.

The Thermoelectric Properties of Monolayer MAs2 (M = Ni, Pd and Pt) from First-Principles Calculations.

The thermoelectric property of the monolayer MAs2 (M = Ni, Pd and Pt) is predicted based on first principles calculations, while combining with the Boltzmann transport theory to confirm the influence of phonon and electricity transport property on the thermoelectric performance. More specifically, on the basis of stable geometry structure, the lower lattice thermal conductivity of the monolayer NiAs2, PdAs2 and PtAs2 is obtained corresponding to 5.9, 2.9 and 3.6 W/mK. Furthermore, the results indicate that the monolayer MAs2 have moderate direct bang-gap, in which the monolayer PdAs2 can reach 0.8 eV. The Seebeck coefficient, power factor and thermoelectric figure of merit (ZT) were calculated at 300, 500 and 700 K by performing the Boltzmann transport equation and the relaxation time approximation. Among them, we can affirm that the monolayer PdAs2 possesses the maximum ZT of about 2.1, which is derived from a very large power factor of 3.9 × 1011 W/K2ms and lower thermal conductivity of 1.4 W/mK at 700 K. The monolayer MAs2 can be a promising candidate for application at thermoelectric materials.

KAgX (X = S, Se): High-Performance Layered Thermoelectric Materials for Medium-Temperature Applications.

Monolayer KAgX are a class of novel two-dimensional (2D) layered materials with efficient optical absorption and superior carrier mobility, signifying their potential application prospect in photovoltaic (PV) and thermoelectric (TE) fields. Motivated by the recent theoretical studies on the KAgX monolayer, we carried out systematic investigations on the TE performance of KAgS and KAgSe monolayers, employing density functional theory (DFT) and semiclassical Boltzmann transport equation (BTE). For both KAgSe and KAgS monolayers, large Grüneisen parameters, low group velocities, and short phonon scattering time greatly hinder their heat transport and result in an ultralow thermal conductivity, 0.26 and 0.33 W m-1 K-1 at 300 K, respectively. A twofold degeneracy appearing at the Γ point and the abrupt slope of the density of states (DOS) near the Fermi level give rise to high Seebeck coefficients of KAgX monolayers. Due to the ultralow thermal conductivity and excellent electronic transport performance, the ZT values as high as 4.65 (3.11) and 4.05 (2.63) at 500 (300) K in the n-type doping for KAgSe and KAgS monolayers are obtained. The exceptional performance of KAgX monolayers sheds light on their immense potential applications in the medium-temperature (around 300-500 K) thermoelectric devices and greatly stimulates further experimental synthesis and validation.