Co-delivery of drugs by adhesive transdermal patches equipped with dissolving microneedles for the treatment of rheumatoid arthritis.

In this study, a dosage form consisting of dissolving (D) microneedles (M) and an adhesive (A) transdermal patch (P; DMAP) was designed and pre-clinically evaluated for the treatment of rheumatoid arthritis (RA). The tip of the dissolving microneedles (DMNs) was loaded with the macromolecular drug melittin (Mel@DMNs), this to treat joint inflammation and bone damage, while the adhesive transdermal patches contained the low molecular weight drug diclofenac sodium (DS; DS@AP) for pain relief. Mel@DMNs and DS@AP were ingeniously connected through an isolation layer for compounding Mel-DS@DMAP for the simultaneous delivery of the drugs. In vitro and in vivo experiments showed that DS@AP did not affect the mechanical properties and dissolution process of Mel@DMNs while the pores formed by the microneedles promoted the skin penetration of DS. Treatment of rats suffering from RA with Mel-DS@DMAP reduced paw swelling and damage of the synovium, joint and cartilage, suggesting that the 'patch-microneedle' dosage form might be promising for the treatment and management of RA.

From Porphyrin-Like Rings to High-Density Single-Atom Catalytic Sites: Unveiling the Superiority of p-C2N for Bifunctional Oxygen Electrocatalysis.

With effective utilization of the catalytic site, single-atom catalysts (SACs) supported by nitrogen atoms surrounding built-in pores of two-dimensional (2D) materials, such as porphyrin/phthalocyanine-based covalent organic frameworks, have been highly promising electrocatalysts in the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) processes for the air electrode of the metal-air battery. However, the number of stable single-atom anchoring sites, i.e., accessible single-atom metal sites, has been concerning as a result of the appearance of heterogeneous or large and even supersized pores in substrate materials. 2D porous graphitic carbon nitride (PGCN) with a stronger stability and smaller component is regarded as a more potential alternative owing to similar controllability and designability. In this work, inspired by the robust coordinated TM-N4 environment of porphyrin/phthalocyanine molecules, novel p-C2N with a high density of porphyrin-like organic units is rationally designed. In well-designed p-C2N, a higher homogeneity and uniformity of coordination sites can enhance the electrocatalytic activity in the whole catalytic material and better prevent SACs from sintering and agglomerating into thermodynamically stable nanoclusters. Utilizing density functional theory (DFT), the stability of the p-C2N monolayer, TM@p-C2N, and OER/ORR catalytic activities of TM@p-C2N (TM including Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, and Au) are systematically evaluated. Among them, Ir@p-C2N (0.31 V of the OER and 0.36 V of the ORR), Co@p-C2N (0.47 and 0.22 V), and Rh@p-C2N (0.55 and 0.27 V) are screened as promising SACs for the bifunctional ORR and OER. The proposal of p-C2N guides a new direction for the development of TM-N-C-based SAC bifunctional electrocatalysts.

Memristor-Based Artificial Chips.

Memristors, promising nanoelectronic devices with in-memory resistive switching behavior that is assembled with a physically integrated core processing unit (CPU) and memory unit and even possesses highly possible multistate electrical behavior, could avoid the von Neumann bottleneck of traditional computing devices and show a highly efficient ability of parallel computation and high information storage. These advantages position them as potential candidates for future data-centric computing requirements and add remarkable vigor to the research of next-generation artificial intelligence (AI) systems, particularly those that involve brain-like intelligence applications. This work provides an overview of the evolution of memristor-based devices, from their initial use in creating artificial synapses and neural networks to their application in developing advanced AI systems and brain-like chips. It offers a broad perspective of the key device primitives enabling their special applications from the view of materials, nanostructure, and mechanism models. We highlight these demonstrations of memristor-based nanoelectronic devices that have potential for use in the field of brain-like AI, point out the existing challenges of memristor-based nanodevices toward brain-like chips, and propose the guiding principle and promising outlook for future device promotion and system optimization in the biomedical AI field.

Evaluating the Effect of Artificial Liver Support on Acute-on-Chronic Liver Failure Using the Quantitative Difference Algorithm: Retrospective Study.

BACKGROUND: Liver failure, including acute-on-chronic liver failure (ACLF), occurs mainly in young adults and is associated with high mortality and resource costs. The prognosis evaluation is a crucial part of the ACLF treatment process and should run through the entire diagnosis process. As a recently proposed novel algorithm, the quantitative difference (QD) algorithm holds promise for enhancing the prognosis evaluation of ACLF. OBJECTIVE: This study aims to examine whether the QD algorithm exhibits comparable or superior performance compared to the Model for End-Stage Liver Disease (MELD) in the context of prognosis evaluation. METHODS: A total of 27 patients with ACLF were categorized into 2 groups based on their treatment preferences: the conventional treatment (n=12) and the double plasma molecular absorption system (DPMAS) with conventional treatment (n=15) groups. The prognosis evaluation was performed by the MELD and QD scoring systems. RESULTS: A significant reduction was observed in alanine aminotransferase (P=.02), aspartate aminotransferase (P<.001), and conjugated bilirubin (P=.002), both in P values and QD value (Lτ>1.69). A significant decrease in hemoglobin (P=.01), red blood cell count (P=.01), and total bilirubin (P=.02) was observed in the DPMAS group, but this decrease was not observed in QD (Lτ≤1.69). Furthermore, there was a significant association between MELD and QD values (P<.001). Significant differences were observed between groups based on patients' treatment outcomes. Additionally, the QD algorithm can also demonstrate improvements in patient fatigue. DPMAS can reduce alanine aminotransferase, aspartate aminotransferase, and unconjugated bilirubin. CONCLUSIONS: As a dynamic algorithm, the QD scoring system can evaluate the therapeutic effects in patients with ACLF, similar to MELD. Nevertheless, the QD scoring system surpasses the MELD by incorporating a broader range of indicators and considering patient variability.

Penta-MP5 (M = B, Al, Ga, In) monolayers as high-performance photocatalysts for overall water splitting.

Two-dimensional (2D) phosphorus-rich phosphides generally preserve the excellent electronic properties of phosphorene, making them promising photocatalysts for water splitting. Despite tremendous efforts in the search for potential photocatalysts in 2D phosphides, few known 2D phosphides fully meet the requirements for photocatalytic water splitting. Herein, we systemically investigate a set of penta-MP5 (M = B, Al, Ga, and In) monolayers by first-principles calculations and identify them as potential photocatalysts for water splitting. These penta-MP5 monolayers are found to feature favorable bandgaps of about 2.70 eV with appropriate band edge positions, a high carrier mobility of 1 × 104 cm-2 V-1 s-1, an excellent optical absorption coefficient (OAC) of 1 × 105 cm-1, and a good solar-to-hydrogen (STH) efficiency of 8%. Meanwhile, free energy calculations indicate that these penta-MP5 monolayers present both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) photocatalytic activities under light conditions. All these excellent properties demonstrate that penta-MP5 monolayers are suitable candidates as photocatalysts for promising applications in overall water splitting.

C3N2: the missing part of highly stable porous graphitic carbon nitride semiconductors.

Two-dimensional (2D) porous graphitic carbon nitrides (PGCNs) with semiconducting features have attracted wide attention because of built-in pores with various active sites, large surface area, and high physicochemical stability. However, only a few PGCNs have been synthesized, covering a 1.23-3.18 eV band gap. We systematically investigate two new 2D PGCN monolayers, T-C3N2 and H-C3N2, including possible pathways for their experimental synthesis. Based on first-principles calculations, the mechanical, electronic, and optical properties of T-C3N2 and H-C3N2 have been systematically investigated. These two architectural frameworks exhibit contrasting mechanical characteristics owing to their structural differences. Both T-C3N2 and H-C3N2 monolayers are predicted to be intrinsic semiconductors. Exceptionally, the stacking bilayers of T-C3N2 can transform into a rare 2D nodal-line semimetal structure. The narrow bandgap (0.35 eV) of the T-C3N2 monolayer and its extraordinary transformation in the bilayer electronic structure fill the vacancy of PGCNs as electronic devices in the middle/long wave infrared region. C3N2 structures possess ultrahigh anisotropic carrier mobilities (×104 cm2 V-1 s-1) and exceptional absorption coefficients (×105 cm-1) in the near-infrared and visible light regions, suggesting its possible optoelectronic applications. The findings expand the scope of 2D PGCNs and offer guides for their experimental realization.

A semiconductor Sc2S3 monolayer with ultrahigh carrier mobility for UV blocking filter application.

For humans, ultraviolet (UV) light from sun is harmful to our eyes and eye-related cells. This detrimental fact requires scientists to search for a material that can efficiently absorb UV light while allowing lossless transmission of visible light. Using an unbiased first-principles swarm intelligence structure search, we explored two-dimensional (2D) Sc-S crystals and identified a novel Sc2S3 monolayer with good thermal and dynamical stability. The optoelectronic property simulations revealed that the Sc2S3 monolayer has a wide indirect bandgap (3.05 eV) and possesses an ultrahigh carrier mobility (2.8 × 103 cm2 V-1 s-1). Remarkably, it has almost transparent visible light absorption, while it exhibits an ultrahigh absorption coefficient up to × 105 cm-1 in the ultraviolet region. Via the application of biaxial strain and thickness modulation, the UV light absorption coefficients of Sc2S3 can be further improved. These findings manifest an attractive UV blocking optoelectronic characteristic of the Sc2S3 configuration as a prototypical nanomaterial for the potential application in UV blocking filters.

Novel Boron-rich Phosphides with High Hardness, Large Strain, and Magnetism.

Boron-rich compounds have attracted much attention due to their interesting structures and excellent properties. Here, we performed an extensive study on the different B-P stoichiometries under pressure by combining a particle swarm optimization method with first-principles calculations. At 1 atm, BP and B6P are thermodynamically stable, while other stoichiometries are metastable. Under pressure, BP and B6P remain stable relative to constituent pure solids up to 80 GPa, while other stoichiometries become unstable at relatively low pressures. A new Cmca B6P is predicted with the lowest energy at 1 atm and shows higher shear strain than the R3̅m structure, which is known to be more resistant to brittle fracture than B4C. Moreover, the predicted Pm B8P is a magnetic semiconductor with a magnetic moment of 1 µB. All these boron-rich phosphides are hard materials. The present results enrich the B-P phase diagram and promote extensive research on their excellent properties.

In-Depth Physical Mechanism Analysis and Wearable Applications of HfOx-Based Flexible Memristors.

Since memristors as an emerging nonlinear electronic component have been considered the most promising candidate for integrating nonvolatile memory and advanced computing technology, the in-depth reveal of the memristive mechanism and the realization of hardware fabrication have facilitated their wide applications in next-generation artificial intelligence. Flexible memristors have shown great promising prospects in wearable electronics and artificial electronic skin (e-skin), but in-depth research on the physical mechanism is still lacking. Here, a flexible memristive device with a Ag/HfOx/Ti/PET crossbar structure was fabricated, and a remarkable analog switching characteristic similar to synaptic behavior was observed. Through detailed data fitting and in-depth physical mechanism analysis, it is confirmed that the analog switching characteristics of the device are mainly caused by carrier tunneling. Furthermore, the memristive properties of the Ag/HfOx/Ag/PET device can be attributed to the conductive filaments formed by the redox reaction of the active metal Ag. Finally, the interfacial barrier is extracted by the Arrhenius diagram and the energy band diagram, which is drawn to clearly demonstrate the conduction mechanism of charge trapping in the device. Therefore, the HfOx-based flexible memristor with analog switching behavior and stable memory performance lays the foundation for cutting-edge applications in wearable electronics and smart e-skin.

A new phosphorene allotrope: the assembly of phosphorene nanoribbons and chains.

Phosphorene allotrope monolayers such as blue and red phosphorus are being designed and synthesized to be used in the optoelectronics field due to their tunable bandgap and high mobility. Using the organic molecule self-assembly method similar to the synthesis of graphene allotropes, a novel phosphorene allotrope, P567 monolayer, with five-, six-, and seven-membered rings is designed through the assembly of black phosphorus chains and blue phosphorene nanoribbons. Ab initio molecular dynamics, phonon dispersion, and elastic constants demonstrate the dynamic, thermal, and mechanical stability of the P567 monolayer. Additionally, the first-principles calculations show that the P567 monolayer is an indirect bandgap semiconductor with moderate bandgap and high anisotropic mobility (4.47 × 103 cm2 V-1 s-1). Compared with black phosphorene, the suitable band edge position and higher optical absorption coefficient (105 cm-1) make the P567 monolayer more likely to be used as a photocatalytic hydrolysis material. The P567 monolayer is a viable candidate for use in innovative optoelectronic devices and the assembly method provides a rational approach to designing phosphorus allotropes with high photocatalytic efficiency.

Mechanical properties of 2D Zrn+1Cn(n= 1, 2) MXenes with and without functionalization.

Transition metal carbides and nitrides (MXenes) are considered the new generation of flexible electronic materials because of their superior mechanical strength and flexibility. Based on the density functional theory, the structures, electronic properties and mechanical properties of the 2D Zr-based MXenes with and without surface functional groups (O, F and OH) are investigated systematically to explore their elastic properties and tensile fracture mechanism. The results reveal the tensile strength and critical strain under biaxial tensile direction can reach 52 GPa, 12% for Zr2C and 55 GPa, 19% for Zr3C2, more outstanding than the mechanical behavior of the pristine Ti2C (47 GPa, 9.5%). The tensile behaviors of the functionalized Zrn+1CnT2(n= 1, 2, T = O, F, OH) strongly depend on the crystallographic orientation and the surface functional group. The phonon spectrum under the critical strain indicates the tensile fracture of the pristine Zr-based MXenes was determined by phonon instability, except along the armchair direction of Zr2C and zigzag direction of Zr3C2. During tensile strain, the collapse of Zrn+1CnF2and Zrn+1Cn(OH)2(n= 1, 2) are mainly caused by internal Zr-C bond rupture and transfer to the surface. While the O-functionalized Zrn+1CnO2(n= 1, 2) presented the opposite collapse trend. Additionally, according to the research results of critical strain, elastic modulus and electrical conductivity, F/OH-terminated Zr2C MXene is relatively more suitable for flexible sensors of wearable devices than Zr3C2T2.

Unveiling Interstitial Anionic Electron-Driven Ultrahigh K-Ion Storage Capacity in a Novel Two-Dimensional Electride Exemplified by Sc3Si2.

Two-dimensional (2D) electrides, characterized by excess interstitial anionic electron (IAE) in a crystalline 2D material, offer promising opportunities for the development of electrode materials, in particular in rechargeable metal-ion batteries applications. Although a few such potential electride materials have been reported, they generally show low metal-ion storage capacity, and the effect of IAE on the ion storage performance remains elusive so far. Here we report a novel 2D electride, [Sc3Si2]1+·1e-, with fascinating IAE-driven high alkali metal-ion storage capacity. In particular, its K-ion specific capacity can reach up to 1497 mA h g-1, higher than any previously reported 2D materials-based anodes in K-ion batteries (PIBs). The IAE in the [Sc3Si2]1+·1e- crystal accounts for such high capacity behavior, which can drift away and balance the charge on the metal-cation, playing a crucial role in stabilizing the metal-ion adsorption and enhancing multilayer-ions adsorption. This proposed IAE-driven storage mechanism provides an unprecedented avenue for the future design of high storage capacity electrode materials.

A novel all-nitrogen molecular crystal N16 as a promising high-energy-density material.

All-nitrogen solids, if successfully synthesized, are ideal high-energy-density materials because they store a great amount of energy and produce only harmless N2 gas upon decomposition. Currently, the only method to obtain all-nitrogen solids is to apply high pressure to N2 crystals. However, products such as cg-N tend to decompose upon releasing the pressure. Compared to covalent solids, molecular crystals are more likely to remain stable during decompression because they can relax the strain by increasing the intermolecular distances. The challenge of such a route is to find a molecular crystal that can attain a favorable phase under elevated pressure. In this work, we show, by designing a novel N16 molecule (tripentazolylamine) and examining its crystal structures under a series of pressures, that the aromatic units and high molecular symmetry are the key factors to achieving an all-nitrogen molecular crystal. Density functional calculations and structural studies reveal that this new all-nitrogen molecular crystal exhibits a particularly slow enthalpy increase with pressure due to the highly efficient crystal packing of its highly symmetric molecules. Vibration mode calculations and molecular dynamics (MD) simulations show that N16 crystals are metastable at ambient pressure and could remain inactive up to 400 K. The initial reaction steps of the decomposition are calculated by following the pathway of the concerted excision of N2 from the N5 group as revealed by the MD simulations.

Ultrahigh oxygen evolution reaction activity in Au doped co-based nanosheets.

Oxygen evolution reaction (OER) has attracted enormous interest as a key process for water electrolysis over the past years. The advance of this process relies on an effective catalyst. Herein, we employed single-atom Au doped Co-based nanosheets (NSs) to theoretically and experimentally evaluate the OER activity and also the interaction between Co and Au. We reveal that Au-Co(OH)2 NSs achieved a low overpotential of 0.26 V at 10 mA cm-2. This extraordinary phenomenon presents an overall superior performance greater than state-of-the-art Co-based catalysts in a sequence of α-Co(OH)2 < Co3O4 < CoOOH < Au-Co(OH)2. With ab initio calculations and analysis in the specific Au-Co(OH)2 configuration, we reveal that OER on highly active Au-Co(OH)2 originates from lattice oxygen, which is different from the conventional adsorbate evolution scheme. Explicitly, the configuration of Au-Co(OH)2 gives rise to oxygen non-bonding (ONB) states and oxygen holes, allowing direct O-O bond formation by a couple of oxidized oxygen with oxygen holes, offering a high OER activity. This study provides new insights for elucidating the origins of activity and synthesizing efficient OER electrocatalysts.

Exploring a novel two-dimensional metallic Y4C3 sheet applied as an anode material for sodium-ion batteries.

As novel "post lithium-ion batteries" and promising alternatives to lithium-ion batteries (LIBs) suffering from the limited Li resources, sodium-ion batteries (SIBs) are nowadays emerging and show bright prospects in large-scale energy storage applications due to abundant Na resources. However, a lack of suitable anode materials has become a key obstacle for the development of SIBs. Here we explore the potential of the two-dimensional (2D) Y-C space and identify a novel anode material for SIBs, a new Y4C3 sheet with P3̄m1 crystal symmetry, by means of first-principles swarm structure calculations. This Y4C3P3̄m1 structure has rather good kinetic and thermodynamic stability, possesses intrinsic metallicity, and remains metallic after adsorbing Na atoms, ensuring good electrical conductivity during the SIB cycle. Remarkably, a Y4C3 sheet as an anode for SIBs possesses the essential properties of a high specific capacity (∼752 mA h g-1), a low barrier energy (∼0.1 eV), and suitable open-circuit voltage (0-0.15 V). These characteristics are comparable and even superior to those of another known 2D Y2C anode material, indicating that the Y4C3 sheet can act as an appealing new candidate as an anode material for SIBs and offering new insights into the 2D Y-C space.

Transition Metal and N Doping on AlP Monolayers for Bifunctional Oxygen Electrocatalysts: Density Functional Theory Study Assisted by Machine Learning Description.

It is vital to search for highly efficient bifunctional oxygen evolution/reduction reaction (OER/ORR) electrocatalysts for sustainable and renewable clean energy. Herein, we propose a single transition-metal (TM)-based defective AlP system to validate bifunctional oxygen electrocatalysis by using the density functional theory (DFT) method. We found that the catalytic activity is enhanced by substituting two P atoms with two N atoms in the Al vacancy of the TM-anchored AlP monolayer. Specifically, the overpotential of OER(ORR) in Co- and Ni-based defective AlP systems is found to be 0.38 (0.25 V) and 0.23 V (0.39 V), respectively, showing excellent bifunctional catalytic performance. The results are further presented by establishing the volcano plots and contour maps according to the scaling relation of the Gibbs free-energy change of *OH, *O, and *OOH intermediates. The d-band center and the product of the number of d-orbital electrons and electronegativity of the TM atom are the ideal descriptors for this system. To investigate the activity origin of the OER/ORR process, we performed the machine learning (ML) algorithm. The result indicates that the number of TM-d electrons (Ne), the radius of TM atoms (rd), and the charge transfer of TM atoms (Qe) are the three primary descriptors characterizing the adsorption behavior. Our results can provide a theoretical guidance for designing highly efficient bifunctional electrocatalysts and pave a way for the DFT-ML hybrid method in catalysis research.

Novel two-dimensional beta-XTe (X = Ge, Sn, Pb) as promising room-temperature thermoelectrics.

In this paper, we designed novel low-symmetry two-dimensional (2D) structures based on conventional XTe (X = Ge, Sn, Pb) thermoelectrics with large average atomic mass. The first-principles calculations combined with Boltzmann transport theory show that the beta-XTe exhibit good stability, high electron carrier mobility, and ultralow ΚL. The subsequent analyses show that the ultralow ΚL stems from the coexistence of resonant bonding, weak bonding, and lone-pair electrons in beta-XTe, which leads to large anharmonicities. On the other hand, the lowest energy conduction band of beta-GeTe and beta-SnTe show the convergence of the low-lying Æ© band, which is the source of the high-power factor in the two systems. The calculated maximum ZT of beta-XTe (X = Ge, Sn, Pb) are 3.08, 1.60, and 0.57 at 300 K, respectively, which is significantly greater than that of the previously reported high-symmetry 2D alpha-XTe and the commercial thermoelectrics. We hope that this work can provide important guidance for the development of thermoelectric materials.

The thermoelectric properties of α-XP (X = Sb and Bi) monolayers from first-principles calculations.

Thermoelectric (TE) materials as one of the effective solutions to the energy crisis are gaining more and more interest owing to their capability to generate electricity from waste heat without generating air pollution. In this work, the TE properties of α-XP monolayers such as the stability, electronic structure, electrical and phonon transport were thoroughly studied in combination with the first-principles calculations and Boltzmann transport equations. We found that α-SbP and α-BiP have indirect bandgaps of 0.85 eV and 0.73 eV, respectively, which are suitable for thermoelectric materials. Furthermore, due to the multiple valleys at the energy band edges and the high carrier mobility, α-XP possesses both large Seebeck coefficients and high electrical conductivities. It is also found that the lattice thermal conductivity of α-BiP is smaller than that of α-SbP due to lower phonon frequencies, smaller phonon group velocities, larger Grüneisen parameters and higher phonon relaxation times. High TE performance was achieved with the ZT values reaching 4.59 (for α-BiP at 500 K) and 1.34 (for α-SbP at 700 K). Our results quantify α-XP monolayers as promising candidates for building outstanding thermoelectric devices.

ABO3 multiferroic perovskite materials for memristive memory and neuromorphic computing.

The unique electron spin, transfer, polarization and magnetoelectric coupling characteristics of ABO3 multiferroic perovskite materials make them promising candidates for application in multifunctional nanoelectronic devices. Reversible ferroelectric polarization, controllable defect concentration and domain wall movement originated from the ABO3 multiferroic perovskite materials promotes its memristive effect, which further highlights data storage, information processing and neuromorphic computing in diverse artificial intelligence applications. In particular, ion doping, electrode selection, and interface modulation have been demonstrated in ABO3-based memristive devices for ultrahigh data storage, ultrafast information processing, and efficient neuromorphic computing. These approaches presented today including controlling the dopant in the active layer, altering the oxygen vacancy distribution, modulating the diffusion depth of ions, and constructing the interface-dependent band structure were believed to be efficient methods for obtaining unique resistive switching (RS) behavior for various applications. In this review, internal physical dynamics, preparation technologies, and modulation methods are systemically examined as well as the progress, challenges, and possible solutions are proposed for next generation emerging ABO3-based memristive application in artificial intelligence.

Promising thermoelectric candidate based on a CaAs3 monolayer: A first principles study.

The CaAs3 monolayer is a newly predicted two-dimensional material with attractive properties, such as a moderate direct bandgap, high carrier mobility, prominent visible-light absorption, etc. To evaluate its potential applications in thermoelectric (TE) fields, herein, the thermoelectric properties of CaAs3 monolayers were comprehensively investigated by a first-principles method in combination with Boltzmann transport theory. Our calculated results indicate that the CaAs3 monolayer has an exceptionally low lattice thermal conductivity of 0.44 W m-1 K-1 at 300 K, mainly because of the small group velocity and strong phonon-phonon scattering. The CaAs3 monolayer also exhibits a high power factor due to the large Seebeck coefficient and electrical conductivity. Therefore, large ZT values of 1.72/1.58 were achieved for the n-type/p-type CaAs3 monolayer at 800 K. Compared with conventional 2D TE materials, the CaAs3 monolayer does not contain expensive heavy elements, which is beneficial for its practical applications as a TE material. Our results qualify the CaAs3 monolayer as a promising candidate for building excellent 2D TE devices.