Jing Zhang

A sandwiched Ta₂NiSe₅/MoTe₂/Graphene heterostructure device is demonstrated. In this device, efficient and polarization-sensitive photocarriers are generated in the top Ta₂NiSe₅ layer, rapidly separated through the middle MoTe₂ layer, and effectively collected by the bottom graphene layer. This device exhibits ultrabroadband and polarization-sensitive photodetection capabilities from visible light (520 nm) to short-wave infrared (2200 nm).

Abstract

Ultrabroadband and polarization-sensitive imaging are essential for pioneering advancements in intelligent technology, offering a pivotal pathway to multidimensional information extraction. However, the dearth of appropriate photosensitive semiconductors in the infrared region and the lack of suitably efficient device architecture for the separation and collection of photocarriers significantly impede the development of ultra-broadband and polarization-sensitive photodetectors. To address these challenges, a sandwiched Ta₂NiSe₅/MoTe₂/Graphene heterostructure device is engineered. In this device, efficient and polarization-sensitive photocarriers are generated in the top Ta₂NiSe₅ layer, rapidly separated through the middle MoTe₂ layer, and effectively collected by the bottom graphene layer. As a result, the developed photodetector exhibits an ultra-broadband and polarization-sensitive photoresponse that extends from visible light (520 nm) to short-wave infrared (2200 nm). At 2200 nm, the device displays a notable responsivity of 5.79 A W⁻¹, a specific detectivity of 10¹⁰ Jones, and an anisotropic ratio of 1.44. Furthermore, this device successfully demonstrates high-resolution ultra-broadband and polarized light imaging capabilities. This study thus presents an intriguing blueprint for the development of advanced 2D imaging platforms for future-generation intelligent systems.

A high-performance, self-powered, and broadband photodetector based on MoTe₂/InSe van der Waals heterostructure (vdWH) is presented. In self-powered mode, the device achieves a high responsivity and specific detectivity reaching 433.88 mA W⁻¹ and 1.65 × 10¹² Jones, respectively. It exhibits an ultra-fast response speed of 99/117 µs and 405–980 nm broadband photoresponse.

Abstract

Self-powered and broadband photodetectors have important applications in modern technologies and have garnered significant research interest with the increasing concern for green and energy-saving. The emerging 2D materials InSe is considered to be a promising candidate for next-generation photodetectors due to the high carrier mobility, excellent photoelectric response, and flexibility. However, due to its weak absorption of infrared light, it remains a challenging task to achieve high-performance, self-powered, and broadband photodetection. Here, a MoTe₂/InSe van der Waals heterostructure (vdWH) device is successfully constructed. Benefiting from the unique band alignment of the heterostructure, a strong built-in electric field is formed. Excitingly, the device exhibits excellent photovoltaic performance with a large open voltage and short circuit current of 390.19 mV and 20.32 nA, respectively. In particular, in self-powered mode, the responsivity (R) is up to 433.88 mA W⁻¹ and the specific detectivity (D*) reaches 1.65 × 10¹² Jones under 405 nm irradiation. Meanwhile, an ultrahigh I _light/I _dark ratio over 10⁴, a fast response speed of 99/117 µs, and a broadband photoresponse range from 405 to 980 nm are achieved. The device demonstrates excellent comprehensive self-powered photodetection performance. This work reveals the great potential of the MoTe₂/InSe vdWH for high-performance, broadband, and self-powered photodetection.

By utilizing the N 2p-O 2p orbital hybridization, the valence band electron energy band structure is effectively modulated, suppressing the electrical activity of oxygen vacancies and sustaining the photoconductive effect.

Abstract

Gallium oxide (β-Ga₂O₃) is a prominent representative of the new generation of wide-bandgap semiconductors, boasting a bandgap of ≈4.9 eV. However, the growth process of β-Ga₂O₃ materials introduces unavoidable oxygen vacancies (Vo), leading to persistent photoconductivity (PPC), a phenomenon that severely hinders device performance. In this study, an innovative approach is successfully developed by introducing high p-orbital energy nitrogen (N). This leads to the formation of a hybridized state with O 2p orbitals in β-Ga₂O₃, resulting in the creation of GaON and suppressing the electrical activity of Vo. Through meticulous experimentation and advanced computational methods, a comprehensive and insightful explanation of the regulation and mechanism underlying this passivation process is offered. Moreover, pn-junction solar-blind photodetectors are engineered using hybridized GaON thin films with p-type CuPc. These photodetectors demonstrate exceptional characteristics, including ultra-low dark current (10⁻¹⁴ A), high photo-to-dark current ratio (10⁶), and rapid decay speed (0.008 s) even at zero bias. Based on these advancements, a solar-blind ultraviolet communication system is designed, featuring straightforward and reliable encoding, easy implementation, and robust anti-interference capabilities.

This review examines the advancements in flexible perovskite solar cells (f-PSCs) over the last decade, focusing on significant improvements in power conversion efficiency, mechanical stability, and environmental resilience. It delves into material modifications, device optimization, large-area fabrication, and commercial application potential, providing insights into the future of renewable energy through f-PSCs.

Abstract

This review outlines the rapid evolution of flexible perovskite solar cells (f-PSCs) to address the urgent need for alternative energy sources, highlighting their impressive power conversion efficiency, which increases from 2.62% to over 24% within a decade. The unique optoelectronic properties of perovskite materials and their inherent mechanical flexibilities instrumental in the development of f-PSCs are examined. Various strategies proposed for material modification and device optimization significantly enhance efficiency and bending durability. The transition from small-scale devices to large-area photovoltaic modules for diverse applications is discussed in addition to the challenges and innovative solutions related to film uniformity and environmental stability. This review provides succinct yet comprehensive insights into the development of f-PSCs, paving the way for their integration into various applications and highlighting their potential in the renewable energy landscape.

Leveraging MXene as a potent signal booster, an electrochemical biosensing technique is developed for ultrasensitive detection of 5hmC-DNA. The technique not only achieves the lowest detection limit of 59 fM but also enables the direct detection of 5hmC-DNA targets from complex backgrounds including cellular genomic extracts and serum of irradiated or non-irradiated mice, suggesting its promising potential for diverse applications.

Abstract

5-Hydroxymethylcytosine in genomic DNA (5hmC-DNA), a predominant epigenetic mark, plays key roles in a broad range of bioprocesses such as cancer progression. However, efficient detection of 5hmC-DNA, especially from highly complex biological specimens, remains a harsh challenge due to its low abundance as well as the serious disturbance of non-targets. Leveraging MXene as the signal booster, an electrochemical biosensing technique is presented here for ultrasensitive detection of 5hmC-DNA from complex biological samples. The developed technique integrates enzyme-catalyzed transform of the hydroxyl group of 5hmC, sequence-specific recognition of the 5hmC-DNA targets, and facile electrochemical reaction. Remarkably, nanosized Ti₃C₂T _x MXene is introduced as a highly conductive agent, managing to greatly boost the signals. Exhibiting outstanding consistency and robustness, the technique not only achieves excellent linear responses in a broad range of 5hmC-DNA (1.0 × 10⁻¹³–1.0 × 10⁻⁹ m) with the lowest detection limit of 59 fM but also possesses excellent selectivity against 5hmC analogs of including cytosine (C)- and 5-methylcytosine (5mC). More importantly, a proof-of-concept validation demonstrates the extraordinary ability of this technique for directly detecting 5hmC-DNA from complex backgrounds including cellular genomic extracts and serum of irradiated or non-irradiated mice, suggesting its highly promising potential for diverse applications such as early cancer screening.

This work demonstrates a multisensory synapse with a graphene/α-In₂Se₃/graphene crossbar structure. The ferroelectric α-In₂Se₃ modulates the Schottky barrier height, regulating the conductance (G) and photoresponsivity (R). This enables simulating various electronic and optoelectronic synaptic characteristics, featuring linearly tunable electrical and optical weights. Such features facilitate in-sensor front-end processing and advanced processing, achieving a recognition accuracy rate of 97%.

Abstract

Integrated multifunctionality in visual information processing is crucial in the artificial intelligence era. Compared to the parallel human vision system, current bionic vision devices exhibit a complex structure with single functionality, challenging intelligent processing and integration. Here, a multisensory artificial synapse with a crossbar structure comprising graphene/α-In₂Se₃/graphene layers is demonstrated, merging sensing, memory, and computing while mimicking various synaptic properties. The Schottky barrier height is modulated by the polarization of ferroelectric semiconductor α-In₂Se₃, enabling reconfigurable device conductance and photoresponsivity. This conductance emulates synaptic short-term and long-term plasticity through electrical pulse modulation, boasting a rapid 40 ns programming speed. The device also exhibits linearly regulated photoresponsivity under illumination, with synaptic plasticity from optical pulses. The fusion of electronic and optoelectronic devices enables both image front-end processing and advanced post-processing. In-sensor front-end processing enhances subsequent processing efficiency, with pattern recognition accuracy reaching 97%. This design fosters the advancement of multisensory and highly integrated neuromorphic vision systems.

Nature Nanotechnology, Published online: 15 January 2024; doi:10.1038/s41565-024-01604-6

Author Correction: Spontaneous broken-symmetry insulator and metals in tetralayer rhombohedral graphene

Nature Communications, Published online: 13 January 2024; doi:10.1038/s41467-024-44792-4

The intrinsic photovoltaic effect (IPVE) in noncentrosymmetric materials has the potential to overcome the limitations of traditional photovoltaic devices. Here, the authors report the observation of a strong and gate-tunable IPVE in 1D grain boundaries of a van der Waals semiconductor, ReS2.

This study demonstrates a bifunctional Ag/MgFe₂O₄@SCW reactor with sandwich structure, which can be used for efficient SSG and Cr(VI) reduction. An ultra-high evaporation rate of 1.55 kg m⁻² h⁻¹ is achieved under 1 sun. High antibacterial activity, desalination capability, and water-harvesting capacity are exhibited. More importantly, the Ag/MgFe₂O₄@SCW photocatalyst can remove up to 96.1% of Cr(VI) after 180-min illumination.

Abstract

The severe deterioration of the marine ecosystem significantly negatively impacts the performance of solar-driven steam generation (SSG) and the quality of the obtained freshwater. Herein, a bifunctional Ag/MgFe₂O₄@SCW reactor with a sandwich structure is designed for efficient SSG and Cr(VI) reduction, which is constructed via in situ deposit Ag nanoparticles (NPs) and MgFe₂O₄ onto surface carbonized wood (SCW). Owing to the advanced sandwich structure and strong interfacial interactions between each component, an ultra-high evaporation rate of 1.55 kg m⁻² h⁻¹ and the efficiency of 88.6% are achieved using Ag/MgFe₂O₄@SCW under 1 sun. The system exhibits the long-term evaporation performance in the simulated sewage and strong acid/base solutions along with water-harvesting capacity in outdoor solar desalination. The quality of distilled water after desalination of actual seawater and NaCl solutions with different concentrations meets the WHO-recommended drinkable water standards. Furthermore, Ag/MgFe₂O₄@SCW shows outstanding antibacterial property, self-desalting capacity, as well as reusability and structure stability. Most importantly, the fast carrier separation endows Ag/MgFe₂O₄@SCW with superior photocatalytic activity and Cr(VI) photoreduction of up to 96.1% after 180 min of illumination. The bifunctional Ag/MgFe₂O₄@SCW reactor provides an advanced synergistic mechanism for improving SSG and photocatalytic performance, while being promising for solar-powered production of clean water.

Eu³⁺-directed supramolecular metallogels are constructed by orthogonal self-assembly of hydrogen bonding in ligand and Eu³⁺ based coordination interactions in MeOH solution, possessing shape-persistent 3D network structure. The cross-linked supramolecular metallogels show pH, K⁺, F⁻, and metallo-induced reversible gel-sol transition and tunable luminescence properties. These findings are useful in the studies of molecular switches, dynamic assemblies, and smart luminescent materials.

Abstract

Smart luminescent materials that have the ability to reversibly adapt to external environmental stimuli and possess a wide range of responses are continually emerging, which place higher demands on the means of regulation and response sites. Here, europium ions (Eu³⁺)-directed supramolecular metallogels are constructed by orthogonal self-assembly of Eu³⁺ based coordination interactions and hydrogen bonding. A new organic ligand (L) is synthesized, consisting of crown ethers and two flexible amide bonds-linked 1,10-phenanthroline moieties to coordinate with Eu³⁺. Synergistic intermolecular hydrogen bonding in L and Eu³⁺-L coordination bonding enable Eu³⁺ and L to self-assemble into shape-persistent 3D coordination metallogels in MeOH solution. The key to success is the utilization of crown ethers, playing dual roles of acting both as building blocks to build L with C ₂-symmetrical structure, and as the ideal monomer for increasing the energy transfer from L to Eu³⁺’s excited state, thus maintaining the excellent luminescence of metallogels. Interestingly, such assemblies show K⁺, pH, F⁻, and mechano-induced reversible gel-sol transitions and tunable luminescence properties. Above findings are useful in the studies of molecular switches, dynamic assemblies, and smart luminescent materials.

Ambipolar electrolyte-gated transistors based on reduced graphene oxide (rGO-EGTs) are ultra-sensitive and highly specific immunosensors. The physics and chemistry ruling the device operation are still not fully unraveled. This work aims to elucidate the nature of the observed sensitivity, by proposing a physical–chemical model that quantitatively correlates the biorecognition events at the gate electrode and the electronic properties of rGO-EGTs.

Abstract

Ambipolar electrolyte-gated transistors (EGTs) based on reduced graphene oxide (rGO) have been demonstrated as ultra-sensitive and highly specific immunosensors. However, the physics and chemistry ruling the device operation are still not fully unraveled. In this work, the aim is to elucidate the nature of the observed sensitivity of the device. Toward this aim, a physical–chemical model that, coupled with the experimental characterization of the rGO-EGT, allows one to quantitatively correlate the biorecognition events at the gate electrode and the electronic properties of rGO-EGT is proposed. The equilibrium of biorecognition occurring at the gate electrode is shown to determine the apparent charge neutrality point (CNP) of the rGO channel. The multiparametric analysis of the experimental transfer characteristics of rGO-EGT reveals that the recognition events modulate the CNP voltage, the excess carrier density Δn, and the quantum capacitance of rGO. This analysis also explains why hole and electron carrier mobilities, interfacial capacitance, the curvature of the transfer curve, and the transconductances are insensitive to the target concentration. The understanding of the mechanisms underlying the transistor transduction of the biorecognition events is key for the interpretation of the response of the rGO-EGT immunosensors and to guide the design of novel and more sensitive devices.

Field-Free Switching

In article number 2308219, Hyunsoo Yang, Weisheng Zhao, Shuyuan Shi, and co-workers address a critical technological challenge within the field of SOT-MTJ technology by designing SOT layers with compositional gradients to achieve field-free deterministic perpendicular magnetization switching. Importantly, this technique is readily applicable to high-density CMOS-compatible integrated processes, thereby further enhancing the potential applications of field-free SOT-MTJ in the context of computing-in-memory technologies.

Artificial Neural Networks

In article number 2307971, Gunuk Wang and Young Ran Park implement a mixed-dimensional halide perovskite synaptic array with controlled doping concentration to enable selector-free analog switching and increase learning efficiency. The mixed-dimensional device system with controlled QD size represents a novel bottom-up strategy for facilitating desirable neuromorphic functions with improved learning capacity and energy efficiency, while mitigating undesired neural signals.

2D metal-organic frameworks (MOFs), by virtue of their large aspect ratio, unique composition, and structural characteristics, show great promise in catalytic energy conversion applications. A comprehensive overview of the state-of-the-art reports 2D MOFs on the synthetic techniques, identification of catalytic active sites, and electro/photocatalytic applications are provided, along with the perspectives for the future development of 2D MOF electro/photocatalysts.

Abstract

The demand for the exploration of highly active and durable electro/photocatalysts for renewable energy conversion has experienced a significant surge in recent years. Metal-organic frameworks (MOFs), by virtue of their high porosity, large surface area, and modifiable metal centers and ligands, have gained tremendous attention and demonstrated promising prospects in electro/photocatalytic energy conversion. However, the small pore sizes and limited active sites of 3D bulk MOFs hinder their wide applications. Developing 2D MOFs with tailored thickness and large aspect ratio has emerged as an effective approach to meet these challenges, offering a high density of exposed active sites, better mechanical stability, better assembly flexibility, and shorter charge and photoexcited state transfer distances compared to 3D bulk MOFs. In this review, synthesis methods for the most up-to-date 2D MOFs are first overviewed, highlighting their respective advantages and disadvantages. Subsequently, a systematic analysis is conducted on the identification and electronic structure modulation of catalytic active sites in 2D MOFs and their applications in renewable energy conversion, including electrocatalysis and photocatalysis (electro/photocatalysis). Lastly, the current challenges and future development of 2D MOFs toward highly efficient and practical electro/photocatalysis are proposed.

Nature Materials, Published online: 12 January 2024; doi:10.1038/s41563-023-01779-8

The authors study spin transport anisotropy in a 5.5 nm black phosphorus ribbon encapsulated by boron nitride.

Flexible perovskite solar cells (F-PSCs) are gaining importance for diverse applications, yet face concern about mechanical robustness. This review explores recent advancements in enhancing the mechanical stability of F-PSCs, including soft perovskite optimization, crystal grain regulation, flexible electrodes, substrate selection, and other factors. Challenges and perspectives for F-PSCs are also discussed.

Abstract

The remarkable progress in perovskite solar cell (PSC) technology has witnessed a remarkable leap in efficiency within the past decade. As this technology continues to mature, flexible PSCs (F-PSCs) are emerging as pivotal components for a wide array of applications, spanning from powering portable electronics and wearable devices to integrating seamlessly into electronic textiles and large-scale industrial roofing. F-PSCs characterized by their lightweight, mechanical flexibility, and adaptability for cost-effective roll-to-roll manufacturing, hold immense commercial potential. However, the persistent concerns regarding the overall stability and mechanical robustness of these devices loom large. This comprehensive review delves into recent strides made in enhancing the mechanical stability of F-PSCs. It covers a spectrum of crucial aspects, encompassing perovskite material optimization, precise crystal grain regulation, film quality enhancement, strategic interface engineering, innovational developed flexible transparent electrodes, judicious substrate selection, and the integration of various functional layers. By collating and analyzing these dedicated research endeavors, this review illuminates the current landscape of progress in addressing the challenges surrounding mechanical stability. Furthermore, it provides valuable insights into the persistent obstacles and bottlenecks that demand attention and innovative solutions in the field of F-PSCs.

A highly stretchable (534.5%), conductive (4.54 S m⁻¹), thermogalvanic (1.82 mV K⁻¹) hydrogel is fabricated, which remains conductive (3.86 S m⁻¹) at −20 °C and hardly shows degradation in thermoelectrical performance over 10 days. Besides, acting as a self-powered e-skin, the hydrogel is combined with deep learning technology for signature recognition and biometric authentication, achieving an accuracy of 92.97%.

Abstract

Self-powered electronic skins (e-skins), as on-skin human-machine interfaces, play a significant role in cyber security and personal electronics. However, current self-powered e-skins are primarily constrained by complex fabricating process, intrinsic stiffness, signal distortion under deformation, and inadequate comprehensive performance, thereby hindering their practical applications. Herein, a novel highly stretchable (534.5%), ionic conductive (4.54 S m⁻¹), thermogalvanic (1.82 mV K⁻¹) hydrogel (TGH) is facilely fabricated by a one-pot method. Owing to the formation of Li⁺(H₂O)_n hydration structure, the TGH presents excellent anti-freezing and non-drying performance. It remains flexible and conductive (3.86 S m⁻¹) at −20 °C and shows no obvious degradation in the thermoelectrical performance over 10 days. Besides, acting as a self-powered e-skin, the TGH combined with deep learning technology for signature recognition and biometric authentication is successfully demonstrated, achieving an accuracy of 92.97%. This work exhibits the TGH-based e-skin's tremendous potential in the new generation of human-computer interaction and information security.

The thermally-induced dehydration process of the [Eu(BTC)(H₂O)₆] coordination polymer results in a modification of the spectroscopic properties of the Eu³⁺ ion. This modification facilitates the development of a ratiometric and lifetime-based thermal history phosphor, exhibiting the highest relative sensitivity reported to date.

Abstract

The capacity to discern the highest temperature that an object is subjected to is a crucial diagnostic tool. Consequently, the pursuit of materials that enable the luminescence-based investigation of the thermal history of an object with high sensitivity is of great importance from the functional applications standpoint. This study aims to present a multiparametric thermal history phosphor based on the luminescent coordination polymer [Eu(BTC)(H₂O)₆] [Eu(BTC)-1, where H₃BTC = 1,3,5-benzenetricarboxylic acid]. The progressive dehydration that Eu(BTC)-1 undergoes as a function of temperature increase in the 343–425 K range results in significant alterations in both the shape of the Eu³⁺ ions emission spectrum and the depopulation kinetics of their ⁵D₀ level. Based on this occurrence, a thermal history phosphor with an unprecedentedly high relative sensitivity of 11.3% K⁻¹ in ratiometric mode, and 1.8% K⁻¹ in lifetime-based mode, is developed. The outcomes of this research are expected to stimulate a wide interest in the exploitation of (porous) coordination polymer-type materials for the development of thermal history phosphors.

Through DNA-programmed (de)hybridization, a hierarchical nanoprobe UCNP-QDs-GNPs, bridged by heterobivalent DNA-conjugated QDs, can transfer near-infrared excitation to amplified fluorescence signal and enhanced photodynamic activity upon recognition of microRNA target. It enables sensitive imaging of low-abundance microRNA biomarkers and image-guided ablation of deep tumors, offering promises for early cancer diagnosis and treatment.

Abstract

Accurate and sensitive analysis of cancer-associated microRNAs in living tissue is of great significance for the early diagnosis and treatment of cancer. Herein, a hierarchical nanoprobe denoted as UCNP-QDs-GNPs is delicately designed, where a near-infrared (NIR) absorptive upconversion nanoparticle (UCNP) serves as the core, broad-absorptive and bright emissive quantum dots (QDs) and emission-quencher gold nanoparticles (GNPs) surround as satellites for microRNA imaging and image-guided cancer therapy. Through the programmed assembly of heterobivalent DNA-conjugated QDs with DNA-modified GNPs and UCNPs, the well-defined nanostructured UCNP-QDs-GNPs are generated with quenched fluorescence. Upon encountering the microRNA-21 target, GNPs underwent catalytic disassembly, resulting in the concurrent recovery and amplification of fluorescence from QDs and UCNPs, which enabled sensitive imaging and quantification of microRNA-21 within living cells. Furthermore, dithiol-constituted aggregation-induced emission (AIE) photosensitizers bonded on the surface of QDs, are effectively photosensitized by the QDs. The NIR excitation harvested by UCNPs is therefore efficiently transferred to QDs and subsequently converged on the AIE photosensitizers, boosting photodynamic activity for image-guided therapy in deep-seated tumors. The DNA-programmed (de)hybridization strategy, facilitating the conversion of NIR excitation into imaging signals and photodynamic activity, offers a promising avenue for the early theranostics of malignancies.

Nature Materials, Published online: 11 January 2024; doi:10.1038/s41563-023-01780-1

Direct observation of noble gas structures has been achieved at room temperature using electron microscopy. This was enabled by trapping them between two layers of graphene, where they form two-dimensional clusters.

Nature Physics, Published online: 11 January 2024; doi:10.1038/s41567-023-02317-8

In its superconducting state, MoTe2 displays oscillations arising from an edge supercurrent, and when it is near niobium, there is an incompatibility between electron pairs diffusing from niobium and the pairs intrinsic to MoTe2. Insight into this competition between pairs is obtained by monitoring the noise spectrum of the MoTe2 supercurrent oscillations.

Nature, Published online: 10 January 2024; doi:10.1038/d41586-023-03992-6

Ultrathin materials have long been touted as a solution to the problems faced by the ever-growing semiconductor industry. Evidence that 3D chips can be built from 2D semiconductors suggests that the hype was justified.

Nature, Published online: 10 January 2024; doi:10.1038/s41586-023-06860-5

Monolithic three-dimensional integration of two-dimensional field-effect transistors enables improved integration density and multifunctionality to realize ‘More Moore’ and ‘More than Moore’ technologies.

Nature Nanotechnology, Published online: 11 January 2024; doi:10.1038/s41565-023-01576-z

High-density transparent microelectrode arrays with platinum-nanoparticle deposited and interlayer-doped double-layer graphene enable multimodal optical and electrical recordings with high spatiotemporal resolution to decode neural dynamics at different cortical layers from surface potentials.

Nature Nanotechnology, Published online: 11 January 2024; doi:10.1038/s41565-023-01570-5

Bidirectional neural interface electronic devices offer therapeutic options. Here, the authors present wafer-scale fabrication of flexible nanoporous graphene-based implantable microelectrode arrays with low impedance and high charge injection for in vivo brain recording and nerve stimulation.

This work employs an in-situ growth method to load layered double hydroxides (LDH) onto transition metal carbides (MXene), synthesizing a novel electronic packaging material (MXene@LDH). The opimized MXene@LDH shows a remarkable minimum reflection loss (RL) of −52.064 dB and a maximum effective absorption bandwidth (EAB) of 4.5 GHz with high thermal conductivity and flame retardancy.

Abstract

Due to the increased integration and miniaturization of electronic devices, traditional electronic packaging materials, such as epoxy resin (EP), cannot solve electromagnetic interference (EMI) in electronic devices. Thus, the development of multifunctional electronic packaging materials with superior electromagnetic wave absorption (EMA), high heat dissipation, and flame retardancy is critical for current demand. This study employs an in-situ growth method to load layered double hydroxides (LDH) onto transition metal carbides (MXene), synthesizing a novel composite material (MXene@LDH). MXene@LDH possesses a sandwich structure and exhibits excellent EMA performance, thermal conductivity, and flame retardancy. By adjusting the load of LDH, under the synergistic effect of multiple factors, such as dielectric and polarization losses, this work achieves an EMA material with a remarkable minimum reflection loss (RL) of −52.064 dB and a maximum effective absorption bandwidth (EAB) of 4.5 GHz. Furthermore, MXene@LDH emerges a bridging effect in EP, namely MXene@LDH/EP, leading to a 118.75% increase in thermal conductivity compared to EP. Simultaneously, MXene@LDH/EP contributes to the enhanced flame retardancy compared to EP, resulting in a 46.5% reduction in the total heat release (THR). In summary, this work provides a promising candidate advanced electronic packaging material for high-power density electronic packaging.