Nanoscience News (<front>)

Polymeric charge transporters hold immense potential for inverted perovskite solar cells due to their tunable structures, high conductivity, and inherent flexibility. This review comprehensively explores recent advancements in these polymeric materials, while also delving into the remaining challenges and proposing practical design strategies for their future optimization.

Abstract

Inverted perovskite solar cells (PSCs) hold exceptional promise as next-generation photovoltaic technology, where both perovskite absorbers and charge-transporting materials (CTMs) play critical roles in cell performance. In recent years, polymeric CTMs have played an important role in developing efficient, stable, and large-area inverted PSCs due to their unique properties of high conductivity, tunable structures, and mechanical flexibility. This review provides a comprehensive overview of polymeric CTMs used in inverted PSCs, encompassing polymeric hole transport materials (HTMs) and electron transport materials (ETMs). the relationship between their molecular structures, modification strategies are systematically summarized and analyzed for adjusting energy levels, and improving charge extraction, enabling a deep understanding of these widely used materials. The review also explores effective strategies for designing even more efficient polymeric CTMs. Finally, an outlook is proposed on the exciting research of novel polymeric CTMs, paving the way for their commercialized applications in PSCs.

CART cell therapy has proven effective for blood cancers but struggles with solid tumors due to diverse antigens and complex environments. Recent efforts focus on improving CAR design and validation platforms. Advances in protein engineering, machine learning, and organoid systems aim to enhance CAR-T therapy against solid tumors. Some solid tumors, like neuroblastoma, have responded well in trials.

Abstract

Cancer immunotherapy, specifically Chimeric Antigen Receptor (CAR)-T cell therapy, represents a significant breakthrough in treating cancers. Despite its success in hematological cancers, CAR-T exhibits limited efficacy in solid tumors, which account for more than 90% of all cancers. Solid tumors commonly present unique challenges, including antigen heterogeneity and complex tumor microenvironment (TME). To address these, efforts are being made through improvements in CAR design and the development of advanced validation platforms. While efficacy is limited, some solid tumor types, such as neuroblastoma and gastrointestinal cancers, have shown responsiveness to CAR-T therapy in recent clinical trials. In this review, it is first examined both experimental and computational strategies, such as protein engineering coupled with machine learning, developed to enhance T cell specificity. The challenges and methods associated with T cell delivery and in vivo reprogramming in solid tumors is discussed. It is also explored the advancements in engineered organoid systems, which are emerging as high-fidelity in vitro models that closely mimic the complex human TME and serve as a validation platform for CAR discovery. Collectively, these innovative engineering strategies offer the potential to revolutionize the next generation of CAR-T therapy, ultimately paving the way for more effective treatments in solid tumors.

This review addresses challenges and recent advances in fast-charging solid-state batteries, focusing on solid electrolyte and electrode materials, as well as interfacial chemistries. The role of multiscale modeling and simulation in understanding Li+ transport and interfacial phenomena is emphasized, providing insights into materials, strategies, and future prospects for high-performance, fast-charging solid-state batteries.

Abstract

The ability to rapidly charge batteries is crucial for widespread electrification across a number of key sectors, including transportation, grid storage, and portable electronics. Nevertheless, conventional Li-ion batteries with organic liquid electrolytes face significant technical challenges in achieving rapid charging rates without sacrificing electrochemical efficiency and safety. Solid-state batteries (SSBs) offer intrinsic stability and safety over their liquid counterparts, which can potentially bring exciting opportunities for fast charging applications. Yet realizing fast-charging SSBs remains challenging due to several fundamental obstacles, including slow Li+ transport within solid electrolytes, sluggish kinetics with the electrodes, poor electrode/electrolyte interfacial contact, as well as the growth of Li dendrites. This article examines fast-charging SSB challenges through a comprehensive review of materials and strategies for solid electrolytes (ceramics, polymers, and composites), electrodes, and their composites. In particular, methods to enhance ion transport through crystal structure engineering, compositional control, and microstructure optimization are analyzed. The review also addresses interface/interphase chemistry and Li+ transport mechanisms, providing insights to guide material design and interface optimization for next-generation fast-charging SSBs.

This review summarizes recent advanced catalysts applied in thermal catalysis, microwave-assisted catalysis, photocatalysis, electrocatalysis, and enzymatic catalysis reaction systems for the chemical recycling of plastic waste into valuable feedstocks.

Abstract

Plastic products bring convenience to various aspects of the daily lives due to their lightweight, durability and versatility, but the massive accumulation of post-consumer plastic waste is posing significant environmental challenges. Catalytic methods can effectively convert plastic waste into value-added feedstocks, with catalysts playing an important role in regulating the yield and selectivity of products. This review explores the latest advancements in advanced catalysts applied in thermal catalysis, microwave-assisted catalysis, photocatalysis, electrocatalysis, and enzymatic catalysis reaction systems for the chemical recycling of plastic waste into valuable feedstocks. Specifically, the pathways and mechanisms involved in the plastics recycling process are analyzed and presented, and the strengths and weaknesses of various catalysts employed across different reaction systems are described. In addition, the structure-function relationship of these catalysts is discussed. Herein, it is provided insights into the design of novel catalysts applied for the chemical recycling of plastic waste and outline challenges and future opportunities in terms of developing advanced catalysts to tackle the “white pollution” crisis.

In this review, the recent development of deep-blue (≤465 nm) perovskite light-emitting diodes (PeLEDs) are summarized, using different perovskite nanomaterials, including nanocrystals (NCs), quantum dots (QDs), nanoplatelets (NPLs), quasi-2D thin film, 3D bulk thin film, as well as lead-free perovskite nanomaterials. The challenges, optimization, and the future of deep-blue PeLEDs are discussed.

Abstract

In this review, the recent development of blue perovskite light-emitting diodes (PeLED) are summarized. On deep-blue (≤465 nm) perovskite nanomaterials of different structural forms are mainly focused, including nanocrystals (NCs), quantum dots (QDs), nanoplatelets (NPLs), quasi-2D thin film, 3D bulk thin film, as well as lead-free perovskite nanomaterials. The current challenges are also examined in producing efficient deep-blue PeLED, such as material and spectral instability, imbalance charge transport, Joule heat impact, and poor optoelectronic performance. Several strategies are further discussed to overcome these challenges and achieve efficient deep-blue PeLED for next-generation display technology.

Incorporating tris(trimethylsilyl)-based additives, this work addresses the elimination reaction of methyl trifluoroethyl carbonate (FEMC) to contrast a homogeneous robust polymer-rich cathode-electrolyte interphase. Using the optimized electrolyte, the LiCoO2 cathode can maintain 95% after 500 cycles with a high cut-off voltage of 4.6 V. This study establishes a foundational framework for employing linear fluorocarbonates in high voltage systems and provides innovative insights into CEI design and construction.

Abstract

Stabilizing LiCoO2 (LCO) cathode at high voltages is still challenging in lithium-ion batteries (LIBs). Although fluorinated solvents are utilized in high-voltage systems for their superior oxidation resistance, linear fluorinated carbonates still undergo elimination reactions at high voltages, producing corrosive substances that compromise electrode materials. This study addresses the elimination reaction of methyl trifluoroethyl carbonate (FEMC) by incorporating tris(trimethylsilyl)-based additives, thereby constructing a homogeneous and robust polymer-rich cathode-electrolyte interphase (CEI). With the incorporation of tris(trimethylsilyl)phosphite in the optimized electrolyte, the capacity of the coin cell with LCO as the cathode can maintain 95% after 500 cycles with a high cut-off voltage of 4.6 V. This study establishes a foundational framework for employing linear fluorocarbonates in high-voltage systems and provides innovative insights into CEI design and construction.

Pristine van der Waals homojunctions consisting of 2H-MoTe2 layers with asymmetric thickness are constructed to eliminate heterogenous interfaces and obtain clean boundaries. The layer-engineered energy bands of 2H-MoTe2 layers induce a built-in electric field at the interface, enabling self-powered photodetection. Furthermore, a 10 × 10 array based on 2H-MoTe2 homojunction devices realize zero-power consumption imaging functions.

Abstract

Van der Waals junctions hold significant potentials for various applications in multifunctional and low-power electronics and optoelectronics. The multistep device fabrication process usually introduces lattice mismatch and defects at the junction interfaces, which deteriorate device performance. Here the layer engineering synthesis of van der Waals homojunctions consisting of 2H-MoTe2 with asymmetric thickness to eliminate heterogenous interfaces and thus obtain clean interfaces is reported. Experimental results confirm that the homostructure nature gives rise to the formation of pristine van der Waals junctions, avoiding chemical disorders and defects. The ability to tune the energy bands of 2H-MoTe2 continuously through layer engineering enables the creation of adjustable built-in electric field at the homojunction boundaries, which leads to the achievement of self-powered photodetection based on the obtained 2H-MoTe2 films. Furthermore, the successful integration of 2H-MoTe2 homojunctions into an image sensor with 10 × 10 pixels, brings about zero-power consumption and near-infrared imaging functions. The pristine van der Waals homojunctions and effective integration strategies shed new insights into the development of large-scale application for two-dimensional materials in advanced electronics and optoelectronics.

A self-lithiated tin (Sn)-carbon (C) composite interlayer (LSCI) capable of enhancing electrochemical/structural stability and homogenizing lithium (Li)-ion transport across the Li/solid-state electrolyte (SSE) interfaces enables an all-solid-state lithium–sulfur battery (ASSLSBs) with high cycling stability and rate capability.

Abstract

All-solid-state lithium–sulfur batteries (ASSLSBs) have attracted intense interest due to their high theoretical energy density and intrinsic safety. However, constructing durable lithium (Li) metal anodes with high cycling efficiency in ASSLSBs remains challenging due to poor interface stability. Here, a compositionally stable, self-lithiated tin (Sn)-carbon (C) composite interlayer (LSCI) between Li anode and solid-state electrolyte (SSE), capable of homogenizing Li-ion transport across the interlayer, mitigating decomposition of SSE, and enhancing electrochemical/structural stability of interface, is developed for ASSLSBs. The LSCI-mediated Li metal anode enables stable Li plating/stripping over 7000 h without Li dendrite penetration. The ASSLSBs equipped with LSCI thus exhibit excellent cycling stability of over 300 cycles (capacity retention of ≈80%) under low applied pressure (<8 MPa) and demonstrate improved rate capability even at 3C. The enhanced electrochemical performance and corresponding insights of the designed LSCI broaden the spectrum of advanced interlayers for interface manipulation, advancing the practical application of ASSLSBs.

A novel heterogeneous Na4Fe3(PO4)2(P2O7)/Na2VTi(PO4)3 material achieves high purity and high crystallization by the mutual promotion of intergrowth structures. Benefiting from the interfacial charge redistribution effect between the heterogeneous phases, the electronic conductivity and ion diffusion are greatly improved. The optimized Na4Fe3(PO4)2(P2O7)/Na2VTi(PO4)3 cathode, with a reversible three-electron redox reaction, exhibits high specific capacity and long cycling life.

Abstract

Na superionic conductor (NASICON)-structured compounds demonstrate great application potential by their robust framework and compositional diversity. However, they are blamed for the mediocre energy density, and achieving both multielectron reaction and good cycling stability simultaneously is challenging. Herein, a novel heterogeneous Na4Fe3(PO4)2(P2O7)/Na2VTi(PO4)3 (NFPP/NVTP) material with stable multielectron reaction is constructed by spray drying technology. The mutual promotion effect of intergrowth structures effectively improves the purity and the crystallization of NFPP/NVTP during the fabrication process, which is beneficial to the high capacity and cycling stability. As a result, the optimized NFPP/NVTP demonstrates a high reversible capacity of 155.3 mAh g−1 at 20 mA g−1 and outstanding cycling stability with 82.9% capacity retention over 2500 cycles at 1 A g−1, which are much superior to those of NFPP and NVTP individually. Even in full cell configuration, the energy density remains high at ≈380 Wh kg−1 based on the cathode mass. The high capacity of NFPP/NVTP is also attributed to the successive reduction/oxidation mechanism involving the introduction of Ti3+ and interfacial charge redistribution effect between the heterogeneous phases, which greatly improve the electronic and ionic conductivity. Moreover, high reversible structural evolution during the multisodium storage process further guarantees excellent cycling stability.

The outstanding double-cable-based single-component material, DCPY2, exhibits a suppressed charge recombination process alongside efficient charge generation. This results in a high fill factor and short-circuit current, yielding an efficiency to 13.85%. The slow recombination process in DCPY2 compared to binary systems is attributed to the reduced wavefunction overlap between donor and acceptor from inherent alkyl linker and enhanced acceptor aggregation.

Abstract

Single-component organic solar cells based on double cable polymers have achieved remarkable performance, with DCPY2 reaching a high efficiency of over 13%. In this study, DCPY2 is further optimized with an efficiency of 13.85%, maintaining a high fill factor (FF) without compromising the short circuit current. Despite its intermixed morphology, DCPY2 shows a reduced recombination rate compared to their binary counterpart (PBDB-T:Y-O6). This slower recombination in DCPY2 is attributed to the reduced wavefunction overlap of delocalized charges, achieved by spatially separating the donor and acceptor units with an alkyl linker, thereby restricting the recombination pathways. Adding 1,8-diiodooctane (DIO) into DCPY2 further reduced the recombination rate by facilitating acceptor aggregation, allowing free charges to become more delocalized. The DIO-assisted aggregation in DCPY2 (5% DIO) is evidenced by an increased pseudo-pure domain size of Y-O6. Fine molecular control at the donor/acceptor interface in the double-cable polymer achieves reduced non-geminate recombination under efficient charge generation, increased mobility, and charge carrier lifetime, thereby achieving superior performance. Nevertheless, the FF is still limited by relatively low mobility compared to the blend, suggesting the potential for further mobility improvement through enhanced higher-dimensional packing of the double-cable material.

An injectable hydrogel comprising recombinant spider silk proteins is formed through ultrasound and thermally induced phase transition. Thanks to SpyTag/SpyCatcher chemistry, neurotrophins such as CNTF are covalently immobilized onto the hydrogels, enabling sustained protein delivery, prolonged neuroprotection, and enhanced axon regrowth following optic nerve injury. This system serves as a safe and versatile platform for the delivery of therapeutic proteins.

Abstract

The ability to deliver protein therapeutics in a minimally invasive, safe, and sustained manner, without resorting to viral delivery systems, will be crucial for treating a wide range of chronic injuries and diseases. Among these challenges, achieving axon regeneration and functional recovery post-injury or disease in the central nervous system remains elusive to most clinical interventions, constantly calling for innovative solutions. Here, a thermally responsive hydrogel system utilizing recombinant spider silk protein (spidroin) is developed. The protein solution undergoes rapid sol-gel transition at an elevated temperature (37 °C) following brief sonication. This thermally triggered gelation confers injectability to the system. Leveraging SpyTag/SpyCatcher chemistry, the hydrogel, composed of SpyTag-fusion spidroin, can be functionalized with diverse SpyCatcher-fusion bioactive motifs, such as neurotrophic factors (e.g., ciliary neurotrophic factor) and cell-binding ligands (e.g., laminin), rendering it well-suited for neuronal culturing. More importantly, the intravitreous injection of the protein materials decorated with SpyCatcher-fusion CNTF into the vitreous body after optic nerve injury leads to prolonged JAK/STAT3 signaling, increased neuronal survival, and enhanced axon regeneration. This study illustrates a generalizable material system for injectable and sustained delivery of protein therapeutics for neuroprotection and regeneration, with the potential for extension to other chronic diseases and injuries.

The raw data obtained directly from sensors in the noisy analogue domain is often unstructured, which lacks a predefined format or organization and does not conform to a specific data model. Optoelectronic devices for in-sensor visual processing can integrate perception, memory, and processing functions in the same physical units, which can compress and structure vision without extra optoelectronic conversion.

Abstract

The demand for accurate perception of the physical world leads to a dramatic increase in sensory nodes. However, the transmission of massive and unstructured sensory data from sensors to computing units poses great challenges in terms of power-efficiency, transmission bandwidth, data storage, time latency, and security. To efficiently process massive sensory data, it is crucial to achieve data compression and structuring at the sensory terminals. In-sensor computing integrates perception, memory, and processing functions within sensors, enabling sensory terminals to perform data compression and data structuring. Here, vision sensors are adopted as an example and discuss the functions of electronic, optical, and optoelectronic hardware for visual processing. Particularly, hardware implementations of optoelectronic devices for in-sensor visual processing that can compress and structure multidimensional vision information are examined. The underlying resistive switching mechanisms of volatile/nonvolatile optoelectronic devices and their processing operations are explored. Finally, a perspective on the future development of optoelectronic devices for in-sensor computing is provided.

Advanced aqueous batteries are promising alternatives for grid energy storage. Understanding and mastering the proton activities in aqueous electrolytes will guide the design of sustainable and long-lasting aqueous batteries. This Perspective comments on the current understanding of the thermodynamic and kinetic perspectives of proton activities and highlights future research directions for aqueous batteries.

Abstract

Advanced aqueous batteries are promising solutions for grid energy storage. Compared with their organic counterparts, water-based electrolytes enable fast transport kinetics, high safety, low cost, and enhanced environmental sustainability. However, the presence of protons in the electrolyte, generated by the spontaneous ionization of water, may compete with the main charge-storage mechanism, trigger unwanted side reactions, and accelerate the deterioration of the cell performance. Therefore, it is of pivotal importance to understand and master the proton activities in aqueous batteries. This Perspective comments on the following scientific questions: Why are proton activities relevant? What are proton activities? What do we know about proton activities in aqueous batteries? How do we better understand, control, and utilize proton activities?

The defect chemistry is focused on governing high-voltage cathode materials for next-generation high-energy-density lithium-ion batteries. The classifications, formation, and evolution mechanisms of defects are emphasized to explore the intricate relationship between defective structures and electrochemical behaviors. The cutting-edge cross-scale characterization techniques and defect engineering strategies that mitigate or utilize defects are highlighted.

Abstract

High-voltage cathodes (HVCs) have emerged as a paramount role for the next-generation high-energy-density lithium-ion batteries (LIBs). However, the pursuit of HVCs comes with inherent challenges related to defective structures, which significantly impact the electrochemical performance of LIBs. The current obstacle lies in the lack of a comprehensive understanding of defects and their precise effects. This perspective aims to provide insights into defect chemistry for governing HVCs. The classifications, formation mechanisms, and evolution of defects are outlined to explore the intricate relationship between defects and electrochemical behavior. The pressing need for cutting-edge characterization techniques that comprehensively investigate defects across various temporal and spatial scales is emphasized. Building on these fundamental understandings, engineering strategies such as composition tailoring, morphology design, interface modification, and structural control to mitigate or utilize defects are thoroughly discussed for enhanced HVCs performance. These insights are expected to provide vital guidelines for developing high-performance HVCs for next-generation high-energy lithium-ion batteries.

A multispectral-responsive metasurface simultaneously modulates directional laser reflection and dynamic infrared emissivity, enabling robust dual-band camouflage and dual-modal anti-counterfeiting. By synergistically integrating spatial and spectral control, this approach greatly expands capabilities for manipulating multiple physical parameters, providing a versatile approach for advanced information encryption, holography, and thermal management applications in complex scenarios.

Abstract

Responsive metasurfaces can efficiently control the propagation and spectral properties of electromagnetic (EM) waves, emerging as an attractive technology in energy and information fields. However, achieving non-interference manipulation of near-infrared (NIR) laser wavelength and mid-infrared (MIR) region with spatial and spectral responsive capabilities is a challenging and long-sought task for applications, such as multispectral adaptive camouflage and anti-counterfeiting. Here, a multispectral responsive metasurface is demonstrated that enables independent modulation of MIR thermal emission while maintaining robust, spatially directional control of NIR laser reflections. This metasurface simultaneously achieves superior ultralow specular reflectivity of 0.049 (0.8–1.2 µm) and high thermal emission regulation capability of 0.51 (8–13 µm), attributed to NIR reflection splitting and a photonically amplified metal-insulator transition, respectively. The metasurface's exceptional capability to realize temperature-invariant NIR laser and dynamic MIR camouflage is experimentally proved under significant fluctuating thermal environments, superior to existing laser-IR-compatible camouflage technologies. Dual-mode information anti-counterfeiting is further demonstrated through independent channels for detection angles and temperature responses. This work provides a new pathway for stimulus-responsive materials with spatial and spectral modulation toward diverse multispectral application scenarios.

A multifunctional interfacial molecular bridging strategy is proposed, for the first time, to address the upper interfacial issues of inverted PSCs by stabilizing the upper interface between perovskites and PCBM electron transport layer (ETL), passivating interfacial defects, and improving the energy band alignment.

Abstract

Interface engineering in inverted perovskite solar cells (PSCs) faces critical challenges arising from nonideal interfacial contact, defect accumulation, impeded carrier transport, and energy-level misalignment between the perovskite and electron transport layer, for example, phenyl-C61-butyric acid methyl ester (PCBM). These interfacial deficiencies collectively induce nonradiative recombination and degrade device stability. Herein, a multifunctional interfacial molecular bridging strategy using (benzhydrylthio)acetic acid (DSA) addresses the upper interfacial issues of inverted PSCs, achieving three synergistic roles. 1) Interfacial stabilization. A stable molecular-bridging layer is constructed with DSA at the perovskite/PCBM interface through carboxylate–Pb2⁺ coordination bonds, along with π–π stacking interactions between DSA and PCBM. 2) Defect passivation. Multiple active sites in DSA molecules, such as thioether and carboxylic acid groups, can synchronously achieve chemical passivation with undercoordinated Pb2+ sites. 3) Energy band alignment: DSA induces n-type band bending through electron donation by the thioether, reducing the work function and enhancing the electron-extraction kinetics. As a result, DSA-treated devices achieve a champion power conversion efficiency of 26.08% along with an open-circuit voltage loss of only 53 mV. Finally, the DSA-treated devices demonstrate remarkable operational stability, retaining 96% of the initial efficiency after being tracked at the maximum power point for 2000 h.

This work pushes the boundaries of epitaxy by achieving all-group-IV semiconductor heterostructures and extensive characterization. The alloys open new research topics in material properties investigation for next-generation electronic and optoelectronic device technologies.

Abstract

The successful demonstration of (Si)Ge1-xSnx alloys as direct-gap materials for infrared lasers has driven intense research on group IV-based devices for nanoelectronics, energy harvesting, and quantum computing applications. The material palette of direct-gap group-IV alloys can be further extended by introducing carbon to fine-tune their structural and electronic properties, significantly expanding their functionality. This work presents heteroepitaxial growth of C(Si)GeSn alloys using an industry-standard reduced-pressure chemical vapor deposition reactor. The introduction of CBr4 as a precursor enables controlled incorporation of C atoms (<1 at.%) into the epilayer lattice, while simultaneously increasing the Sn content in the CGeSn alloy up to ≈18 at.%. Carbon plays a key role in modulating strain, stabilizing the crystal structure, and influencing material properties. By leveraging alloying and strain engineering, quaternary CSiGeSn bulk layers and CGeSn/GeSn heterostructures are epitaxially grown. The impact of C incorporation on optical emission is investigated in LEDs based on CGeSn/GeSn multiple quantum wells, demonstrating enhanced near-infrared emission at 2.54 µm, which is sustained up to room temperature.

Smart materials and biomedical devices are increasingly used to overcome limitations in extracellular vesicle (EV) delivery. This review highlights recent advances in surface modification, exogenous and endogenous stimuli-responsive systems, and device-assisted strategies including scaffolds, microneedles, hydrogels, and microfluidic platforms, to achieve precise, efficient, and targeted EV-based therapeutic delivery.

Abstract

Extracellular vesicles (EVs) are vesicle-like structures secreted by various cell types, playing a crucial role in cell communication. As an efficient and safe therapeutic carrier, EVs offer new insights and methods for disease treatment and drug development due to high stability, low immunogenicity, and broad resources. However, current applications on EV-based delivery systems are still challenging, and additional strategies are needed to achieve precise and targeted delivery, enhance stability and safety, and avoid unnecessary immune reactions or side effects. This review summarizes the latest progress in using smart materials or devices to enhance EV delivery, aiming to provide a reference for designing novel and efficient EV-based targeted delivery strategies.

Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D5EE01162K, PaperYuan Gao, Lin-Yong Xu, Xingyu Chen, Biao Xiao, Wei Gao, Jianlong Xia, Rui Sun, Jie Min
Optimizing the nanoscale morphology of the active layer is critical for enhancing photovoltaic performance and operational stability in all-small-molecule organic solar cells (all-SMOSCs). However, controlling domain size and phase separation...
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Nature Materials, Published online: 12 June 2025; doi:10.1038/s41563-025-02259-x

The authors use nitrogen-vacancy centre magnetometry to explore layer number and magnetic field evolution of ferromagnetic and antiferromagnetic domains in the A-type antiferromagnet CrPS4.