Novel Method of Synthesis for MXene/LIG Nanocomposites via Laser Fabrication Technique for Enhanced Performance in Energy Storage Applications

The integration of surface-regular micro/nanostructured electrodes within a limited footprint area is promising to enhance the electrochemical performance of planar micro-supercapacitors (P-MSCs), while developing simple yet efficient manufacturing methods for such electrodes remains a challenge. Here, we propose a universal strategy combining femtosecond laser plasma lithography with spatial light modulation (SLM-FPL), fabricating well-ordered sub-wavelength micro/nanostructured electrodes of interdigital P-MSCs (SEP-MSCs) on graphene oxide (GO) films. Achieving 500/50 µm finger widths/spacings and 680 nm internal grating periods, this method enables device densities >25 units inch−2 with processing efficiency orders of magnitude higher than conventional laser direct writing. Further performance optimizations via wettability modification, electric field engineering, and hybrid composites (GO-MXene/COF) yield outstanding specific capacitance (~41.4 F cm−3) and cycling stability (93% retention over 5000 cycles), supporting applications in flexible sensors and compact power supplies. This SLM-FPL technology shows strong potential for high-performance, spatially efficient SEP-MSCs in next-generation integrated systems.

Laser fabrication of flexible electrodes for bioelectronics.

High-entropy alloy nanoparticles (HEA NPs) constitute an interesting material class with high potential as heterogeneous catalysts due to their exceptional compositional and structural tunability and the complex interplay of different element-specific surface sites. Laser ablation in liquids (LAL) is a kinetically controlled synthesis method that allows the generation of colloidal HEA NPs. With CrMnFeCoNi-NPs, a facile control of the NP phase structure, switching between crystalline and amorphous via applied laser pulse duration, has been previously reported, attributed to the different particle solidification times and metalloidic carbon incorporation pathways. However, neither the replacement of the oxygen-affine Mn by the sp2-carbon coupling element Cu, nor the transferability of the pulsed laser fabrication process from bulk target to micropowder feedstock processing, has been studied. In the present work, we use scanning transmission electron microscopy, equipped with energy-dispersive X-ray spectroscopy (STEM-EDX), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and X-ray diffraction (XRD) to demonstrate the transferability of internal phase structure tunability to the CrFeCoNiCu alloy and confirm ns- and ps-pulsed LAL yielding amorphous and crystalline HEA NPs, respectively, with diameters of 10-40 nm. Furthermore, we examine the generation of CrMnFeCoNi and CrFeCoNiCu nanoparticles by scalable, fully continuous ns-pulsed microparticle laser fragmentation in liquid (MP-LFL) using a high-power UV-laser and find the emergence of amorphous phase structures only in the Cu-containing nanoparticles, a phenomenon we attribute to copper-catalyzed carbon incorporation into the HEA NPs. These studies are complemented by a detailed characterization of the surface electrochemistry of the HEA NPs via alkaline cyclic voltammetry (CV) and elemental compositions in surface-near volumes, quantified by X-ray photoelectron spectroscopy (XPS). We elucidate that primarily the chemical composition (Mn vs. Cu) and, only to a lower extent, the phase structure (amorphous vs. crystalline) determine the surface potential, electrochemical stability upon multiple CV cycling, and surface element distribution of the particles. Finally, the activity of the HEA NPs in the oxygen evolution reaction (OER) is evaluated via linear sweep voltammetry (LSV), where we find amorphous CrMnFeCoNi HEA NPs to be more active (lower overpotential, higher current density) than their crystalline counterparts, motivating future application-focused work and transfer to other material systems and relevant reactions.

Ultrafast Laser Fabrication Technology for Liquid Metal Flexible and Stretchable Electrodes and Its Application in Pressure Sensing (Invited)

One-step laser fabrication of a P-doped 3D porous graphene electrode for on-site detection of promethazine.

This work presents a visual growth strategy based on water-induced phase transitions, which enables real-time tracking and structural regulation of Cs4PbBr6-to-CsPbBr3 microcrystal transformation under ambient conditions without the need for high-energy beams or vacuum. Driven by the difference in the dissolution rates of CsBr and PbBr2 in water, the slow progression of the reaction interface allows clear observation of crystal morphology evolution under a conventional fluorescence microscope. The microcrystals obtained through strategy possess highly regular structural morphology and superior optical properties. In the experiments, micron-scale-wire exhibiting size-dependent polarized emission and bulk-microcrystals supporting multimode lasing emission were successfully constructed. Further analysis revealed the significant influence of crystal size on excited-state dynamics, cavity mode selectivity, and emission characteristics, thereby establishing a direct link between structural visual regulation and functional photon output. This work delivers mechanistic insights and experimental evidence for controllable fabrication of low-threshold lasers and polarized light-emitting devices.

Double-beam femtosecond laser fabrication of dual period micro-nanostructures for robust anti-icing surfaces

Predicting ablation-assisted nanosecond laser fabrication of glass optical diffusers by machine learning

Laser fabrication of Ti stent and facile MEMS flow sensor integration for implantable respiration monitoring

This paper presents the design and fabrication of a 1.65 μm tapered semiconductor laser based on an InGaAlAs multiple quantum well structure (grown) on InP. Through theoretical modeling and parametric optimization simulations, it was established that an etching depth of 0.8 μm for the ridge waveguide and a taper angle of 6° effectively confine the optical field and suppress high-order mode lasing. Based on these optimized parameters, a tapered semiconductor laser with a ridge width of 2 μm and a cavity length of 2000 μm was successfully fabricated. Systematic characterization was conducted under continuous-wave operation at 25 °C. The device exhibits outstanding overall performance: a maximum continuous-wave output power of 19.3 mW, a peak wavelength of 1653 nm, a spectral line width of 0.793 nm, and a side-mode suppression ratio (SMSR) as high as 49 dB, demonstrating excellent spectral purity. Far-field measurements further reveal that at an injection current of 30 mA, the vertical and horizontal far-field divergence angles are 41.02° and 15.26°, respectively, with a well-defined Gaussian beam profile. This study provides an effective technical approach for the design and fabrication of high-performance semiconductor lasers in the 1.65 μm band. The developed device shows significant potential for applications in free-space optical communication, LiDAR, and gas sensing.

The biomimetic super‐slippery surface is a solid–liquid composite structure formed by infusing a low‐surface‐energy lubricant into micro‐ and nanostructured substrates. Owing to its outstanding liquid‐repellent and self‐healing capabilities, this surface holds substantial research significance and broad application potential. Femtosecond lasers, owing to their broad material compatibility, high processing precision, and excellent controllability, are considered an effective technique for the fabrication of super‐slippery surfaces. The article begins by summarizing the characteristics, fabrication principles, and current state of research on super‐slippery surfaces. It then emphasizes femtosecond laser‐based fabrication, discussing the corresponding mechanism and advantages, as well as recent advances in preparing super‐slippery surfaces on diverse substrates such as polymers, ceramics, metals, and alloys. The article also discusses the diverse applications of super‐slippery surfaces fabricated via femtosecond laser processing, including corrosion resistance, anti‐icing, antifouling, emerging fields such as biomedical engineering, blood compatibility, and controlled droplet transport. Finally, this work summarizes the key issues and challenges that remain in the femtosecond laser fabrication of super‐slippery surfaces.

Understanding the microscopic mechanism of interaction between ultrafast laser and quartz materials is vital for laser fabrication of quartz optical waveguide device. Recently, the time-dependent density functional theory (TDDFT) based on quantum mechanics becomes an effective theoretical tool to investigate the ultrafast photoexcitation dynamics in quartz. However, the role of electron cooling has not been involved in previous studies. In fact, the electron cooling as a key physical process significantly affects electron–lattice spatiotemporal evolution as well as the transient optical response of quartz. This paper employs the real-time TDDFT method to simulate the femtosecond laser irradiation of α-quartz at room temperature with a consideration of the electron cooling effect. It was found that the electron cooling increased the lattice temperature and atomic displacements within tens of femtoseconds through the electron–lattice energy transfer. Particularly, the bandgap of quartz presented a drastic reduction by up to 38%, which mainly originated from the rapid lattice structure evolution. This paper demonstrates that the electron cooling effect should not be ignored in the calculation of laser–quartz interaction because it stimulates the renormalization of electronic structure and lattice structures of quartz, which has a huge impact on optical and electrical properties of quartz materials.

Ultrafast laser fabrication of nanochannels in polymeric membranes could enable superior performance compared to conventional methods in terms of scalability, precision, and patterning controllability. However, achieving sub-100 nm features has been fundamentally limited by diffracting limits and thermal effects during laser-polymer interactions. Here, we demonstrate single-shot fabrication of bottleneck-shaped nanochannels through PET films using ultrafast Bessel beams, achieving 59 nm constrictions-a feature size well below the optical diffracting limit. This result is achieved through precise control of the thermal-affected zone and the interaction between the superficial and internal ablations. The technique additionally produces microchannels with morphological versatility. This work enables precise nanofabrication with applications in single-molecule sensing, oriented ion transport, and water treatment.

The rise of high-performance functional devices has driven significant breakthroughs in various research fields, with ultrafast laser processing offering unprecedented opportunities for advanced device fabrication. This review summarizes recent progress and future prospects for ultrafast laser in fabricating functional optical, semiconductor, and sensor devices. Central to these advances is a deeper understanding of ultrafast laser–matter interaction physics, including nonlinear optical effects, multiphoton ionization, avalanche ionization, and laser-induced plasma dynamics. These phenomena govern carrier excitation, energy deposition, and subsequent structural modification. We further review how such interactions enable controlled refractive index changes, selective ablation, and nanoscale material structuring in photosensitive, dielectric, semiconductor, and metallic substrates. Key applications are then reviewed, including ultrafast laser fabrication of optical devices (e.g., optical waveguide devices, optical data storage elements, optical elements, and artificial compound eyes, integrated photonic devices), semiconductor devices (e.g., semiconductor light-emitting devices, photodiodes, solar cells, and photodetectors), and sensors (e.g., fiber optic sensors, flexible sensors, and biochemical sensors). Recent breakthroughs showcase ultrafast laser-induced precision in device miniaturization, improved optoelectronic characteristics, and integration of complex functions (e.g., topological photonic circuits fabricated via sub-100-nm laser writing, 5D optical data storage in glass with > 1 TB/cm3 density, perovskite solar cells achieving 25.7% efficiency through laser-induced phase engineering, alongside plasmonic biosensors with 100× sensitivity enhancement, and stretchable graphene sensors for wearables). Finally, this review discusses core challenges, such as enhancing the scalability of ultrafast laser processes for industrial-scale production and optimizing laser-material interactions to improve device reliability and performance. Future efforts should address key challenges such as the limited scalability of ultrafast laser processing and the incomplete understanding of laser–matter interactions at ultrafast timescales. Integrating ultrafast lasers with AI-driven control, beam shaping, and advanced materials such as 2D heterostructures may enable smarter and more multifunctional device platforms. A unified theoretical framework is also needed to guide precise and efficient fabrication. These directions highlight critical opportunities for bridging current limitations and enabling transformative advances. While not exhaustive, this review lays a foundation for further research into the transformative potential of ultrafast laser in functional device fabrication.

Plasmonic nanoparticles (NPs) are widely utilized in various applications including sensing and imaging due to their strong localized surface plasmon resonances (LSPRs). Recently, plasmonic NP assemblies and configurations have also been explored as physical unclonable functions (PUFs) for security applications, however, many existing PUF designs face challenges such as complex fabrication processes and high costs, which complicate their implementation. This study introduces a scalable and practical approach to fabricate disordered self-assembled silver NPs for use as dual-purpose features in plasmonic devices. These nanostructures could offer multifunctionality by simultaneously serving as a functional plasmonic feature and as a potential PUF, providing an extra security layer in the device configuration. The proposed nanostructuring method could support the large-scale production of plasmonic nanostructures with desirable LSPR characteristics, essential for diverse plasmonic applications, while their structural uniqueness enables their potential exploitation as unclonable PUF fingerprints. In this work, disordered silver NPs were grown via laser annealing of silver ultrathin films with thicknesses ranging from 12.5 to 15 nm. Ultraviolet-visible spectroscopy and atomic force microscopy revealed high-intensity LSPRs and unique nanopatterns, demonstrating their potential multifunctionality.

To address the demand for efficient and compact light sources in the 1200-1250 nm spectral range for applications in biomedical imaging and nonlinear frequency conversion, this paper proposes a theoretical design and performance simulation scheme of a bismuth-doped fiber laser. A steady-state rate-equation model based on a quasi-four-level system is established, which comprehensively describes the power evolution of forward and backward pump and signal light within a linear cavity structure. The resulting two-point boundary value problem is solved numerically using MATLAB'sbvp4csolver. The simulation results indicate that the designed laser possesses excellent performance potential, clearly revealing the processes of pump attenuation and signal amplification within the cavity. The findings validate the effectiveness of the established model and quantitatively predict the feasibility of achieving high-efficiency operation from a 1200 nm bismuth-doped fiber laser. This work provides significant theoretical guidance and a design basis for the experimental fabrication, parameter optimization, and performance enhancement of fiber lasers in this spectral range.

Nanosecond laser etching combined with surface modification presents a promising method for fabricating superhydrophobic surfaces with enhanced functionality. In this study, superhydrophobicity is achieved on 7075 aluminum alloy via nanosecond laser treatment followed by lauric acid modification to reduce surface energy. Additionally, carbon black coatings derived from candle soot are applied for comparison. The impact of surface structure and the formation of underwater gas films on buoyancy is systematically explored. A composite sample with laser‐etched microstructures and soot coating demonstrated excellent superhydrophobicity. After injecting air beneath the sample to form a stable gas film, the maximum load‐bearing capacity and the deepest surface vortex are observed. Without an air film, superhydrophobic properties degraded within 3 days of immersion, while samples with gas films maintained performance for up to 20 days. A repair mechanism for the air film is also examined. Experimental results showed a 313% increase in buoyancy for treated surfaces compared to untreated ones. Characterization confirmed that the fabricated surfaces exhibit high durability, superior buoyancy, and strong wear resistance, indicating their potential for marine engineering and buoyancy‐enhancing applications.

The Mount Wudang architectural complex, recognized as a UNESCO World Cultural Heritage site, extensively utilizes green schist as the building material in its rock temple structures. Due to prolonged exposure to weathering and moisture, effective surface protection of these stones is crucial for their preservation. Inspired by the lotus leaf, femtosecond laser fabrication of bioinspired micro/nanostructures offers a promising approach for imparting hydrophobicity to stone surfaces. However, green schist is a typical heterogeneous material primarily composed of quartz, chlorite, and muscovite, and it contains metal elements, such as Fe and Ni. These pronounced compositional differences complicate laser-material interactions, posing considerable challenges to the formation of stable and uniform micro/nanostructures. To address this issue, we performed systematic femtosecond laser scanning experiments on green schist surfaces using a 100 kHz, 40 μJ laser with a 30 μm spot diameter, fabricating microgrooves under various process conditions. Surface morphology and EDS mapping analyses were conducted to elucidate the ablation responses of quartz, chlorite, and muscovite under different groove spacings (100 μm, 80 μm, 60 μm, and 40 μm) and scan repetitions (1, 2, 4, 6, 8, 10). The results revealed distinct differences in energy absorption, material ejection, and surface reorganization among these minerals, significantly influencing the formation mechanisms of laser-induced structures. Based on optimized parameters (60 μm spacing, 2-6 passes), robust and repeatable micro/nanostructures were successfully produced, yielding superhydrophobic performance with contact angles exceeding 155°. This work offers a novel strategy for interface control in heterogeneous natural stone materials and provides a theoretical and technical foundation for the protection and functional modification of green schist in heritage conservation.

The un-doped CaF2 and Dy3+ ion doped CaF2 Nanoparticles were chemically synthesized following the solution combustion method using calcium nitrate, Ca(NO3)2 (99.9%, Sigma Aldrich) as the source of calcium, NH4F (99.9%, Sigma Aldrich) as the source of fluoride and Dy2O3 (99.9%, Sigma Aldrich) as the source of dysprosium respectively. The average crystallite size of un-doped CaF2 nanoparticles was found to be 15.76nm and that of CaF2:Dy3+ nanoparticles was found to be 32.04nm. The variation of crystallite size of the samples on doping of Dy3+ ion was revealed from XRD analysis. The Rietveld refinement analysis of CaF2:Dy3+ nanoparticles has been also done to confirm the retention of cubic fluoride structure in it. The formation of Nano spheroids was also confirmed from the study of surface morphology by FESEM. The absence of impurities in the prepared powder samples was confirmed by EDAX analysis. The band gap energy of un-doped CaF2 nanoparticles was found to be 3.87eV and that of CaF2:Dy3+ nanoparticles was found to be 1.80eV. The optical study revealed the transition of band gap of CaF2 from direct to indirect band gap on doping of Dy3+ ions indicating its applicability in optoelectronics to design photodetector. The Urbach energies of CaF2 and CaF2:Dy3+nanoparticles were found to be 2.33eV and 0.15eV respectively. As the PL emission peaks of un-doped CaF2 and CaF2:Dy3+ nanoparticles were observed around 420nm and 480nm, 573nm respectively, the photoluminescence study also explored the applicability of the synthesized samples as potential material for fabrication of violet and white light laser.