Digital Light Processing 3D Printing Research Articles

Electrolyte-supported solid oxide fuel cells with ultra-thin honeycomb structure prepared by digital light processing 3D printing technology

A significant challenge in electrolyte-supported solid oxide fuel cells (SOFCs) pertains to the substantial thickness of the electrolyte, resulting in elevated operational temperatures that hinder commercial viability. In this research, we utilized digital light processing (DLP) 3D printing technology to fabricate ultra-thin honeycomb electrolyte-supported SOFCs and subsequently evaluated their performance. Through the use of ultraviolet absorbers, we achieved a shallow curing depth (60.3 μm), which facilitated the creation of ultra-thin electrolyte samples. We investigated the mechanical properties of electrolytes with various honeycomb structures, finding that the square honeycomb structure exhibited the highest mechanical integrity, with an average failure load of 1.01 N. Finally, we assessed the electrochemical performance, observing a substantial power density of 215.4 mW/cm2, representing a twofold increase compared to the 114 mW/cm2 achieved by the same method in a flat primary cell.

Digital Light Processing 3D‐Printed Multilayer Dielectric Elastomer Actuator for Vibrotactile Device

AbstractDielectric elastomer actuators (DEAs) have emerged as promising components in the field of soft robotics. Multilayer DEAs can enhance the output performance compared to single‐layer DEAs, but the common layer‐by‐layer stacking methods are time‐consuming and likely susceptible to concerns about frequent dielectric breakdown. Herein, the one‐piece multilayer DEAs are directly fabricated via the digital light processing (DLP) 3D printing method, taking advantage of the precise and intricate printed structure. The study also focuses on the adjustable DLP printable resin formulation, aiming to achieve a DLP printed polyurethane acrylate (PUA)‐based dielectric elastomer (DE) material that exhibits desirable characteristics, such as an appropriate dielectric constant, modulus, and minimal hysteresis loss. The non‐pre‐stretch DLP‐printed cylindrical DEA demonstrates a significant blocked force of 270 mN and maintains 45% actuation performance at a frequency of 100 Hz, attributed to both the printed multilayer structure and the optimized formulation of the DE material. Moreover, the feasibility of DLP‐printed DEAs as vibrotactile devices is demonstrated. This work has advanced the development of rapid and efficient fabrication methods of multilayer DEAs using DLP printing, with enhanced force output and attractive applications in robotics and haptic interfaces.

Fabrication of Ceramic-Polymer Piezo-Composites with Triply Periodic Minimal Interfaces via Digital Light Processing

The geometry of the phase interface in co-continuous piezoelectric composites is critical in improving their piezoelectric properties. However, conventional co-continuous piezoelectric composites are mostly simple structures such as wood stacks or honeycombs, which are prone to stress concentrations at the joints, thus reducing the fatigue service performance and force–electric conversion efficiency of piezoelectric composites. Such simple structures limit further improvements in the overall performance of co-continuous piezoelectric composites. In this study, based on the digital light processing 3D printing method, we investigated the influence of three different structures–the gyroid, diamond, and woodpile interfaces–on the piezoelectric and mechanical properties of co-continuous ceramic/polymer piezoelectric composites. These findings demonstrate that the gyroid and diamond interfaces outperformed the ceramic skeleton of the woodpile interface in terms of both mechanical and electrical properties. When the ceramic volume percentage was 50%, the piezo-composite of the gyroid surface exhibited the greatest hydrostatic figure of merit (HFOM), reaching 4.23×10−12 Pa−1, and its piezoelectric coefficient (d33) and relative dielectric constant (εr) reached 115 pC/N and 748, respectively. The research results lay the foundation for the application of co-continuous piezoelectric composites in underwater communication and detection.

Self‐Powered Integrated Tactile Sensing System Based on Ultrastretchable, Self‐Healing and 3D Printable Ionic Conductive Hydrogel

AbstractSelf‐healing ionic conductive hydrogels have shown significant potential in applications like wearable electronics, soft robotics, and prosthetics because of their high strain sensitivity and mechanical and electrical recovery after damage. Despite the enormous interest in these materials, conventional fabrication techniques hamper their use in advanced devices since only limited geometries can be obtained, preventing proper conformability to the complexity of human or robotic bodies. Here, a photocurable hydrogel with excellent sensitivity to mechanical deformations based on a semi‐interpenetrating polymeric network is reported, which holds remarkable mechanical properties (ultimate tensile strain of 550%) and spontaneous self‐healing capabilities, with complete recovery of its strain sensitivity after damages. Furthermore, the developed material can be processed by digital light processing 3D printing technology to fabricate complex‐shaped strain sensors, increasing mechanical stress sensitivity with respect to simple sensor geometries, reaching an exceptional pressure detection limit below 1 Pa. Additionally, the hydrogel is used as an electrolyte in the fabrication of a laser‐induced graphene‐based supercapacitor, then incorporated into a 3D‐printed sensor to create a self‐powered, fully integrated device. These findings demonstrate that by using 3D printing, it is possible to produce multifunctional, self‐powered sensors, appropriately shaped depending on the various applications, without the use of bulky batteries.

Polyurethane Acrylate Oligomer (PUA) Microspheres Prepared Using the Pickering Method for Reinforcing the Mechanical and Thermal Properties of 3D Printing Resin

Some photosensitive resins have poor mechanical properties after 3D printing. To overcome these limitations, a polyurethane acrylate oligomer (PUA) microsphere was prepared using the Pickering emulsion template method and ultraviolet (UV) curing technology in this paper. The prepared PUA microspheres were added to PUA-1,6-hexanediol diacrylate (HDDA) photosensitive resin system for digital light processing (DLP) 3D printing technology. The preparation process of PUA microspheres was discussed based on micromorphology, and it was found that the oil-water ratio of the Pickering emulsion and the emulsification speed had a certain effect on the microsphere size. As the oil-water ratio and the emulsification speed increased, the microsphere particle size decreased to a certain extent. Adding a suitable proportion of PUA microspheres to the photosensitive resin can improve the mechanical properties and thermal stability. When the modified photosensitive resin microsphere content was 0.5%, the tensile strength, elongation at break, bending strength, and initial thermal decomposition temperature were increased by 79.14%, 47.26%, 26.69%, and 10.65%, respectively, compared with the unmodified photosensitive resin. This study provides a new way to improve the mechanical properties of photosensitive resin 3D printing. The resin materials studied in this work have potential application value in the fields of ceramic 3D printing and dental temporary replacement materials.

Block copolymer additives for toughening 3D printable epoxy resin

We explore the potential for using a brush-coil triblock copolymer to enhance the mechanical properties of epoxy resin for 3D printing applications. Epoxy resins are widely used in structural material and adhesive and have great potential for 3D printing. However, the highly brittle nature of epoxy resins requires the use of large concentrations of toughening agents that pose significant challenges in meeting rheological requirements of 3D printing. We report a reactive brush-coil block copolymer with three distinct blocks that can phase separate and chemically crosslink with the base epoxy resin to form spherical aggregates. Detailed scanning electron microscopy imaging shows that these aggregates can arrest and deflect cracks during propagation and can synergistically strengthen (∼ 1.5×) and toughen (∼ 2×) the epoxy resin with even 1 wt% of the BCP additive to the base resin. Importantly, both the modulus and the glass transition temperatures are preserved. Direct ink writing (DIW) and digital light processing (DLP) 3D printing of the modified resins also shows the same strengthening and toughening effects seen in mold-cast samples, demonstrating its compatibility with 3D printing processes. These findings suggest that brush-coil triblock copolymers additives at very low concentrations can synergistically improve the mechanical properties of epoxy resin for 3D printed parts.

The assessment of permeability of biological implant structure using DLP-manufactured TPMS lattice physical models

This paper embarks on a comprehensive investigation into the permeability of a biological implant structure. The present study focuses on a gyroid lattice structure, miming the intricate architecture of trabecular bone within the human body. The approach allowed the identification of the structure with optimal permeability via fluid flow through experimental testing of TPMS structures prepared using Digital Light Processing (DLP) 3D printing. These structures serve as experimental models for assessing fluid flow permeability. Radial permeative flow is the central phenomenon of interest, and its behavior is analyzed in relation to variables such as porosity and viscosity. Experimental findings are meticulously compared with numerical predictions to achieve an understanding of the permeability properties. The resulting discrepancies are critically examined and discussed, shedding light on potential areas for further refinement in implant design and fabrication processes. This research represents a significant contribution to the burgeoning field of bioengineering, as it offers a novel approach to evaluating implant structures, particularly optimizing permeability.

Preparation of high performance dense Al2O3 ceramics by digital light processing 3D printing technology

The incorporation of a significant amount of organic materials in the fabrication process of Al2O3 ceramics using digital light processing (DLP) 3D printing technology leads to a noticeable reduction in mechanical properties compared to those prepared using traditional methods. To enhance its mechanical performance of Al2O3 ceramics, the addition of MgO and MgO-Y2O3 sintering additives, along with a three-step curing method, has resulted in significant improvements. Al2O3 ceramics fabricated with the addition of MgO exhibited a flexural strength of 454.2 MPa, Vickers hardness of 20.24 GPa and apparent porosity of 0.15 %. Similarly, the addition of MgO-Y2O3 yielded Al2O3 ceramics with a flexural strength of 491.6 MPa, Vickers hardness of 20.91 GPa, and apparent porosity of 0.11 %. These values exceed the typical flexural strength of Al2O3 ceramics prepared using traditional methods. This research provides a fundamental basis for the production of high performance, dense, and complex shaped Al2O3 ceramics using DLP 3D printing technology.

Experiment Investigation of the Compression Behaviors of Nickel-Coated Hybrid Lattice Structure with Enhanced Mechanical Properties.

The lattice metamaterial has attracted extensive attention due to its excellent specific strength, energy absorption capacity, and strong designability of the cell structure. This paper aims to explore the functional nickel plating on the basis of biomimetic-designed lattice structures, in order to achieve higher stiffness, strength, and energy absorption characteristics. Two typical structures, the body-centered cubic (BCC) lattice and the bioinspired hierarchical circular lattice (HCirC), were considered. The BCC and HCirC lattice templates were prepared based on DLP (digital light processing) 3D printing. Based on this, chemical plating, as well as the composite plating of chemical plating followed by electroplating, was carried out to prepare the corresponding nickel-plated lattice structures. The mechanical properties and deformation failure mechanisms of the resin-based lattice, chemically plated lattice, and composite electroplated lattice structures were studied by using compression experiments. The results show that the metal coating can significantly improve the mechanical properties and energy absorption capacity of microlattices. For example, for the HCirC structure with the loading direction along the x-axis, the specific strength, specific stiffness, and specific energy absorption after composite electroplating increased by 546.9%, 120.7%, and 2113.8%, respectively. The shell-core structure formed through composite electroplating is the main factor for improving the mechanical properties of the lattice metamaterial. In addition, the functional nickel plating based on biomimetic structure design can further enhance the improvement space of mechanical performance. The research in this paper provides insights for exploring lighter and stronger lattice metamaterials and their multifunctional applications.

Comparison of cell casted and 3D-printed plastic scintillators for dosimetry applications.

Currently, the most used methods of plastic scintillator (PS) manufacturing are cell casting and bulk polymerisation, extrusion, injection molding, whereas digital light processing (DLP) 3D printing technique has been recently introduced. For our research, we measured blue-emitting EJ-200, EJ-208, green-emitting EJ-260, EJ-262 cell cast and two types of blue-emitting DLP-printed PSs. The light output of the samples, with the same dimension of 10mm × 10mm × 10mm, was compared. The light output of the samples, relative to the reference EJ-200 cell-cast scintillator, equals about 40-49 and 70-73% for two types of 3D-printed, and two green-emitting cell-casted PSs, respectively. Performance of the investigated scintillators is sufficient to use them in a plastic scintillation dosemeter operating in high fluence gamma radiation fields.

Elastic and dimensional properties of newly combined 3D-printed multimaterials fabricated by DLP stereolithography

In the field of stereolithography 3D printing, the portfolio of commercially available photopolymers has burgeoned. Each material family possesses its individual properties. However, corresponding products with specific requirements remain a major challenge. This gap could be filled by combining existing materials. This study aimed to predict Young’s modulus of the specimen manufactured by combining multiple materials using digital light processing (DLP), a subtype of stereolithography. It also aimed to investigate the effects of the printing process on the geometry and mechanical properties of such 3D-printed multimaterials. Using a DLP 3D printer, samples were produced from commercially available pure and mixed materials, and half of the samples underwent post-printing curing. Three-point bending tests were performed to determine the elastic modulus of the samples. The elastic properties have been compared to linear interpolation using the properties of the primary materials. The measurements showed that Young’s modulus ranged from 1.6 GPa to 2.2 GPa for the post-cured materials, with the mixed materials fitting well with the linear interpolation approach. For eight out of nine sample sets, the prediction was within the range of the measurements. In the case of as-printed samples, the elasticity of the primary materials ranged from 0.4 GPa to 0.9 GPa, but all of the mixed materials showed a stiffer behavior than the linear interpolation prediction, up to 57% above the prediction. The dimensions of the printed specimen were measured, and groups of different geometrical deviations were identified. These were analyzed with regard to the printer system and material mixture. In conclusion, this study shows and discusses the effects of the printing process on mechanical and dimensional properties of specimens fabricated using a stereolithographic 3D printer from multiple commercially available primary materials. It discusses a process for predicting the elastic properties of these multimaterials and selecting the mixing ratios to achieve specifically desired properties.

Simple Non-Equilibrium Atmospheric Plasma Post-Treatment Strategy for Surface Coating of Digital Light Processed 3D-Printed Vanillin-Based Schiff-Base Thermosets.

A simple non-equilibrium atmospheric plasma post-treatment strategy was developed for the surface coating of three-dimensional (3D) structures produced by digital light processing 3D printing. The influence of non-equilibrium atmospheric plasma on the chemical and physical properties of vanillin-derived Schiff-base thermosets and the dip-coating process was investigated and compared to the influence of traditional post-treatment with UV-light. As a comparison, thermosets without post-treatment were also subjected to the coating procedure. The results document that UV post-treatment can induce the completion of the curing of the printed thermosets if complete curing is not reached during printing. Conversely, the plasma post-treatment does not contribute to the curing of the thermoset but causes some opening of the imine bonds and the regeneration of aldehyde functions. As a consequence, no great differences are observed between the not post-treated and plasma post-treated samples in terms of mechanical, thermal, and solvent-resistant properties. In contrast to the UV post-treatment, the plasma post-treatment of the thermosets induces a noticeable increase of the thermoset hydrophilicity ascribed to the reformation of amines on the thermoset surface. The successful coating process and the greatest uniformity of the lignosulfonate coating on the surface of plasma post-treated samples are considered to be due to the presence of these amines and aldehydes. The investigation of the UV shielding properties and antioxidant activities documents the increase of both properties with the increasing amount and uniformity of the formed coating. Interestingly, evident antioxidant properties are also shown by the noncoated thermosets, which are deduced to their chemical structures.

4D Printable Salicylic Acid Photopolymers for Sustained Drug Releasing, Shape Memory, Soft Tissue Scaffolds.

3D printing of pharmaceuticals offers a unique opportunity for long-term, sustained drug release profiles for an array of treatment options. Unfortunately, this approach is often limited by physical compounding or processing limitations. Modification of the active drug into a prodrug compound allows for seamless incorporation with advanced manufacturing methods that open the door to production of complex tissue scaffold drug depots. Here we demonstrate this concept using salicylic acids with varied prodrug structures for control of physical and chemical properties. The role of different salicylic acid derivatives (salicylic acid, bromosalicylic allyl ester, iodosalicylic allyl ester) and linker species (allyl salicylate, allyl 2-(allyloxy)benzoate, allyl 2-(((allyloxy)carbonyl)oxy)benzoate) were investigated using thiol-ene cross-linking in digital light processing (DLP) 3D printing to produce porous prodrug tissue scaffolds containing more than 50% salicylic acid by mass. Salicylic acid photopolymer resins were all found to be highly reactive (solidification within 5 s of irradiation at λ = 405 nm), while the cross-linked solids display tunable thermomechanical behaviors with low glass transition temperatures (Tgs) and elastomeric behaviors, with the carbonate species displaying an elastic modulus matching that of adipose tissue (approximately 65 kPa). Drug release profiles were found to be zero order, sustained release based upon hydrolytic degradation of multilayered scaffolds incorporating fluorescent modeling compounds, with release rates tuned through selection of the linker species. Cytocompatibility in 2D and 3D was further demonstrated for all species compared to polycarbonate controls, as well as salicylic acid-containing composites (physical incorporation), over a 2-week period using murine fibroblasts. The use of drugs as the matrix material for solid prodrug tissue scaffolds opens the door to novel therapeutic strategies, longer sustained release profiles, and even reduced complications for advanced medicine.

Digital Light Processing 3D Printing of Isosorbide- and Vanillin-Based Ester and Ester-Imine Thermosets: Structure-Property Recyclability Relationships.

Four isosorbide-based photocurable resins were designed to reveal correlations between the composition and chemical structure, digital light processing (DLP) three-dimensional (3D) printability, thermoset properties, and recyclability. Especially, the role of functional groups, i.e., the concentration of ester groups vs the combination of ester and imine functionalities, in the recyclability of the resins was investigated. The resins consisted of methacrylated isosorbide alone or in combination with methacrylated vanillin or a flexible methacrylated vanillin Schiff-base. The composition of the resins significantly affected their 3D printability as well as the physical and chemical properties of the resulting thermosets. The results indicated the potential of methacrylated isosorbide to confer rigidity to thermosets with some negative effects on the printing quality and solvent-resistance properties. An increase in the methacrylated vanillin concentration in the resin enabled us to overcome these drawbacks, leading, however, to thermosets with lower thermal stability. The replacement of methacrylated vanillin with the methacrylated Schiff-base resin decreased the rigidity of the networks, ensuring, on the other hand, improved solvent-resistance properties. The results highlighted an almost complete preservation of the elastic modulus after the reprocessing or chemical recycling of the ester-imine thermosets, thanks to the presence of two distinct dynamic covalent bonds in the network; however, the concentration of the ester functions in the ester thermosets played a significant role in the success of the chemical recycling procedure.

3D Printing of LuAG:Ce transparent ceramics for laser-driven lighting

The fabrication of transparent ceramics with freely designed geometries via 3D printing represents a paradigm shift in molding processes. The application of luminescent transparent ceramics (LTCs) in high-power laser-driven solid-state lighting has been significantly limited by traditional molding methods. Herein, dense cerium activated lutetium aluminum garnet (LuAG:Ce) transparent ceramics with good light transmittance (∼40%) and complex structures were successfully fabricated using a digital light processing 3D printing method assisted by vacuum sintering. We developed an ink with a high solid content (∼50 vol%) and good shear thinning property, and the optimal dye content (0.002 wt%) and exposure dose (80 mJ cm−2) to achieve 50 μm high-resolution printing were determined. A superhemispherical ceramic device with a convex curvature radius (R) of 11 mm, a concave curvature radius (r) of 10 mm, and a thickness of 1 mm was printed and sintered, which exhibited excellent laser-driven lighting properties and a high laser fluence threshold (19.22 W mm−2) owing to the special structure of surface guide grooves formed by 3D printing. Optical components prepared using 3D-printed LuAG:Ce LTCs with excellent physical and chemical properties have promising applications in next-generation high-power laser-driven solid-state lighting devices.

Universal approach for developing reprocessable and reprintable plant oil-based resins for digital light processing 3D printing

Recently, researchers have shown great interest in the development of biobased and reprintable 3D printing materials for sustainable 3D printing. Herein, a method for developing plant oil (PO)-based digital light processing (DLP) printing resins that are both reprocessable and reprintable is proposed. Biobased UV-curable monomers (POPITs) containing dynamic hindered urea bonds (HUBs) from POs were synthesized via the thiol-ene click reaction. A range of DLP printing resins (POPIT-I) with high biobased content (52.6%–58.1%) were prepared by blending POPITs with the biobased dilute monomer isobornyl acrylate. These resins demonstrated good mechanical and thermal properties (e.g., tensile strength: 45.1–49.5 MPa and Tg: 74–92 °C), as well as high DLP printing quality. Reprocessable DLP printing was employed to fabricate large-volume parts through the dissociation and reorganization of HUBs, thereby reducing printing difficulty and printing time. Additionally, a powder blending and modification method was used to recycle and reprint printed materials. The printing materials, including printed green parts and discarded supporting materials, were milled into micron-sized powders and then blended with POPIT-I to prepare the powder blending resins. The milled powders in the powder blending resins were further modified by 2-(tert-butylamino) ethyl methacrylate to prepare reprinting resins. This process resulted in the grafting of C = C onto the powder surface, which eliminated heterogeneity between the powders and POPIT-I. The mechanical and thermal properties of the reprinting resins were comparable with those of POPIT-I even after three rounds of recycling. Furthermore, the reprinting method reported here is applicable to other dynamic covalent bond-based 3D printing systems.

Ceramic bodies without warping using epoxide–acrylate hybrid ceramic slurry for photopolymerization‐based 3D printing

AbstractTo be able to produce ceramic bodies with complex shapes without interlayer delamination and warping through vat photopolymerization‐based 3D printing techniques, photosensitive ceramic slurries should be studied to prepare 3D printed green and sintered bodies. In this study, we developed dual curable acrylate–epoxide ceramic slurries for digital light processing (DLP) 3D ceramic printing. The dual curing process of the slurries is a combination of photo‐radical polymerization of acrylate and thermal cationic polymerization of cyclo‐aliphatic epoxide. The green bodies prepared by dual curing of the slurries showed higher fracture strength and better adhesion between layers and between starting particles and binder polymer in comparison to acrylate‐based green body. These advantages were due to higher crosslinking density of the binder matrix and hydrogen bonding by hydroxyl groups from epoxide ring opening. The green and sintered bodies printed with improved slurry and DLP 3D printer had flat shape without warping unlike those from acrylate‐based bodies. Moreover, the distribution of inter‐particle necking in the sintered body was uniform and the interface boundary between layers was not observed. This is because of excellent uniformity of the dual cured acrylate–epoxide polymer matrix (uniform crosslinking density in layers) in the green body and hydroxyl groups generated by epoxy ring opening.

Biobased vitrimer synthesized from 2-hydroxy-3-phenoxypropyl acrylate, tetrahydrofurfuryl methacrylate and acrylated epoxidized soybean oil for digital light processing 3D printing

The development of sustainable biobased vitrimeric materials is critical for the environment. Herein, UV-curable resins composed of the monomers derived from glycerol, soybean oil, and hemicellulose have been designed and applied in digital light processing (DLP) 3D printing. The use of hemicellulose-derived monomer tetrahydrofurfuryl methacrylate for resins can increase the tensile strength that is used to calculate the reprocessability efficiency. The vitrimeric properties of the resulting polymers such as shape memory, weldability, repairability, and reprocessability have been investigated. The most suitable resin for DLP 3D printing containing a sufficient amount of hydroxyl and ester groups that are essential in transesterification reactions has been selected according to the results of the real-time Fourier transform infrared spectroscopy and real-time photorheometry measurements. By activating dynamic transesterification reactions at elevated temperatures, the 3D printed samples exhibited shape memory, repairability, and reprocessability properties. A recovery ratio of 100 %, repairability with improved tensile strength by 2 times, and a recycling efficiency of 344 % was reached by incorporating tetrahydrofurfuryl methacrylate into the resins. The recycling efficiency achieved is 10 times higher compared to a similar vitrimer based on glycerol and soybean oil.

Digital light processing 3D printing of Hydrochlorothiazide with modified release

Digital light processing 3D printing of Hydrochlorothiazide with modified release

3D-printed polyacrylamide-based hydrogel polymer electrolytes for flexible zinc-ion battery

Zinc ion batteries (ZIBs) are a highly cost-effective and safe option for electrochemical energy storage, particularly suited for flexible wearable devices. However, the development of hydrogel polymer electrolytes (HPEs) for ZIBs using 3D printing technology presents challenges in terms of performance, stability, and durability. The purpose of this study is to address these challenges by creating 3D-printed flexible HPEs with varying porosity from polyacrylamide (PAM) using digital light processing (DLP) 3D printing. The electrochemical properties of the 3D-printed HPEs were compared to conventional casted HPEs. The 3D printed HPEs exhibited improved electrochemical performance, especially in ionic conductivity (28.10 mS cm−1, equivalent to the current conventional HPEs). Higher porosity in the 3D printed HPEs enhanced electrolyte absorption and facilitated Zn2+ ions diffusion, as confirmed by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) results. Furthermore, galvanostatic charge-discharge (GCD) measurements demonstrated that the 3D-printed PAM hydrogel electrolyte with 40% porosity achieved a specific capacity of 161.4 mAh g−1 at 0.1 A g−1. The findings validate the potential of the 3D-printed PAM hydrogel as a flexible HPE for ZIBs. The customized design structure of the 3D-printed HPEs enabled improved electrochemical properties, surpassing the limitations of conventional casted HPEs.