Nanoscience News (<front>)

Phos-XK, a novel hydrogel electrolyte, is crafted from xanthan gum and konjac gum through physical crosslinking and targeted phosphorylation. This design balances mechanical strength and ionic conductivity, enabling Zn//MnO₂ batteries with long cycle life and high Coulombic efficiency. Its biocompatibility and biodegradability offer a sustainable solution for flexible, wearable energy storage electronics.

Abstract

Natural polymer-based hydrogel electrolytes, though biocompatible and cost-effective, often exhibit poor mechanical strength and ionic conductivity, limiting their use in high-performance energy storage. Phos-XK, a novel hydrogel electrolyte derived from xanthan gum (XG) and konjac glucomannan (KGM), has been developed via physical cross-linking and targeted phosphorylation. Specifically, physical cross-linking forms a robust 3D network that provides a stable structural foundation. Building on this, the phosphorylation process introduces phosphate monoesters (MPE) and diesters (DPE) in a precisely controlled ratio. MPE groups enhance ionic conductivity by facilitating Zn2+ desolvation and ion migration, while DPE strengthens mechanical integrity through enhanced cross-linking. These distinct roles of MPE and DPE are confirmed through both theoretical calculations and experimental results. Optimizing the phosphorylation ratio achieves a balance between mechanical strength (2.524 MPa) and ionic conductivity (20.72 mS cm−1), resulting in remarkable electrochemical performance, including an extended cycle life exceeding 3000 h and a high Coulombic efficiency of 99.45% in Zn//Cu batteries. Moreover, Phos-XK is biocompatible and biodegradable, ideal for sustainable energy storage. This work highlights the potential of bio-based materials to overcome the limitations of traditional hydrogel electrolytes and stresses the importance of molecular engineering in achieving high-performance, eco-friendly energy storage.

A PROTAC-based cuproptosis sensitizer CuS-MD@CS is developed in this work, which sensitizes cells to cuprotosis by modulating the p53 pathway through the ubiquitin-proteasome systemcan. CuS-MD@CS not only can effectively deplete endogenous glutathione but also can promote the transition from glycolysis to mitochondrial respiration, thereby enhancing cancer cells' sensitivity to cuproptosis and achieving effective therapeutic effects of cuprotosis and apoptosis.

Abstract

As an autonomous form of regulated cell death, cuproptosis depends on copper (Cu) and mitochondrial metabolism. However, the principle metabolic pathway known as glycolysis (Warburg effect) and high glutathione (GSH) levels of tumor cells inevitably lead to suboptimal efficacy in cuproptosis. Hence, depleting the endogenous GSH within tumors and shifting from glycolysis to mitochondrial respiration are crucial factors for augmenting cuproptosis. In this study, a proteolysis targeting chimera (PROTAC)-based cuproptosis sensitizer (CuS-MD@CS) is innovatively constructed, which not only can induce cuproptosis and reactive oxygen species production via copper ions but also can regulate the expression of p53 protein via PROTACs through the ubiquitin-proteasome system in tumor cells, thus achieving endogenous GSH depletion and a shift from glycolysis to mitochondrial respiration, making cancer cells more sensitive to cuproptosis. Importantly, in vitro and in vivo experiments have verified that CuS-MD@CS effectively targets A549 cells and suppresses tumor growth through cuproptosis and apoptosis, exhibiting promising therapeutic responses. The novel PROTAC-based cuproptosis sensitizer CuS-MD@CS provides a new strategy for sensitizing cuproptosis and offers new hope for effective lung cancer treatment.

In this article, the fabrication of light-emitting diodes (LED) using self-emissive bimetallic gold-copper nanoclusters (NCs) is reported. The NC-LED shows a maximum brightness of 1246 cd m−2 and the highest external quantum efficiency (EQE; 12.60%) value with pure red emission among the solution-processed and non-doped NC-based LEDs.

Abstract

Self-emissive atomically precise metal nanoclusters (NCs) are emerging as promising emissive layer material for next-generation light-emitting diodes (LEDs), thanks to their solid-state luminescence, well-defined structures, photo/thermal stability, low toxicity, and unique excited-state properties. However, achieving high external quantum efficiency (EQE) in solid-state NCs remains a formidable challenge. In this study, a highly stable bimetallic gold-copper NC forming [Au2Cu6(Sadm)6(DPPEO)2] stabilized with 1-adamantanethiol (HSadm) and 1,2-bis(diphenylphosphino)ethane (DPPE) as the primary and secondary ligands, respectively is reported. Single-crystal X-ray diffraction and spectroscopic analyses suggest that the as-synthesized NC contains one phosphine bound to gold and the second phosphine has oxidized to phosphine oxide (P═O). The presence of such P═O moieties in the NC facilitated C─H···O interactions along with C─H···π and H···H interactions between ligands, promoting rapid crystallization. Due to the exceptional photo/thermal stability and enhanced solid-state photoluminescence quantum yield (PLQY), [Au2Cu6(Sadm)6(DPPEO)2] NC is utilized to fabricate the NC-based LED (NC-LED) via the solution-processed technique, without using any additional host materials. The fabricated NC-LED shows a maximum brightness of 1246 cd m−2 and an EQE of 12.60% with a pure red emission ≈668 nm. This EQE value coupled with saturated pure red emission is the best among solution-processed and non-doped NC-LEDs, suggesting the enormous potential of the NCs for electro-optical devices.

We report a 3.2 Å cryoEM structure of functional amyloid protein FapC from Pseudomonas sp. UK4, an essential component of bacterial biofilm, which reveals a Greek key-shaped protofilament, supports bioinformatically determined motifs, nuances AlphaFold predictions, emphasizes heterogeneous cross-β stacking in amyloid cross-seeding and shows strain-dependent nanomechanical properties. FapC fibrils are intrinsically catalytic. This provides a structural foundation to design novel biomaterials.

Abstract

An essential structural component of bacterial biofilms is functional amyloid (FuA), which also has great potential as an engineerable nano-biomaterial. However, experimentally based high resolution structures of FuA that resolve individual residues are lacking. A fully experimentally based 3.2 Å resolution cryo-electron microscopy density map of the FuA protein FapC from Pseudomonas sp. UK4 is presented, which reveals a Greek key-shaped protofilament. The structure supports bioinformatic identification of conserved motifs and is broadly consistent with the AlphaFold prediction but with important modifications. Each FapC monomer consists of three imperfect repeats (IRs), with each repeat forming one cross-β layer. An array of highly conserved Asn and Gln residues with an extensive H-bonding network underpins this conserved Greek key-shape and reveals the role of heterogeneous cross-β stacking in amyloid cross-seeding. The covariation of residues in the hydrophobic core among different IRs suggests a cooperative monomer folding process during fibril elongation, while heterogeneous stacking of IRs reduces charge repulsion between layers to stabilize the monomer fold. The FapC fibrils show intrinsic catalytic activity and strain-dependent nanomechanical properties. Combined with mutagenesis data, the structure provides mechanistic insights into formation of FapC FuA from disordered monomers and a structural foundation for the design of novel biomaterials.

Nature Materials, Published online: 11 June 2025; doi:10.1038/s41563-025-02265-z

Broadband terahertz emission from a two-dimensional van der Waals ferroelectric semiconductor, NbOI2, offers opportunities towards nanoscale near-field terahertz spectroscopy and in situ probing of quantum collective excitations in two-dimensional materials.

Nature Materials, Published online: 11 June 2025; doi:10.1038/s41563-025-02257-z

While nanofluidics demonstrate unconventional properties at the nanoscale, large-scale implementation remains challenging. The authors demonstrate macroscale resonant electro-osmotic transport in asymmetric membranes for advanced water filtration applications.

Nature Nanotechnology, Published online: 11 June 2025; doi:10.1038/s41565-025-01948-7

Scrutinizing the dynamic reconfiguration mechanism of intermetallic single-atom catalysts reveals the chemical origin of the enhanced electrocatalysis performance.

Nature Nanotechnology, Published online: 11 June 2025; doi:10.1038/s41565-025-01957-6

Polymeric stabilization of photocatalysts at the gas–liquid interface enhances both the catalytic activity and stability for solar hydrogen production from plastic waste. The photocatalyst retains its performance over 2 months under harsh conditions, and scaling to 1 m2 yields a hydrogen production rate of 0.906 l per day from polyethylene terephthalate waste under natural sunlight.

The structural-colored tube is created from cholesteric liquid crystal elastomers, exhibiting uniform color changes with high strain sensitivity upon extension and inflation. The color change occurs across multiple mechanochromic modes, highlighting the influence of molecular anisotropy and tubular geometry on strain sensitivity. The tubes demonstrate reconfigurable alphabet displays and 3D photonic skins.

Abstract

Materials that exhibit varied optical responses to different modes of mechanical stimuli are attractive for complex sensing and adaptive functionalities. However, most mechanochromic materials are fabricated from films or fibers with limited actuation modes. Here, hollow tubes of a symmetric sheath are created using cholesteric liquid crystal elastomers (CLCEs) at the sub-millimeter scale. The oligomeric precursor is sheared in an elastomeric microchannel to form uniform thickness, overcoming gravity effect and Plateau-Rayleigh instability. In addition, the coloration is achieved to be faster and have higher reflectivity compared to that of solid fibers. The tube can undergo axial, circumferential, and radial strains upon extension and inflation. The combination of molecular anisotropy and geometry of the tube enables highly sensitive mechanochromic responses in both azimuthal and axial directions: inflation causes red-to-violet shift (≈220 nm) at a circumferential strain of 0.57. The inflation of a bent tube generates another mechanochromic mode with a higher sensitivity to strain. Finally, display of 26 alphabets is achieved using 5 tubes, of which the positions can be reconfigured, and curvature-dependent 3D photonic skins are demonstrated from tubes wrapped around 3D objects. The multi-mode mechanochromic tubes will find applications for soft robotics, adaptive displays, wearable sensors, and spectrometers.

The detachment behavior between the adhesives and the electrodes are always caused by significant interlayer shear stress during bending in neutral plane flexible perovskite solar cells (NP-FPSCs). A crosslinkable polymer named acrylated isoprene rubber (AIR) is introduced to form a stable network, ensuring a strong bond between the protective layer and FPSCs. The resultant NP-FPSCs demonstrate excellent mechanical stability — the most mechanically stable devices reported to date.

Abstract

The functional layers of flexible perovskite solar cells (FPSCs) are subjected to significant stress during bending, causing structural failure and declining power conversion efficiency. To alleviate stress, a neutral plane (NP) is introduced by positioning the functional layers at the center of the device, with top metal electrode encapsulated by a protective layer. However, adhesive detachment remains a critical issue during multiple bending cycles, and the underlying mechanism remains unclear. In this study, a systematic analysis of the detachment behavior in NP-FPSC reveals that commercial adhesives with high Young's modulus and low adhesion strength struggle to withstand interlayer shear stress during bending, which triggers detachment between adhesives and electrodes. To address this issue, a crosslinkable polymer acrylated isoprene rubber (AIR) is designed with long linear polyisoprene main chain and acrylate side chains, providing high flexibility and reduced chain segment movement. AIR can be crosslinked under UV irradiation to form a stable network with ultralow Young's modulus and high adhesion strength, ensuring a strong bond between the protective layer and FPSCs, constructing stable NP-FPSCs. The resultant NP-FPSCs demonstrate excellent mechanical stability, retaining 92.8% of their initial efficiency after 50 000 bending cycles at a radius of 4 mm, meeting the IEC 62715-6-3 standards.

A rapid and deep reconstruction of RuPdOx hollow nanofibers to generate RuO2/Pd heterostructure is achieved to regulate the local electronic environment of catalyst during hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR) processes. Thus the obtained material exhibits exceptional ampere-grade-current-density HER and HzOR properties, enabling significnat energy-saving H2 production performance.

Abstract

Manipulating the reconstruction of a heterostructured material is highly desirable to achieve high-performance electrocatalytic performance. Here, an in situ reconstruction of RuPdOx hollow nanofibers (HNFs) is presented to generate RuO2/Pd from both the electrochemical and chemical reconstruction processes. The reconstructed catalyst is highly efficient for both hydrazine oxidation reaction (HzOR) and hydrogen evolution reaction (HER) at industrial-grade current densities, significantly outperforming the benchmark Pt/C catalyst. Furthermore, it maintains a record-breaking durability of 500 h for HzOR at 1 A cm−2. Remarkably, with the catalyst as electrodes, a two-electrode overall hydrazine splitting (OHzS) cell is constructed, which requires only 0.263 kWh of electricity to produce 1 m3 H2 at 100 mA cm−2, significantly lower than that in overall water splitting (OWS) system (4.286 kWh m−3 H2), exhibiting an exceptional energy-saving H2 production property. Density functional theory (DFT) calculations reveal an efficient electron transfer from Pd to RuO2 at their interface from the reconstruction of RuPdOx HNFs, which regulates the local electronic environment of atoms, modulates the adsorption and desorption for intermediates, and reduces the energy barriers for enhancing the electrocatalytic process. This study offers a robust reconstruction strategy for the design of electrocatalysts that exhibit superior efficiency in energy conversion devices.

This study demonstrates that the nonlinear kinematics of origami sheets can be exploited to realize crawlers capable of multimodal locomotion under a single actuation input. In particular, it focuses on one of the simplest origami building blocks - a rigid degree-four vertex - and identifies designs that enable movement in a straight line as well as turning left or right by simply controlling the folding range of the actuated fold.

Abstract

The ancient art of origami, traditionally used to transform simple sheets into intricate objects, also holds potential for diverse engineering applications, such as shape morphing and robotics. In this study, it is demonstrated that one of the most basic origami structures–a rigid, foldable degree-four vertex–can be engineered to create a crawler capable of navigating complex paths using only a single input. Through a combination of experimental studies and modeling, it is shown that modifying the geometry of a degree-four vertex enables sheets to move either in a straight line or turn. Furthermore, it is illustrated that leveraging the nonlinearities in folding allows the design of crawlers that can switch between moving straight and turning. Remarkably, these crawling modes can be controlled by adjusting the range of the folding angle's actuation. This study opens avenues for simple machines that can follow intricate trajectories with minimal actuation.

What if disorder can be designed? This work introduces a strategy to self-assemble amorphous materials by designing bonding rules for patchy particles that suppress crystallinity and promote frustration. The designer particles nucleate a network of dodecahedral cages from the liquid, yielding a novel equilibrium amorphous phase. This approach redefines how disorder and function can be programmed at the colloidal scale.

Abstract

The ability to control self-assembly with atomic-level precision has led to remarkable advances in the rational design of crystalline materials. However, similar design strategies have yet to be developed for amorphous materials. Here, a strategy is devised for programming the self-assembly of amorphous structures by encoding frustration into the building block design. The building blocks are tailored to locally favor the formation of five-member rings and yield a network of face-sharing dodecahedral cages whose icosahedral symmetry prevents long-range order. Surprisingly, unlike geometrically frustrated glasses that form through kinetic arrest, the network nucleates spontaneously from the liquid phase, representing a novel type of thermodynamically stable disordered phase. The stabilization of this frustrated phase via programmable interactions paves the way for a new generation of disordered materials.

Irradiation rather than composition is used to induce helix/trans morphotropic phase boundary (MPB) in ferroelectric polymers. Markedly enhanced piezoelectric coefficient d 33 of -69.8 pC N−1 is achieved in ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) copolymers. This postprocessing approach is generally applicable to different ferroelectric polymer compositions and sources of irradiation, offering a scalable tool to design of ferroelectric polymers with high piezoelectric properties.

Abstract

Morphotropic phase boundary (MPB) enables a large piezoelectric effect in ferroelectric polymers. However, till now MPB has only been observed in a few polymers, which is induced by compositional tuning of the polymer composition. Here a distinct approach to design MPB in ferroelectric polymers is reported via ion irradiation. Without changing composition as required by the conventional compositional approach, the formation of helix/trans MPB in ferroelectric polymers is achieved upon increasing the irradiation dose, near which a substantially enhanced piezoelectric coefficient d 33 of -69.8 pC N−1 is observed. The effectiveness of this method is demonstrated by using different sources of irradiation and polymer compositions, which offers a general and scalable postprocessing tool to effectively improve the piezoelectric response of ferroelectric polymers.

The TiO2-coated MnO2 cathodes enhance the cycling stability and capacity of zinc-ion batteries by improving kinetics and inhibiting Mn dissolution. The multifunctional TiO2 coating forms a coherent interface with MnO2, creating an electron-enriched surface that promotes rapid electron/ion transport and proton-dominated reactions. Additionally, the coating mitigates Mn dissolution and buffers volume changes, offering a promising solution for advanced energy storage.

Abstract

Zinc-ion batteries are a promising energy storage alternative, offering safety, cost-effectiveness, and environment-friendliness. MnO2 is appealing for its high capacity and output voltage, but it suffers from slow kinetics and poor stability due to severe Mn dissolution during cycling. Here, the performance of MnO2 is enhanced by coating it with a uniform TiO2 nanolayer that incorporates oxygen vacancies. The TiO2-MnO2 heterogeneous interface results in the formation of Ti─O─Mn bonds and a reduction in the interfacial valence state, thereby leading to the creation of an interface electron-enriched region that facilitates faster electron and ion transport. This multifunctional TiO2 coating not only promotes proton-dominated electrochemical reactions and ion diffusion but also acts as a protective barrier, preventing Mn dissolution and buffering volume changes during cycling. Consequently, the MnO2@TiO2 cathode demonstrates excellent specific capacity (299 mAh g−1 at 0.1 A g−1) and cycling stability, achieving 91.4% capacity retention after 2500 cycles at 1 A g−1 and 92.7% capacity retention after 600 cycles at a low current density of 0.2 A g−1. These results outperform many previously reported manganese-based cathodes, demonstrating MnO2@TiO2’s potential as a high-performance and durable cathode material for zinc-ion batteries and advancing the development of efficient energy storage solutions.

Electrochemical reduction of low-concentration NO presents a promising avenue for NH3 production, offering a sustainable solution to environmental challenges. Cu─Co dual-sites in hollow cobalt oxide nanoboxes are developed for NO electroreduction, boasting a Faraday efficiency of 94.13% and an NH3 yield of 54.28 µg h−1 mgcat −1. A Zn-NO battery has also been successfully demonstrated for simultaneous NO elimination, NH3 generation, and power output.

Abstract

The electrocatalytic conversion of nitric oxide (NO) to ammonia (NH3) epitomizes an advanced approach in NH3 synthesis, crucial for efficiently converting low-concentration industrial NO exhaust and contributing significantly to environmental preservation. Catalyst design remains one pivotal element in addressing this challenge. Here, efficient Cu─Co dual active sites embedded in hollow cobalt oxide nanoboxes are created for the electrocatalytic low-concentration NO reduction reaction (NORR). Cu-modified cobalt oxide (Cu-Co3O4) and its heterophase interface with copper oxide (Cu-Co3O4/CuO) both exhibit over 93% Faraday efficiency for NH3 synthesis, with a yield reaching up to 59.10 µg h−1 mgcat −1 at −0.4 V versus reversible hydrogen electrode by utilizing simulated industrial NO exhaust (1 vol %) as the feedstock, surpassing those of pure cobalt oxide and some reported catalysts. Theoretical calculations and NO temperature-programmed desorption experiments demonstrate that the incorporation of Cu significantly enhances NO adsorption and reduces the energy barrier of the rate-determining step. The integration of Cu-Co3O4 and Cu-Co3O4/CuO within the cathode of the Zn–NO battery demonstrates a notable power density of 2.02 mW cm−2, highlighting a propitious direction for investigating highly efficient conversion of low-concentration NO exhaust gas.

Compared with MX@MoTe2-V, in which the (002) crystal plane of MoTe2 is perpendicular to the MXene layer, MX@MoTe2-P with MoTe2 (002) crystal plane parallel to MXene layer has a more stable interface structure and more sodium ion storage sites, thereby achieving excellent electrochemical performance.

Abstract

The integration of different crystal planes between two-dimensional (2D) materials results in various combinations, which always exert different effects on the electrochemical properties of materials. The metallic 1T′ phase of molybdenum telluride is a promising anode for sodium-ion batteries (SIBs), but its rearrangement and restacking during charge/discharge process causes a decline in cycle. Herein, MX@MoTe2-P with MoTe2 (002) planes parallel to MXene layers and MX@MoTe2-V with MoTe2 (002) planes perpendicular to MXene layers are controllably constructed. Compared with MX@MoTe2-V, the new interface formed between MoTe2 and MXene in MX@MoTe2-P has a stronger van der Waals interaction and larger contact area, helpful to store more sodium ions and contributing to its excellent structural stability and battery capacity. Although MX@MoTe2-V has a higher sodium adsorption energy than MX@MoTe2-P, the small interface area lowers the storage capacity and it further aggravates the collapse of the structure. When used as the anode for SIBs, MX@MoTe2-P offers excellent cycle stability and specific capacity. In particular, sodium-ion full cell consisting of MX@MoTe2-P anode and Na3V2(PO4)3 cathode shows the excellent performance (147.2 mAh g−1@1000 cycles at 5 A g−1) surpassing all the reported MoTe2-based materials. This work provides a guide for the manufacture of new electrode materials.

The authors fabricate a reactive oxygen species-driven oxygenation hydrogel (OxyGel) spray, which can rebalance the oxidative and hypoxic microenvironment of the diabetic wound, promote M1-to-M2 macrophage repolarization, and enhance the survival, migration, and angiogenesis of endothelial cells. A single administration of the OxyGel spray accelerates full-thickness back skin wound and refractory foot ulcer wound healing in diabetic rats.

Abstract

The accumulation of reactive oxygen species (ROS) and poor oxygen supply are two prominent factors of the inflammatory microenvironment that delay diabetic wound healing. However, current clinical treatments cannot achieve effective ROS scavenging and sustained oxygenation. Herein, a ROS-driven oxygenation hydrogel (OxyGel) spray that integrates a multifunctional nanozyme with a dynamically crosslinked sprayable hydrogel matrix is presented. The nanozyme, which is fabricated based on the ceria-zoledronic acid nanoparticles modified with tannic acid (TCZ nanozymes), can mimic the cascade catalytic activities of superoxide dismutase (SOD) and catalase (CAT) to effectively scavenge ROS while generating oxygen. These synergistic actions rebalance the oxidative and hypoxic microenvironment of the diabetic wound, promote M1-to-M2 macrophage repolarization, and enhance the survival, migration, and angiogenesis of endothelial cells. A single administration of the nanozyme via the hydrogel spray stably deposits the nanozymes at the target sites to accelerate full-thickness back skin wound and refractory foot ulcer wound healing in diabetic rats. Furthermore, RNA-seq results revealed the upregulation of multiple signaling pathways related to wound healing by the OxyGel spray, highlighting the potential of this platform not only for the treatment of refractory diabetic wounds but also other diseases associated with oxidative stress and hypoxia.

Magnon torques can overcome the Joule heating issue in traditional spintronic devices. The crystalline dependence of magnon torques in Hf/Cr2O3/FM heterostructures is demonstrated. Magnon torques are generated when the Néel vector of Cr2O3 is parallel to the spin polarization generated in Hf. Furthermore, the magnetization switching of perpendicularly magnetized CoFeB is achieved using magnon torques.

Abstract

Electron motion in spin-orbit torque devices inevitably leads to the Joule heating issue. Magnon torques can potentially circumvent this issue, as it enables the transport of spin angular momentum in insulating magnetic materials. In this work, a sandwich structure composed of Hf/antiferromagnetic Cr2O3/ferromagnet is fabricated and demonstrates that the magnon torque is strongly dependent on the crystalline structure of Cr2O3. Magnon torques are stronger when the Néel vector of Cr2O3 aligns parallel to the spin polarization generated in Hf, while they are suppressed when the Néel vector is perpendicular to the spin polarization. The magnon torque efficiency is estimated to be −0.134 using in-plane second harmonic Hall measurements. Using magnon torques, perpendicular magnetization switching of CoFeB is achieved, with a critical switching current density of 4.09 × 107 A cm−2. Furthermore, the spin angular momentum loss due to the insertion of Cr2O3 is found to be lower than that of polycrystalline NiO. The work highlights the role of antiferromagnet crystalline structures in controlling magnon torques, broadening the potential applications of magnon torques.

A novel magnetoresistance effect termed spin-splitting magnetoresistance (SSMR) is demonstrated in (101)-RuO2/Co bilayers. The SSMR is underpinned by the spin–charge interconversion process induced by the nonrelativistic spin-splitting effect in altermagnets. Utilizing the SSMR, a [001]-oriented Néel vector in an epitaxial thin film of RuO2 is revealed, which evidences its altermagnetism.

Abstract

The recently discovered altermagnets, featured by the exotic correlation of magnetic exchange interaction and alternating crystal environments, have offered exciting cutting-edge opportunities for spintronics. Nevertheless, the altermagnetism of RuO2, one of the earliest-discovered altermagnets, is currently under intense debate. Here, this controversy is attempted to be resolved by demonstrating a spin-splitting magnetoresistance (SSMR) effect that is driven by a spin current associated with the giant nonrelativistic spin splitting of an altermagnet. Compared to the spin Hall magnetoresistance induced by a conventional relativistic spin current, the SSMR is characterized by unusual angular dependence with a phase-shift feature underpinned by the Néel-vector orientation and pronounced temperature dependence caused by its susceptibility to electron scattering. Through systematical investigations on the magnetoresistance of (101)-RuO2/Co bilayers, a sizable SSMR is disentangled and hence a Néel vector along [001] direction is unveiled. This work not only demonstrates a simple electric avenue for probing the Néel vector of altermagnets, but also indicates long-range magnetic order in thin films of RuO2.