Synergistic Cathode Design for High-Performance Dual-Salt Magnesium/Lithium-Ion Batteries Using 2D/2D 1T/2H-MoS2@Ti3C2Tx MXene Nanocomposite.

Magnesium-ion batteries (MIBs) and dual-salt magnesium/lithium-ion batteries (MLIBs) have emerged as promising contenders for next-generation energy storage. In contrast to lithium metal anode in lithium metal batteries, magnesium metal anode in MIBs and MLIBs presents a safer alternative due to the limited dendrite growth and higher volumetric capacity, along with higher natural abundance. This study explores a MLIB configuration with a novel cathode design by employing a 2D/2D nanocomposite of 1T/2H mixed phase MoS2 and delaminated Ti3C2Tx MXene (1T/2H-MoS2@MXene) to address challenges associated with slow kinetics of magnesium ions during cathode interactions. This cathode design takes advantage of the high electrical conductivity of Ti3C2Tx MXene and the expanded interlayer spacing with enhanced conductivity of the 1T metallic phase in 1T/2H mixed phase MoS2. Through a designed synthesis method, the resulting nanocomposite cathode maintains structural integrity, enabling the stable and reversible storage of dual Mg2+ and Li+ ions. The nanocomposite cathode demonstrates superior performance in MLIBs compared to individual components (253 mAh g-1 at 50 mA g-1, and 36% of capacity retention at 1,000 mA g-1), showcasing short ion transport paths and fast ion storage kinetics. This work represents a significant advancement in cathode material design for cost-effective and safe MLIBs.

Electron Configuration Modulation Induced Stabilized 1T-MoS2 for Enhanced Sodium Ion Storage.

1T-MoS2 has become an ideal anode for sodium-ion batteries (SIBs). However, the metastable feature of 1T-MoS2 makes it difficult to directly synthesize under normal conditions. In addition, it easily transforms into 2H phase via restacking, resulting in inferior electrochemical performance. Herein, the electron configuration of Mo 4d orbitals is modulated and the stable 1T-MoS2 is constructed by nickel (Ni) introduction (1T-Ni-MoS2). The original electron configuration of Mo 4d orbitals is changed via the electron injection by Ni, which triggers the phase transition from 2H to 1T phase, thus improving the electrical conductivity and accelerating the redox kinetics of the material. Consequently, 1T-Ni-MoS2 exhibits superior rate capability (266.8 mAh g-1 at 10 A g-1) and excellent cycle life (358.7 mAh g-1 at 1 A g-1 after 350 cycles). In addition, the assembled Na3V2(PO4)3/C||1T-Ni-MoS2 full cells deliver excellent electrochemical properties and show great prospects in energy storage devices.

A sandwich electrochemiluminescence immunoassay based on 1T-MoS2@dual MOFs for detecting CA153.

A "signal-on" electrochemiluminescence (ECL) immunosensor has been proposed for detecting carbohydrate antigen 153 (CA153) based on the dual MOFs sandwich strategy. The conductive and porous substrate consisting of 1T-MoS2 and two-dimensional conductive metal-organic framework (MOF, Ni-HAB) was anchored onto the glassy carbon electrode (GCE) to label the capture antibody (Ab1), and the luminescence-functionalized MOF (Ru(bpy)32+@UiO-66-NH2) was utilized to immobilize the detection second antibody (Ab2) to construct a "signal-on" responsive sandwich-type electrochemiluminescence immunoassay. Meanwhile, tripropylamine (TPA) acts as the co-reactant and provides a luminescence system for Ru(bpy)32+@UiO-66-NH2. The luminescence-functionalized MOFs showed excellent ECL activity owing to the tunable structure of MOFs. The remarkable enhancement in ECL intensity was obtained by the immunoreaction of antigen and antibody. Under the optimized conditions, the biosensor exhibited a detection limit of 0.0001 U mL-1 (S/N = 3) with a wide range from 0.001 to 50 U mL-1. The proposed ECL immunosensor was applicable for detecting human serum samples with a recovery of 99.83 ∼ 101 % (RSD < 5 %). This work demonstrates that the advantage of multifunctional MOFs could be applied to construct highly selective ECL immunosensor, and it may facilitate the diagnosis of breast cancer in clinics.

1T-2H Mixed-Phase MoS2 Stabilized with a Hyperbranched Polyethylene Ionomer for Mg2+ /Li+ Co-Intercalation Toward High-Capacity Dual-Salt Batteries.

Dual-salt magnesium/lithium-ion batteries (MLIBs) benefit from fast lithium ion diffusion on the cathode side while providing safety due to the dendrite-free Mg2+ stripping/plating mechanism on the anode side. Bulk MoS2 (B-MoS2 ), as a cathode for magnesium-ion batteries (MIBs), suffers from low conductivity and relatively van der Waals gaps and, consequently, resists against divalent Mg2+ insertion due to the high Coulombic interactions. In MLIBs, it exhibits a Daniell-cell type mechanism with the sole accommodation of Li+ . In this paper, the synthesis of a 1T/2H mixed-phase MoS2 (MP-MoS2 ) modified with a hyperbranched polyethylene ionomer, I@MP-MoS2 , for high-capacity MLIBs with a distinct Mg2+ /Li+ co-intercalation mechanism is reported. Benefiting from the enhanced conductivity (due to 53% metallic 1T phase), expanded van der Waals gaps (79% expansion compared to B-MoS2 , 1.11 vs 0.62 nm), and enhanced interactions with THF-based electrolytes following the modification, I@MP-MoS2 shows a dramatically increased Mg2+ storage compared to its parent analogue (144 mAh g-1 vs ≈2 mAh g-1 at 20 mA g-1 ). In MLIBs, I@MP-MoS2 is demonstrated to exhibit remarkable specific capacities up to ≈270 mAh g-1 at 20 mA g-1 through a Mg2+ /Li+ co-intercalation mechanism with 87% of capacity retention over 200 cycles at 100 mA g-1 .

Regulatable Phase Manipulation-Enhanced Polarization and Conductance Loss Enabling Hierarchical 3D Microsphere-like MoS2 with Efficient Microwave Absorption.

Molybdenum disulfide (MoS2) has become a new type of microwave absorption (MA) material due to the abundant functional groups and defects, high polarization effect, and controllable structural design. However, the development of MoS2 has been limited by its inherently low conductance losses and imperfect impedance matching. This study employs ammonium ion (NH4+) intercalation as a phase manipulation strategy to enhance dielectric loss and form heterogeneous structures by incorporating highly conductive 1T phase into the 2H-MoS2 crystal phase. Additionally, the implementation of CTAB as a soft template agent for constructing layered three-dimensional microsphere structures improves impedance matching. The experimental findings demonstrate that the MA performance of MoS2 can be effectively regulated by controlling the 1T phase content and morphological structure design. It is worth noting that A-MoS2-2 possesses excellent multifrequency absorption capability. A-MoS2-2 has a minimum reflection loss (RL) of -53 dB at a coating thickness of 1.99 mm and an effective absorption bandwidth (EAB) of 5.6 GHz at a thinner coating thickness of 1.77 mm. This work improves the MA properties of MoS2 by introducing metallic phases and unique structural design, which opens up new ideas for the development of MA materials.

Construction of electrochemical biosensors based on MoSe2@1T-MoS2 heterojunction for the sensitive and rapid detection of miRNA-155 biomarker in breast cancer.

MiRNA-155 is a typical biomarker for breast cancer. Since its low concentration in the physiological environment and the limitations of conventional miRNA detection methods like Northern imprinting and RT-qPCR, convenient, real-time, and rapid detection methods are urgently needed. In this work, an electrochemical biosensor was constructed based on the flower-like MoSe2@1T-MoS2 heterojunction electrode material and specific RNA recognition probes, which can realize the rapid determination of miRNA-155 content with a wide detection range from 1 fM to 1 nM and a limit of detection (LOD) as low as 0.34 fM. Furthermore, the contents of miRNA-155 in blood samples of tumor-bearing mice and normal mice were measured as 724.93 pM and 21.42 pM, respectively by this biosensor, demonstrating its strong identification ability and miRNA-155 can be regarded as an ideal diagnostic marker. On this basis, a portable sensor platform was designed for on-site detection simulation and showed good recovery efficiency from 95.80% to 98.69%. Meanwhile, compared with the standard detection method RT-qPCR, the accuracy and reliability of the biosensor were verified, indicating that the biosensor has the potential to provide point-of-care testing (POCT) for the early diagnosis of breast cancer.

Dynamic phase evolution of MoS3 accompanied by organodiselenide mediation enables enhanced performance rechargeable lithium battery.

Considerable efforts have been devoted to Li-S batteries, typically the soluble polysulfides shuttling effect. As a typical transition metal sulfide, MoS2 is a magic bullet for addressing the issues of Li-S batteries, drawing increasing attention. In this study, we introduce amorphous MoS3 as analogous sulfur cathode material and elucidate the dynamic phase evolution in the electrochemical reaction. The metallic 1T phase incorporated 2H phase MoS2 with sulfur vacancies (SVs-1T/2H-MoS2) decomposed from amorphous MoS3 achieves refined mixing with the "newborn" sulfur at the molecular level and supplies continuous conduction pathways and controllable physical confinement. Meanwhile, the in situ-generated SVs-1T/2H-MoS2 allows lithium intercalation in advance at high discharge voltage (≥1.8 V) and enables fast electron transfer. Moreover, aiming at the unbonded sulfur, diphenyl diselenide (PDSe), as a model redox mediator is applied, which can covalently bond sulfur atoms to form conversion-type organoselenosulfides, changing the original redox pathway of "newborn" sulfur in MoS3, and suppressing the polysulfides shuttling effect. It also significantly lowers the activation energy and thus accelerates the sulfur reduction kinetics. Thus, the in situ-formed intercalation-conversion hybrid electrode of SVs-1T/2H-MoS2 and organoselenosulfides realizes enhanced rate capability and superior cycling stability. This work provides a novel concept for designing high-energy-density electrode materials.

One-step chemically vapor deposited hybrid 1T-MoS2/2H-MoS2 heterostructures towards methylene blue photodegradation.

The photocatalytic degradation of methylene blue is a straightforward and cost-effective solution for water decontamination. Although many materials have been reported so far for this purpose, the proposed solutions inflicted high fabrication costs and low efficiencies. Here, we report on the synthesis of tetragonal (1T) and hexagonal (2H) mixed molybdenum disulfide (MoS2) heterostructures for an improved photocatalytic degradation efficiency by means of a single-step chemical vapor deposition (CVD) technique. We demonstrate that the 1T-MoS2/2H-MoS2 heterostructures exhibited a narrow bandgap âˆ¼ 1.7 eV, and a very low reflectance (<5%) under visible-light, owing to their particular vertical micro-flower-like structure. We exfoliated the CVD-synthesised 1T-MoS2/2H-MoS2 films to assess their photodegradation properties towards the standard methylene blue dye. Our results showed that the photo-degradation rate-constant of the 1T-MoS2/2H-MoS2 heterostructures is much greater under UV excitation (i.e., 12.5 × 10-3 min-1) than under visible light illumination (i.e., 9.2 × 10-3 min-1). Our findings suggested that the intermixing of the conductive 1T-MoS2 with the semi-conducting 2H-MoS2 phases favors the photogeneration of electron-hole pairs. More importantly, it promotes a higher efficient charge transfer, which accelerates the methylene blue photodegradation process.

Bi-Functional Co/Al Modified 1T-MoS2 /rGO Catalyst for Enhanced Uranium Extraction and Hydrogen Evolution Reaction in Seawater.

Uranium is a key element in the preparation of nuclear fuel. An electrochemical uranium extraction technique is proposed to achieve high efficiency uranium extraction performance through HER catalyst. However, it is still a challenge to design and develop a high-performance hydrogen evolution reaction (HER) catalyst for rapid extraction and recovery of uranium from seawater. Herein, a bi-functional Co, Al modified 1T-MoS2 /reduced graphene oxide (CA-1T-MoS2 /rGO) catalyst, showing a good HER performance with a HER overpotential of 466 mV at 10 mA cm-2 in simulated seawater, is first developed. Benefiting from the high HER performance of CA-1T-MoS2 /rGO, efficient uranium extraction is achieved with a uranium extraction capacity of 1990 mg g-1 in simulated seawater without post-treatment, exhibiting a good reusability. The results of experiments and density functional theory (DFT) show that a high uranium extraction and recovery capability is attributed to the synergy effect of the improved HER performance and the strong adsorption capacity between U and OH*. This work provides a new strategy for the design and preparation of bi-functional catalysts with high HER performance and uranium extraction and recovery capabilities in seawater.

The Ability of CO2 Capture on Transition Metal-modified 1T'-MoS2 Monolayers Controlled by an Electric Field.

Herein, we evaluate the CO2 capture ability on the transition metal-modified 1T'-MoS2 monolayers (TM@1T'-MoS2 , TM represents a transition metal atom from 3d to 4d except Y, Tc and Cd) under different external electric fields via first-principles calculations. As the screened results revealed that Mo@1T'-MoS2 , Cu@1T'-MoS2 and Sc@1T'-MoS2 monolayers possess higher sensitivity for electric field than pristine 1T'-MoS2 monolayer. Among the above candidates, Mo@1T'-MoS2 and Cu@1T'-MoS2 monolayers only require the electric field strength of 0.002 a.u. to reversibly capture CO2 and can absorb up to four CO2 molecules with the electric field of 0.004 a.u. Furthermore, Mo@1T'-MoS2 can selectively capture CO2 molecule from the mixture of CH4 and CO2 . Our findings not only provide useful insights that the synergistic effect of electric field and transition metal doping is beneficial for CO2 capture and separation, but also guide the application of 1T'-MoS2 in the field of gas capture.

Graphene dispersant-assisted in situ growth of Re-doped MoS2 nanosheets on carbon cloth and their performance for hydrogen evolution reaction.

Uniform distribution of electrochemically active transition metal compounds on carbon cloth can effective improve their hydrogen evolution reaction (HER) performance, however, harsh chemical treatment of carbon substrates is always unavoidable during this process. Herein, a hydrogen protonated polyamino perylene bisimide (HAPBI) was used as interface active agent for the in situ growth of rhenium (Re) doped MoS2 nanosheets on carbon cloth (Re-MoS2/CC). HAPBI contains a large conjugated core and multiple cationic groups and has been shown to be an effective graphene dispersant. It endowed the carbon cloth excellent hydrophilicity through simple noncovalent functionalization and, meanwhile, provided sufficient active sites to anchor MoO42- and ReO4- via electrostatic interaction. Uniform and stable Re-MoS2/CC composites were facilely obtained by immersing carbon cloth in HAPBI solution followed by hydrothermal treatment in the precursor solution. The doping of Re induced the formation of 1 T phase MoS2, which reached about 40% in the mixture with 2H phase MoS2. Electrochemical measurements showed an overpotential of 183 mV at a current density of 10 mA cm-2 in 0.5 mol L-1 H2SO4 when the molar ratio of Re to Mo is 1:100. This strategy can be further extended to construct other electrocatalysts that using graphene, carbon nanotubes, etc. as conductive additives.

Interfacial Coordination Bonding-Assisted Redox Mechanism-Driven Highly Selective Precious Metal Recovery on Covalent-Functionalized Ultrathin 1T-MoS2.

Rational design of functional material interfaces with well-defined physico-chemical-driven forces is crucial for achieving highly efficient interfacial chemical reaction dynamics for resource recovery. Herein, via an interfacial structure engineering strategy, precious metal (PM) coordination-active pyridine groups have been successfully covalently integrated into ultrathin 1T-MoS2 (Py-MoS2). The constructed Py-MoS2 shows highly selective interfacial coordination bonding-assisted redox (ICBAR) functionality toward PM recycling. Py-MoS2 shows state-of-the-art high recovery selectivity toward Au3+ and Pd4+ within 13 metal cation mixture solutions. The related recycling capacity reaches up to 3343.00 and 2330.74 mg/g for Au3+ and Pd4+, respectively. More importantly, above 90% recovery efficiencies have been achieved in representative PMs containing electronic solid waste leachate, such as computer processing units (CPU) and spent catalysts. The ICBAR mechanism developed here paves the way for interface engineering of the well-documented functional materials toward highly efficient PM recovery.

1T-MoS2 Enriched Hierarchical MoS2 /MoO3 Produced by Phase Transformation for Efficient Hydrogen Evolution Reaction.

In recent years, transition metal sulfides have been widely studied in the context of their use as electrocatalysts. The electrocatalytic propensity of the classical semiconductor MoS2 , which exists in the 1T and 2H phase structures, has attracted extensive attention. Therefore, the synthesis of highly active and stable MoS2 -based catalysts has become the goal of many research efforts. We recently developed a method that can be utilized to prepare the MoS2 /MoO3 heterojunction in a phase-controlled manner. 1T-MoS2 phase enriched MoS2 /MoO3 heterojunction can be generated using a simple hydrothermal and acid treatment sequence and that the heterojunction has a unique three-dimensional structure, large active surface area, and therefore achieve a low overpotential and high catalytic current density, as well as long-term stability for the hydrogen evolution reaction.

Rational construction of Co-promoted 1T-MoS2 nanoflowers towards high-efficiency 4-nitrophenol reduction.

Developing efficient and cost-effective non-noble metal catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) is of great importance. Herein, Co-promoted 1T-MoS2 nanoflowers were synthesized via a one-step hydrothermal method. The influence of Co content on the structure and catalytic performance of 1T-MoS2 was studied in detail. It was found that Co doping not only enhanced the electronic conductivity but also increased the hydrogen adsorption ability of 1T-MoS2. Meanwhile, the highest activity was achieved due to the synergy effect of Co-Mo-S and CoS2 active phase. In the catalytic reduction of 4-NP, the reaction rate constant of Co/1T-MoS2-0.3 was as high as 0.908 min-1 and the catalyst exhibited excellent stability after recycling five times. The present work provides new insights for the rational design of highly efficient metal-doped MoS2 catalysts towards 4-NP reduction in wastewater.

Self-supporting 1T-MoS2@WS2@CC composite materials for potential high-capacity sodium storage system.

Pure phase MoS2 has low conductivity, but with high theoretical specific capacity, and WS2 possesses a high intrinsic conductivity, but suffer from rapid capacity fading. Predictably, the combination of these two transition metal sulfide compounds can complement each other and improve electrochemical performance comprehensively. Whereas, bimetallic phase sulfide of MoS2 and WS2 composites have not been researched in SIBs. In this paper, 1T metallic phase MoS2 and WS2 vertically growth on flexible carbon cloth (CC) surface (1T-MoS2@WS2@CC) by a simple hydrothermal method. The electrochemical performance was improved by heterojunction synergistic effect and the enhanced interlayers of the composite material. Specifically, the superelevation reversible capacity of 529.4 mAh/g can be obtained even after 100 cycles at the current density of 100 mA g-1, and the 259.2 mAh/g capacity can be maintained even at high current density of 1000 mA g-1 after 60 cycles. Besides, the designed 1T-MoS2@WS2@CC composite material has excellent rate performance and cycle stability which are guarantee for battery core performance. Thus, there is every reason to believe that the advanced 1T-MoS2@WS2@CC electrode material has great potential in the future high performance energy storage devices.

A Metal-Organic Frameworks Derived 1T-MoS2 with Expanded Layer Spacing for Enhanced Electrocatalytic Hydrogen Evolution.

Metal phase molybdenum disulfide (1T-MoS2 ) is considered a promising electrocatalyst for hydrogen evolution reaction (HER) due to its activated basal and superior electrical conductivity. Here, a one-step solvothermal route is developed to prepare 1T-MoS2 with expanded layer spacing through the derivatization of a Mo-based organic framework (Mo-MOFs). Benefiting from N,N-dimethylformamide oxide as external stress, the interplanar spacing of (002) of the MoS2 catalyst is extended to 10.87 Å, which represents the largest one for the 1T-MoS2 catalyst prepared by the bottom-up approach. Theoretical calculations reveal that the expanded crystal planes alter the electronic structure of 1T-MoS2 , lower the adsorption-desorption potentials of protons, and thus, trigger efficient catalytic activity for HER. The optimal 1T-MoS2 catalyst exhibits an overpotential of 98 mV at 10 mA cm-2 for HER, corresponding to a Tafel slope of 52 mV dec-1 . This Mo-MOFs-derived strategy provides a potential way to design high-performance catalysts by adjusting the layer spacing of 2D materials.

DFT Simulation-Based Design of 1T-MoS2 Cathode Hosts for Li-S Batteries and Experimental Evaluation.

The main challenge in lithium sulphur (Li-S) batteries is the shuttling of lithium polysulphides (LiPSs) caused by the rapid LiPSs migration to the anode and the slow reaction kinetics in the chain of LiPSs conversion. In this study, we explore 1T-MoS2 as a cathode host for Li-S batteries by examining the affinity of 1T-MoS2 substrates (pristine 1T-MoS2, defected 1T-MoS2 with one and two S vacancies) toward LiPSs and their electrocatalytic effects. Density functional theory (DFT) simulations are used to determine the adsorption energy of LiPSs to these substrates, the Gibbs free energy profiles for the reaction chain, and the preferred pathways and activation energies for the slow reaction stage from Li2S4 to Li2S. The obtained information highlights the potential benefit of a combination of 1T-MoS2 regions, without or with one and two sulphur vacancies, for an improved Li-S battery performance. The recommendation is implemented in a Li-S battery with areas of pristine 1T-MoS2 and some proportion of one and two S vacancies, exhibiting a capacity of 1190 mAh/g at 0.1C, with 97% capacity retention after 60 cycles in a schedule of different C-rates from 0.1C to 2C and back to 0.1C.

Recent progress of electrochemical hydrogen evolution over 1T-MoS2 catalysts.

Developing efficient and stable non-noble metal catalysts for the electrocatalytic hydrogen evolution reaction (HER) is of great significance. MoS2 has become a promising alternative to replace Pt-based electrocatalysts due to its unique layered structure and adjustable electronic property. However, most of the reported 2H-MoS2 materials are stable, but the catalytic activity is not very ideal. Therefore, a series of strategies such as phase modulation, element doping, defect engineering, and composite modification have been developed to improve the catalytic performance of MoS2 in the HER. Among them, phase engineering of 2H-MoS2 to 1T-MoS2 is considered to be the most effective strategy for regulating electronic properties and increasing active sites. Hence, in this mini-review, the common phase modulation strategies, characterization methods, and application of 1T-MoS2 in the HER were systematically summarized. In addition, some challenges and future directions are also proposed for the design of efficient and stable 1T-MoS2 HER catalysts. We hope this mini-review will be helpful to researchers currently working in or about to enter the field.

Facile Synthesis of ZnS/1T-2H MoS2nanocomposite for Boosted adsorption/photocatalytic degradation of methylene blue under visiblelight.

Facile solvothermal techniques were used to manufacture ZnS/1T-2H MoS2 nanocomposite (ZMS) with outstanding adsorption-photocatalytic activity. The formed catalyst was characterized by different tools; XRD, HR-TEM, EDX, FTIR, Raman, N2adsorprion/desorption, Zeta potential, PL,and XPS. The analysis provided the formation on mixed phase of metallic 1Tand 2H phases. ZMS has a high porosity and large specific surface area, and it has a high synergistic adsorption-photocatalytic degradation effect for MB, with a removal efficiency of ≈100% in 45 minutes under visible light irradiation. The extraordinary MB removal efficiency of ZMS was attributed not only to the high specific surface area (49.15 m2/g) and precious reactive sites generated by ZMS, but also to the formation of 1T and 2H phases if compared to pristine MoS2 (MS). The best adsorption affinity was induced by the existance of 1T phase. The remarkably enhanced photocatalytic activity of ZMS nanocomposite can be ascribed to the 2D heterostructure which enhances the adsorption for pollutants, provides abundant reaction active sites, extends the photoresponse to visible light region.

Direct Synthesis of Stable 1T-MoS2 Doped with Ni Single Atoms for Water Splitting in Alkaline Media.

Metallic MoS2 (i.e., 1T-MoS2 ) is considered as the most promising precious-metal-free electrocatalyst with outstanding hydrogen evolution reaction (HER) performance in acidic media comparable to Pt. However, sluggish kinematics of HER in alkaline media and its inability for the oxygen evolution reaction (OER), hamper its development as bifunctional catalysts. The instability of 1T-MoS2 further impedes its applications for scaling up, calling an urgent need for simple synthesis to produce stable 1T-MoS2 . In this work, the challenge of 1T-MoS2 synthesis is first addressed using a direct one-step hydrothermal method by adopting ascorbic acid. 1T-MoS2 with flower-like morphology is obtained, and transition metals (Ni, Co, Fe) are simultaneously doped into 1T-MoS2 . Ni-1T-MoS2 achieves an enhanced bifunctional catalytic activity for both HER and OER in alkaline media, where the key role of Ni doping as single atom is proved to be essential for boosting HER/OER activity. Finally, a Ni-1T-MoS2 ||Ni-1T-MoS2 electrolyzer is fabricated, reaching a current density of 10 mA cm-2 at an applied cell voltage of only 1.54 V for overall water splitting.