Publications by authors named "Mohamed Hedhili"

The significant contact resistance at the metal-semiconductor interface is a well-documented issue for organic thin-film transistors (OTFTs) that hinders device and circuit performance. Here, this issue is tackled by developing three new thiol carbazole-based self-assembled monolayer (SAM) molecules, namely tBu-2SCz, 2SCz, and Br-2SCz, and utilizing them as carrier-selective injection interlayers. The SAMs alter the work function of gold electrodes by more than 1 eV, making them suitable for use in hole and electron-transporting OTFTs.

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  • A new reducing agent based on hydrosilanes (Si-H) allows for synthesis of high-quality, monodisperse InAs CQDs with tunable excitonic peaks, avoiding harmful compounds that cause surface oxidation.
  • These CQDs exhibit excellent optoelectronic properties, leading to photodetectors with low dark current, good quantum efficiency, and fast photoresponse times, while eliminating a major barrier related to (TMS)As usage
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The electrocatalytic synthesis of ammonia (NH) through the nitrogen reduction reaction (NRR) under ambient temperature and pressure is emerging as an alternative approach to the conventional Haber-Bosch process. However, it remains a significant challenge due to poor kinetics, low nitrogen (N) solubility in aqueous electrolytes, and the competing hydrogen evolution reaction (HER), which can significantly impact NH production rates and Faradaic efficiency (FE). Herein, a rationally designed boron-doped molybdenum sulfide (B-Mo-MoS) electrocatalyst is reported that effectively enhances N reduction to  NH with an onset potential of -0.

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Ultraflat metal foils are essential for semiconductor nanoelectronics applications and nanomaterial epitaxial growth. Numerous efforts have been devoted to metal surface engineering studies in the past decades. However, various challenges persist, including size limitations, polishing non-uniformities, and undesired contaminants.

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  • Shortwave infrared (SWIR) light emitters and detectors are important for various applications but currently depend on expensive semiconductors like InGaAs, which are hard to integrate with existing silicon technology.
  • Colloidal quantum dots (CQDs) represent a cheaper alternative but often contain harmful heavy metals, which limits their use.
  • The study presents a new method to create InAs/ZnSe core/shell quantum dots that improve performance in the SWIR range, with high efficiency and low dark current, successfully demonstrating their use in photodetectors.
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  • - Hexagonal boron nitride (hBN) is a crucial two-dimensional insulator that could revolutionize post-silicon electronics, but there are challenges in producing high-quality monolayers for use in semiconductors.
  • - The research focuses on understanding the chemical vapor deposition (CVD) process for synthesizing hBN, specifically how varying oxygen levels can influence the shape and quality of hBN crystals.
  • - By utilizing density functional theory, the study reveals mechanisms behind hBN growth and highlights methods for creating large-area, high-quality single-crystal films, paving the way for efficient production techniques in industry.
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Diamond-type silicon has a work function of ≈4.8 eV, and conventional n- or p-type doping modifies the value only between 4.6 and 5.

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Separations are core processes in the chemical and pharmaceutical industries. Several steps of fractionation and purification of multicomponent mixtures are required. Membrane technology can operate at fair temperatures, saving energy and processing sensitive compounds.

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We report the engineering and synthesis of peptide nucleic acid-functionalized TiCT MXene nanosheets as a novel transducing material for amplification-free, nanoparticle-free, and isothermal electrochemical detection of microRNA biomarkers. Through bio-orthogonal copper-free click chemistry, azido-modified MXene nanosheets are covalently functionalized with clickable peptide nucleic acid probes targeting prostate cancer biomarker hsa-miR-141. The platform demonstrates a wide dynamic range, single-nucleotide specificity, and 40 aM detection limit outperforming more complex, amplification-based methods.

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Mn-based catalysts are promising candidates for eliminating harmful nitrogen oxides (NO) via selective catalytic reduction with ammonia (NH-SCR) due to their inherent strong redox abilities. However, poor water tolerance and low N selectivity are still the main limitations for practical applications. Herein, we succeeded in preparing an active catalyst for NH-SCR with improved water tolerance and N selectivity based on protecting MnO with a secondary growth of a hydrophobic silicalite-1.

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In advanced batteries, interphases serve as the key component in stabilizing the electrolyte with reactive electrode materials far beyond thermodynamic equilibria. While an active interphase facilitates the transport of working ions, an inactive interphase obstructs ion flow, constituting the primary barrier to the realization of battery chemistries. Here, a successful transformation of a traditionally inactive passivating layer on Mg-metal anode, characteristic of Mg-metal batteries with typical carbonate electrolytes, into an active and robust interphase in the Li-metal scenario is presented.

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Although numerous polymer-based composites exhibit excellent dielectric permittivity, their dielectric performance in various applications is severely hampered by high dielectric loss induced by interfacial space charging and a leakage current. Herein, we demonstrate that embedding molten salt etched MXene into a poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE))/poly(methyl methacrylate) (PMMA) hybrid matrix induces strong interfacial interactions, forming a close-packed inner polymer layer and leading to significantly suppressed dielectric loss and markedly increased dielectric permittivity over a broad frequency range. The intensive molecular interaction caused by the dense electronegative functional terminations (-O and -Cl) in MXene results in restricted polymer chain movement and dense molecular arrangement, which reduce the transportation of the mobile charge carriers.

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Atomically precise copper nanoclusters (NCs) are an emerging class of nanomaterials for catalysis. Their versatile core-shell architecture opens the possibility of tailoring their catalytically active sites. Here, we introduce a core-shell copper nanocluster (CuNC), [Cu(SBu)Cl(PPh)H]BuSO (SBu: -butylthiol; PPh: triphenylphosphine), CuNC, with multiple accessible active sites on its shell.

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Circularly polarized light-emitting diodes (CP-LEDs) are critical for next-generation optical technologies, ranging from holography to quantum information processing. Currently deployed chiral luminescent materials, with their intricate synthesis and processing and limited efficiency, are the main bottleneck for CP-LEDs. Chiral metal nanoclusters (MNCs) are potential CP-LED materials, given their ease of synthesis and processability as well as diverse structures and excited states.

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The efficacy of neural electrode stimulation and recording hinges significantly on the choice of a neural electrode interface material. Transition metal carbides (TMCs), particularly titanium carbide (TiC), have demonstrated exceptional chemical stability and high electrical conductivity. Yet, the fabrication of TiC thin films and their potential application as neural electrode interfaces remains relatively unexplored.

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Article Synopsis
  • Colloidal quantum dots (CQDs) are promising materials for short-wave infrared photodetectors but traditional lead and mercury systems are limited due to toxicity issues.
  • InSb CQDs present an eco-friendly alternative with tunable bandgaps, but their current synthesis methods are complex and hinder their use.
  • A new one-pot synthesis approach using commercial precursors allows for easier production of high-quality InSb CQDs, enabling better performance and efficient carrier dynamics, expanding their application potential in the SWIR range.
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InAs colloidal quantum dots (CQDs) have emerged as candidate lead- and mercury-free solution-processed semiconductors for infrared technology due to their appropriate bulk bandgap, which can be tuned by quantum confinement, and promising charge-carrier transport properties. However, the lack of suitable arsenic precursors and readily accessible synthesis conditions have limited InAs CQDs to smaller sizes (<7 nm), with bandgaps largely restricted to <1400 nm in the near-infrared spectral window. Conventional InAs CQD synthesis requires highly reactive, hazardous arsenic precursors, which are commercially scarce, making the synthesis hard to control and study.

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Superconductivty has recently been induced in MXenes through surface modification. However, the previous reports have mostly been based on powders or cold-pressed pellets, with no known reports on the intrinsic superconsucting properties of MXenes at the nanoale. Here, it is developed a high-temperature atomic exchange process in NH atmosphere which induces superconductivity in either singleflakes or thin films of Nb CT MXene.

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The synthesis of heterogeneous Ti(IV)-based catalysts for ethylene polymerization following surface organometallic chemistry concepts is described. The unique feature of this catalyst arises from the silica support, KCC-1. It has (i) a 3D fibrous morphology that is essential to improve the diffusion of the reactants, and (ii) an aluminum-bound hydroxyl group, [(Si-O-Si)(Si-O-)Al-OH] 2, used as an anchoring site.

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The α-molybdenum trioxide has attracted much attention for proton storage owing to its easily modified bilayer structure, fast proton insertion kinetics, and high theoretical specific capacity. However, the fundamental science of the proton insertion mechanism in α-molybdenum trioxide has not been fully understood. Herein, we uncover a three-proton intercalation mechanism in α-molybdenum trioxide using a specially designed phosphoric acid based liquid crystalline electrolyte.

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Growing continuous monolayer films of transition-metal dichalcogenides (TMDs) without the disruption of grain boundaries is essential to realize the full potential of these materials for future electronics and optoelectronics, but it remains a formidable challenge. It is generally believed that controlling the TMDs orientations on epitaxial substrates stems from matching the atomic registry, symmetry, and penetrable van der Waals forces. Interfacial reconstruction within the exceedingly narrow substrate-epilayer gap has been anticipated.

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MXenes, a fast-growing family of two-dimensional (2D) transition metal carbides/nitrides, are promising for electronics and energy storage applications. Mo CT MXene, in particular, has demonstrated a higher capacity than other MXenes as an anode for Li-ion batteries. Yet, such enhanced capacity is accompanied by slow kinetics and poor cycling stability.

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Gate controllability is a key factor that determines the performance of GaN high electron mobility transistors (HEMTs). However, at the traditional metal-GaN interface, direct chemical interaction between metal and GaN can result in fixed charges and traps, which can significantly deteriorate the gate controllability. In this study, Ti C T MXene films are integrated into GaN HEMTs as the gate contact, wherein van der Waals heterojunctions are formed between MXene films and GaN without direct chemical bonding.

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Solar-blind self-powered UV-C photodetectors suffer from low performance, while heterostructure-based devices require complex fabrication and lack p-type wide band gap semiconductors (WBGSs) operating in the UV-C region (<290 nm). In this work, we mitigate the aforementioned issues by demonstrating a facile fabrication process for a high-responsivity solar-blind self-powered UV-C photodetector based on a p-n WBGS heterojunction structure, operating under ambient conditions. Here, heterojunction structures based on p-type and n-type ultra-wide band gap WBGSs (i.

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The popular metal-ion batteries (MIBs) suffer from environmental and economic issues because of their heavy dependency on nonrenewable metals. Here, we propose a metal-free ammonium (NH )-based dual-ion battery with a record-breaking operation voltage of 2.75 V.

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