Publications by authors named "Marshet Getaye Sendeku"

There is an urgent need to develop a cost-effective and highly efficient acidic OER catalyst to support the progress of proton exchange membrane water electrolysis technology. Ruthenium-based catalysts, which possess high activity and significantly lower cost compared to iridium-based catalysts, emerge as competitive candidates. However, their suboptimal stability constrains the wide application of RuO.

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Steering on the intrinsic active site of an electrode material is essential for efficient electrochemical biomass upgrading to valuable chemicals with high selectivity. Herein, we show that an in-situ surface reconstruction of a two-dimensional layered CdPS nanosheet electrocatalyst, triggered by electrolyte, facilitates efficient 5-hydroxymethylfurfural (HMF) hydrogenation to 2,5-bis(hydroxymethyl)furan (BHMF) under ambient condition. The in-situ Raman spectroscopy and comprehensive post-mortem catalyst characterizations evidence the construction of a surface-bounded CdS layer on CdPS to form CdPS/CdS heterostructure.

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Heterogeneous electrocatalysis closely relies on the electronic structure of the catalytic materials. The ferroelectric-to-paraelectric phase transition of the materials also involves a change in the state of electrons that could impact the electrocatalytic activity, but such correlation remains unexplored. Here, we demonstrate experimentally and theoretically that the intrinsic electrocatalytic activity could be regulated as exampled by hydrogen evolution reaction catalysis over two-dimensional ferroelectric CuInPS.

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Photoelectrochemical (PEC) catalysis provides the most promising avenue for producing value-added chemicals and consumables from renewable precursors. Over the last decades, PEC catalysis, including reduction of renewable feedstock, oxidation of organics, and activation and functionalization of C─C and C─H bonds, are extensively investigated, opening new opportunities for employing the technology in upgrading readily available resources. However, several challenges still remain unsolved, hindering the commercialization of the process.

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Simultaneous electrochemical reduction of nitrite and carbon dioxide (CO ) under mild reaction conditions offers a new sustainable and low-cost approach for urea synthesis. However, the development of urea electrosynthesis thus far still suffers from low selectivity due to the high energy barrier of CO formation and the subsequent C─N coupling. In this work, a highly active dendritic Cu Ni catalyst is developed to enable the highly selective electrosynthesis of urea from co-reduction of nitrite and CO , reaching a urea Faradaic efficiency (FE) and production rate of 39.

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The ultrathin thickness of 2D layered materials affords the control of their properties through defects, surface modification, and electrostatic fields more efficiently compared with bulk architecture. In particular, patterning design, such as moiré superlattice patterns and spatially periodic dielectric structures, are demonstrated to possess the ability to precisely control the local atomic and electronic environment at large scale, thus providing extra degrees of freedom to realize tailored material properties and device functionality. Here, the scalable atomic-scale patterning in superionic cuprous telluride by using the bonding difference at nonequivalent copper sites is reported.

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The direct seawater electrolysis at high current density and low overpotential affords an effective strategy toward clean and renewable hydrogen fuel production. However, the severe corrosion of anode as a result of the saturation of Cl upon continuous seawater feeding seriously hamper the electrolytic process. Herein, cobalt ferricyanide / cobalt phosphide (CoFePBA/Co P) anodes with Cap/Pin structure are synthesized, which stably catalyze alkaline saturated saline water oxidation at 200-2000 mA cm over hundreds of hours without corrosion.

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Iron oxyhydroxide has been considered an auspicious electrocatalyst for the oxygen evolution reaction (OER) in alkaline water electrolysis due to its suitable electronic structure and abundant reserves. However, Fe-based materials seriously suffer from the tradeoff between activity and stability at a high current density above 100 mA cm . In this work, the Ce atom is introduced into the amorphous iron oxyhydroxide (i.

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Electrocatalytic two-electron water oxidation affords a promising approach for distributed production of HO using electricity. However, it suffers from the trade-off between the selectivity and high production rate of HO due to the lack of suitable electrocatalysts. In this study, single atoms of Ru were controllably introduced into titanium dioxide to produce HO through an electrocatalytic two-electron water oxidation reaction.

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The concurrent photocatalytic synthesis of hydrogen gas and high-valued chemicals over two-dimensional semiconductors is extremely attractive to alleviate global energy and environmental concerns through directly using sunlight. Herein, a novel layered InPSe nanosheet is synthesized by a space confined chemical vapor conversion method, and it acts as a dual-functional photocatalyst to deliver the co-production of hydrogen gas and -benzylidenebenzylamine from water reduction and selective benzylamine oxidation. The simultaneous yield of hydrogen gas and -benzylidenebenzylamine is 895 μmol g and 681 μmol g, respectively, within 16-hour continuous reaction involving a small amount of water in acetonitrile solvent.

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Waste plastics are non-degradable constituents that can stay in the environment for centuries. Their large land space consumption is unsafe to humans and animals. Concomitantly, the continuous engineering of plastics, which causes depletion of petroleum, poses another problem since they are petroleum-based materials.

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Intrinsic two-dimensional (2D) magnetic materials own strong long-range magnetism while their characteristics of the ultrathin thickness and smooth surface provide an ideal platform for manipulating the magnetic properties at 2D limit. This makes them to be potential candidates in various spintronic applications compared to their corresponding bulk counterparts. The discovery of magnetic ordering in 2D CrIand GrGeTenanostructures stimulated tremendous research interest in both experimental and theoretical studies on various intrinsic magnets at 2D limit.

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Overcoming the sub-5 nm gate length limit and decreasing the power dissipation are two main objects in the electronics research field. Besides advanced engineering techniques, considering new material systems may be helpful. Here, we demonstrate two-dimensional (2D) subthermionic field-effect transistors (FETs) with sub-5 nm gate lengths based on ferroelectric (FE) van der Waals heterostructures (vdWHs).

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Two-dimensional materials have been widely used in electronics due to their electrical properties that are not accessible in traditional materials. Here, we present the first demonstration of logic functions of unipolar memristors made of functionalized HfSeO flakes and memtransistors made of MoS/graphene/HfSeO van der Waals heterostructures. The two-terminal memristors exhibit stable unipolar switching behavior with high switching ratio (>10), high operating temperature (106 °C), long-term endurance (>10 s), and multibit data storage and can operate as memory latches and logic gates.

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The manipulation of magnetism provides a unique opportunity for the development of data storage and spintronic applications. Until now, electrical control, pressure tuning, stacking structure dependence, and nanoscale engineering have been realized. However, as the dimensions are decreased, the decrease of the ferromagnetism phase transition temperature () is a universal trend in ferromagnets.

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Ferroelectric field-effect transistors (FeFETs) are one of the most interesting ferroelectric devices; however, they, usually suffer from low interface quality. The recently discovered 2D layered ferroelectric materials, combining with the advantages of van der Waals heterostructures (vdWHs), may be promising to fabricate high-quality FeFETs with atomically thin thickness. Here, dual-gated 2D ferroelectric vdWHs are constructed using MoS , hexagonal boron nitride (h-BN), and CuInP S (CIPS), which act as a high-performance nonvolatile memory and programmable rectifier.

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Layered transition metal phosphorous trichalcogenide (MPX) materials have attracted immense attention due to their excellent optical and electrical properties. However, the controllable synthesis of ultrathin MPX nanosheets is still challenging. Here, we present a facile phosphosulfurization scheme to prepare high-quality layered FePS nanosheets, with ∼20 nanometers in thickness.

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Mixed-dimensional van der Waals (vdW) heterostructures based on two-dimensional (2D) materials exhibit immense potential in infrared optoelectronic applications. However, the weak vdW coupling results in limiting performance of infrared optoelectronic device. Here, we exploit a gapless heterostructure that S dangling bonds of nonlayered PbS are connected to the bonding sites of MoS (with factitious S vacancies) strong orbital hybridization.

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Two-dimensional layered materials have been considered as promising candidates for resistive random access memory, one of the most promising next-generation nonvolatile memories. However, due to the types of defects, most of the devices still suffer from poor environmental stability, defects inducing complexity, and uncontrollability. Here, we fabricate memory cells based on synthesized high-quality two-dimensional layered transition-metal oxide (α-MoO) nanosheets which can be thinned to 8.

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α-MnS, as a nonlayered type material with a wide band gap of 2.7 eV, has been expected to supplement the scarcity of two-dimensional (2D) type semiconductors, which are desperately required for constructing atomically thin junctions. However, the preparation and property investigation of 2D α-MnS has scarcely been reported so far.

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In recent years, 2D layered materials have received considerable research interest on account of their substantial material systems and unique physicochemical properties. Among them, 2D layered transition metal dichalcogenides (TMDs), a star family member, have already been explored over the last few years and have exhibited excellent performance in electronics, catalysis, and other related fields. However, to fulfill the requirement for practical application, the batch production of 2D TMDs is essential.

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Van der Waals materials and their heterostructures provide a versatile platform to explore new device architectures and functionalities beyond conventional semiconductors. Of particular interest is anti-ambipolar behavior, which holds potentials for various digital electronic applications. However, most of the previously conducted studies are focused on hetero- or homo- p-n junctions, which suffer from a weak electrical modulation.

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