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Because of their unique structural, chemical, optical, and biological properties, metal phosphate coatings are highly versatile for various applications. Thermodynamically facile and favorable functionalization of phosphate moieties (like orthophosphates, metaphosphates, pyrophosphates, and phosphorus-doped oxides) makes them highly sought-after functional materials as well. Being a sequential self-limiting technique, atomic layer deposition has been used for producing high-quality conformal coatings with sub-nanometer control. In this review, different atomic layer deposition-based strategies used for the deposition of phosphate materials are discussed. The mechanisms underlying those strategies are discussed, highlighting advantages and limitations of specific process chemistries. In a second part, the application of metal phosphates deposited through atomic layer deposition in energy storage and other emerging technologies such as electrocatalysis, biomedical, or luminescence applications are summarized. Next to this, perspectives on untangled knowledge gaps and opportunities for future research are also emphasized. [ABSTRACT FROM AUTHOR]

This work demonstrates the possible usages of indium tin oxide (ITO) thin‐films as multifunctional coatings on V2O5 model electrodes for lithium‐ion batteries (LIBs). The thin films are produced with the atomic layer deposition (ALD) method via adjusting the ratio of In2O3 and SnO2 sub‐layers to a well‐controlled In: Sn contents. The highest conductivity value (7.37 × 10−4 Ω cm) of as‐grown ITO film is obtained from the sample containing 5% SnO2 of overall ALD cycles. The ITO thin‐films are further investigated as multifunctional coatings on ALD V2O5 electrodes for LIBs: At first, dual electronic and ionic conductive protecting properties of ITO layer are explored to attenuate the fading of the battery capacity by improving the cycling stability. Second, the feasibility of ITO layer as a dual functioning current collector‐cum‐protective coating layer is demonstrated. Third, ITO layer is investigated as a current collector and display performance comparable to that of Pt as current collector of traditional thin‐film LIBs. The electronic and electrochemical properties of ITO provide the opportunity to use ITO as a multifunctional coating for (3D) thin‐film LIBs and can find potential usages in miniaturized electronic devices. [ABSTRACT FROM AUTHOR]

Herein, the performance of atomic layer deposited (ALD)‐Nb2O5 is compared with existing standard electron transport layer (ETL) configuration in planar n‐i‐p perovskite solar cell architectures. By making use of a co‐evaporated perovskite absorber layer, electron transport materials, such as phenyl‐C61‐butyric acid methyl ester (PCBM), TiO2, and Nb2O5, are compared in stand‐alone and bilayer configurations. The device performance in terms of hysteresis, scan rate dependency, and stability is associated with ETL–perovskite interactions and ALD‐Nb2O5 fabricated using a PCBM interfacial layer exhibits superior behavior on all fronts. Using an atomic layer deposition technique can drastically reduce the process temperatures, resulting in conformal Nb2O5 suitable for evaporated perovskite absorbers with promise toward using them in flexible applications. [ABSTRACT FROM AUTHOR]

In this paper we present a teleportation protocol by which the multitask of transfer of a two-qubit and two single-qubit quantum states is performed simultaneously with the help of a single entangled channel. The protocol is under the supervision of a controller. There are three pairs of senders and receivers who are connected among themselves along with the controller by a single entangled state. The teleportation protocol is perfect. [ABSTRACT FROM AUTHOR]

Due to its high theoretical capacity, energy density, and excellent reversibility with Li/Li+, molybdenum oxide is one of the vastly studied electrode material in lithium-ion batteries. However, like most of the oxides, it also suffers from poor cyclic stability because of its low electrical conductivity. In 3D core-shell structure prepared by atomic layer deposition coating, it can provide superiority in nanoscale decoration than other deposition methods because of its extreme conformality and precise thickness control on high aspect ratio surfaces. This report illustrates the electrochemical activity of 3D core-shell type amorphous MoO x material coated by atomic layer deposition technique on conducting carbon nanotubes (CNT) scaffold which exhibits excellent overall cell capacity. The obtained capacity is manifold higher than its planar 2D counterpart and that can become an advanced nanoscale fabrication methodology of such 3D nanostructures for electrode preparation. Such binder free MoO x/CNT core-shell electrode structure shows very high and stable electrochemical activity toward Li/Li+ system. An optimal thickness of MoO x on CNT is also found out in order to attain the most stable cyclic performance of this nanostructure. A stable reversible areal capacity of 645 µAh cm−2 with specific capacity of 915 mAh g−1 is achieved from optimized MoO x/CNT assembly. [ABSTRACT FROM AUTHOR]

Mitigating photocorrosion in the light absorber material used for photoelectrochemical solar water splitting is a subject of major research. In this work, a systematic investigation is carried out on suppressing the photocorrosion in an electrodeposited Cu2O photocathode using stable protective layers. The photocathode protected with chemical vapor deposited graphene offers significant stability, till 600 s during light chopping chronoamperometry. However, the presence of a few microcracks in the graphene layer cannot offer complete protection, and causes a gradual decay in the photocurrent. The addition of an ultrathin layer (≈10 nm) of amorphous TiO2 on top of the graphene blocks the microcracks, thereby resulting in complete protection to the Cu2O absorber layer. The TiO2/graphene protected Cu2O photocathode generates -3 mA cm−2 photocurrent at 0.0 V versus reversible hydrogen electrode under 1 sun in 1 m Na2SO4 electrolyte (pH 7), which is twice that compared to the bare Cu2O electrode. The enhancement in photocurrent can be attributed to the ease of separating the photogenerated charge carriers due to the suitable band alignment and electron selective nature of the protective TiO2/graphene layers. [ABSTRACT FROM AUTHOR]

Thin films of cobalt oxide are deposited by atomic layer deposition using dicobalt octacarbonyl [Co2(CO)8] and ozone (O3) at 50°C on microscope glass substrates and polished Si(111) wafers. Self-saturated growth mechanism is verified by x-ray reflectivity measurements. As-deposited films consist of both the crystalline phases; CoO and Co3O4 that gets converted to pure cubic-Co3O4 phase upon annealing at 500 °C under ambient condition. Elemental composition and uniformity of the films is examined by x-ray photoelectron spectroscopy and secondary ion-mass spectroscopy. Both as-deposited and the annealed films have been successfully tested as a catalyst for hydrogen evolution from sodium borohydride hydrolysis. The activation energy of the hydrolysis reaction in the presence of the as-grown catalyst is found to be ca. 38 kJ mol°1. Further implementation of multiwalled carbon nanotube, as a scaffold layer, improves the hydrogen generation rate by providing higher surface area of the deposited catalyst. [ABSTRACT FROM AUTHOR]

Phosphorous-containing materials are used in a wide array of fields, from energy conversion and storage to heterogeneous catalysis and biomaterials. Among these materials, organic-inorganic metal phosphonate solids and thin films present an interesting option, due to their remarkable thermal and chemical stability. Yet, the synthesis of phosphonate hybrids by vapour phase thin film deposition techniques remains largely unexplored. In this work, we present successful deposition of phosphonate-containing films using dimethyl vinylphosphonate (DMVP) as a phosphonate precursor. Two processes have been studied, being a three-step process comprising alternating exposure to trimethylaluminum (TMA), water (H 2 O) and DMVP (ABC process), and a four-step process with an extra O 3 step following the DMVP pulse (ABCD process). The O 3 treatment is employed for in situ functionalisation of the adsorbed phosphonate precursor, transforming the vinyl group into a carboxylic acid end group. For both processes, good precursor saturation was found, with the ABCD process exhibiting a more stable growth per cycle (0.54-0.38 Å per cycle) in the investigated temperature range (100-250 °C). Phosphonate features were visible in FTIR spectra for both films, with the ABCD films also exhibiting a carboxylate signal. XPS showed a higher P incorporation in the ABCD films deposited at 250 °C, although still moderate (P/Al = 0.27), consistent with an alumina structure with phosphonate inclusions. The film stability upon immersion in water was tested, showing a slow oxidation over the course of a week. Finally, annealing experiments in air demonstrated stable films up to 400 °C.