Al2 O3 Research Articles

Solid/Solid Interfacial Architecturing of Solid Polymer Electrolyte-Based All-Solid-State Lithium-Sulfur Batteries by Atomic Layer Deposition.

Solid polymer electrolytes (SPEs)-based all-solid-state lithium-sulfur batteries (ASSLSBs) have attracted extensive research attention due to their high energy density and safe operation, which provide potential solutions to the increasing need for harnessing higher energy densities. There is little progress made, however, in the development of ASSLSBs to improve simultaneously energy density and long-term cycling life, mostly due to the "shuttle effect" of lithium polysulfide intermediates in the SPEs and the low interfacial compatibility between the metal lithium anode and the SPE. In this work, the issues of solid/solid interfacial architecturing through atomic layer deposition of Al2 O3 on poly(ethylene oxide)-lithium bis(trifluoromethanesulfonyl)imide SPE surface are effectively addressed. The Al2 O3 coating promotes the suppression of lithium dendrite formation for over 500 h. ASSLSBs fabricated with two layers of Al2 O3 -coated SPE deliver high gravimetric/areal capacity and Coulombic efficiency, as well as excellent cycling stability and extremely low self-discharge rate. This work provides not only a simple and effective approach to boost the electrochemical performances of SPE-based ASSLSBs, but also enriches the fundamental understanding regarding the underlying mechanism responsible for their performance.

Bidirectional energy filtering for electronic and phonon transport in Al2O3/ZnO superlattice films with anisotropy

Directional anisotropy transport in particular in nanostructured superlattice films could be crucial to understanding their thermoelectric properties, including figure-of-merit (ZT). However, few experimental studies have considered anisotropic properties in superlattice films. Therefore, this study investigated electronic and phonon transport anisotropy for atomic layer deposition Al2O3 (AO)/ZnO superlattice films on SiO2/Si substrates at 77–500 K using the four-point-probe 3-ω method and in-house Seebeck measurement system as a first step toward understanding corresponding superlattice film properties. In-plane and out-of-plane ZT values for AO/ZnO superlattice films were determined as 0.00017–0.19 and 0.00035–0.44, respectively, at 77–500 K. Higher ZT for both directions can be explained by synergistic combination of enhanced phonon scattering and bidirectional energy filtering in phonon and electronic transport compared to undoped ZnO films over the temperature range. We also found that out-of-plane thermal conductivity suppression was mostly attributable to increased ZT anisotropy in the out-of-plane direction rather than enhanced AO/ZnO superlattice film Seebeck and power factors.

Interfacial Enhancement by γ-Al2 O3 of Electrochemical Oxidative Dehydrogenation of Ethane to Ethylene in Solid Oxide Electrolysis Cells.

Oxidative dehydrogenation of ethane (ODE) is limited by the facile deep oxidation and potential safety hazards. Now, electrochemical ODE reaction is incorporated into the anode of a solid oxide electrolysis cell, utilizing the oxygen species generated at anode to catalytically convert ethane. By infiltrating γ-Al2 O3 onto the surface of La0.6 Sr0.4 Co0.2 Fe0.8 O3-δ -Sm0.2 Ce0.8 O2-δ (LSCF-SDC) anode, the ethylene selectivity reaches as high as 92.5 %, while the highest ethane conversion is up to 29.1 % at 600 °C with optimized current and ethane flow rate. Density functional theory calculations and in situ X-ray photoelectron spectroscopy characterizations reveal that the Al2 O3 /LSCF interfaces effectively reduce the amount of adsorbed oxygen species, leading to improved ethylene selectivity and stability, and that the formation of Al-O-Fe alters the electronic structure of interfacial Fe center with increased density of state around Fermi level and downshift of the empty band, which enhances ethane adsorption and conversion.

Ultrasensitive NOX Detection in Simulated Exhaled Air: Enhanced Sensing via Alumina Modification of In‐Situ Grown WO3 Nanoblocks

Seedless growth of vertically aligned nanostructures, which can induce smoother transport and minimize Ohmic contact between substrate and semiconductor, can be fabricated by in situ growth utilizing modified hydrothermal methods. Such devices can be useful in designing non-invasive ultrasensitive hand-held sensors for diagnostic identification of volatile organic compounds (VOCs) in exhaled air, offering pain-free and easier detection of long-term diseases such as asthma. In the present work, WO3 nanoblocks, with a high surface area and porosity, have been grown directly over transparent conducting oxide to minimize Ohmic resistance, facilitating smoother electron transfer and enhanced current response. Further modification with porous alumina (γ-Al2 O3 ), by electrodeposition, resulted in the selective and ultrasensitive detection of NOX in simulated exhaled air. Crystal phase purity of as-fabricated pristine as well modified samples is validated with X-ray diffraction analysis. Morphological and microstructural analyses reveal the successful deposition of porous alumina over the surface of WO3 . Improved surface area and porosity is presented by porous alumina in the modified WO3 device, suggesting more active sites for the gas molecules to get adsorbed and diffuse through the pores. Oxygen vacancies, which are detrimental in the transport phenomenon in the presented sensors, have been studied using X-ray photoelectron spectroscopic (XPS) analysis. Gas sensing studies have been performed by fabricating chemiresistor devices based on bare WO3 and Al2 O3 -modified WO3 . The higher sensitivity for NOX gas in case of γ-Al2 O3 -modified WO3 based devices, as compared to bare WO3 -based devices, is attributed to the better surface area and charge transport kinetics. The presented device strategy offers crucial understanding in the design and development of non-invasive, hand-held devices for NO gas present in the human breath, with potential application in medical diagnostics.

CO2 Hydrogenation on Cu/Al2 O3 : Role of the Metal/Support Interface in Driving Activity and Selectivity of a Bifunctional Catalyst.

Selective hydrogenation of CO2 into methanol is a key sustainable technology, where Cu/Al2 O3 prepared by surface organometallic chemistry displays high activity towards CO2 hydrogenation compared to Cu/SiO2 , yielding CH3 OH, dimethyl ether (DME), and CO. CH3 OH formation rate increases due to the metal-oxide interface and involves formate intermediates according to advanced spectroscopy and DFT calculations. Al2 O3 promotes the subsequent conversion of CH3 OH to DME, showing bifunctional catalysis, but also increases the rate of CO formation. The latter takes place 1) directly by activation of CO2 at the metal-oxide interface, and 2) indirectly by the conversion of formate surface species and CH3 OH to methyl formate, which is further decomposed into CH3 OH and CO. This study shows how Al2 O3 , a Lewis acidic and non-reducible support, can promote CO2 hydrogenation by enabling multiple competitive reaction pathways on the oxide and metal-oxide interface.

Toxicological Evaluation and Quantification of Ingested Metal-Core Nanoplastic by Daphnia magna Through Fluorescence and Inductively Coupled Plasma-Mass Spectrometric Methods.

There are few studies on nanoplastic that propose quantification of the amount ingested combined with evaluation of the toxic effects on aquatic organisms. We propose 2 methods to quantify the amount of polystyrene nanoplastic (PSNP) ingested by Daphnia magna: fluorescence intensity, where a fluorescent monomer (F) is added to the PSNP and quantified through fluorescence light microscopy, and total aluminum quantification, where PSNP is synthesized with Al2 O3 metal-core nanoparticles and used for quantification of the nanoplastic ingested by the organism Daphnia magna using inductively coupled plasma-mass spectrometry. In addition, the PSNP was functionalized with palmitic acid to simulate the environmental conditions leading to biological and chemical transformations. Acute and chronic toxicity tests were performed with fluorescent PSNP (PSNP/F) and palmitic acid-functionalized PSNP/F (PSNP/F-PA). The ingestion quantified was higher by factors of 2.8 and 3.0 for PSNP/F-PA and 1.9 and 1.7 for PSNP/F applying the fluorescence intensity and total Al quantifying methods, respectively, when compared to PSNP. These results are consistent with the data obtained in the toxicity tests, which showed an approximately 3 times increase in the adverse effect of PSNP/F-PA on the mobility and reproduction of the organisms. Thus, the strong inhibition of D. magna reproduction caused by PSNP/F-PA in the chronic toxicity tests could be associated with a greater amount of this nanoplastic being ingested by the organisms. Environ Toxicol Chem 2019;38:2101-2110. © 2019 SETAC.

Electronic Communication in Confined Space Coronas of Shell-by-Shell Structured Al2 O3 Nanoparticle Hybrids Containing Two Layers of Functional Organic Ligands.

A first series of examples for confined space interactions of electron-rich and electron-poor molecules organized in an internal corona of shell-by-shell (SbS)-structured Al2 O3 nanoparticle (NP) hybrids is reported. The assembly concept of the corresponding hierarchical architectures relies on both covalent grafting of phosphonic acids on the NPs surface (SAMs formation; SAM=self-assembled monolayer) and exohedral interdigitation of orthogonal amphiphiles as the second ligand layer driven by solvophobic interactions. The electronic communication between the chromophores of different electron demand, such as pyrenes, perylenediimides (PDIs; with and without pyridinium bromide headgroups) and fullerenes was promoted at the layer interface. In this work, it is demonstrated that the efficient construction principle of the bilayer hybrids assembled around the electronically "innocent" Al2 O3 core is robust enough to achieve control over electronic communication between electron-donors and -acceptors in the interlayer region. The electronic interactions between the electron-accepting and electron-donating moieties approaching each other at the layer interface were monitored by fluorescence measurements.

Pentacoordinated Al3+ -Stabilized Active Pd Structures on Al2 O3 -Coated Palladium Catalysts for Methane Combustion.

Supported Pd catalysts are active in catalyzing the highly exothermic methane combustion reaction but tend to be deactivated owing to local hyperthermal environments. Herein we report an effective approach to stabilize Pd/SiO2 catalysts with porous Al2 O3 overlayers coated by atomic layer deposition (ALD). 27 Al magic angle spinning NMR analysis showed that Al2 O3 overlayers on Pd particles coated by the ALD method are rich in pentacoordinated Al3+ sites capable of strongly interacting with adjacent surface PdOx phases on supported Pd particles. Consequently, Al2 O3 -decorated Pd/SiO2 catalysts exhibit active and stable PdOx and Pd-PdOx structures to efficiently catalyze methane combustion between 200 and 850 °C. These results reveal the unique structural characteristics of Al2 O3 overlayers on metal surfaces coated by the ALD method and provide a practical strategy to explore stable and efficient supported Pd catalysts for methane combustion.

Atomic-Layer Deposition-Assisted Double-Side Interfacial Engineering for High-Performance Flexible and Stable CsPbBr3 Perovskite Photodetectors toward Visible Light Communication Applications.

Self-powered photodetectors (PDs) based on inorganic metal halide perovskites are regarded as promising alternatives for the next generation of photodetectors. However, uncontrollable film growth and sluggish charge extraction at interfaces directly limit the sensitivity and response speed of perovskite-based photodetectors. Herein, by assistance of an atomic layer deposition (ALD) technique, CsPbBr3 perovskite thin films with preferred orientation and enlarged grain size are obtained on predeposited interfacial modification layers. Thanks to improved film quality and double side interfacial engineering, the optimized CsPbBr3 (Al2 O3 /CsPbBr3 /TiO2 , ACT) perovskite PDs exhibit outstanding performance with ultralow dark current of 10-11 A, high detectivity of 1.88 × 1013 Jones and broad linear dynamic range (LDR) of 172.7 dB. Significantly, excellent long-term environmental stability (ambient conditions >100 d) and flexibility stability (>3000 cycles) are also achieved. The remarkable performance is credited to the synergistic effects of high carrier conductivity and collection efficiency, which is assisted by ALD modification layers. Finally, the ACT PDs are successfully integrated into a visible light communication system as a light receiver on transmitting texts, showing a bit rate as high as 100 kbps. These results open the window of high performance all-inorganic halide perovskite photodetectors and extends to rational applications for optical communication.

Photoluminescence imaging of europium (III)-doped γ-Al2 O3 nanofiber structures.

Aluminium oxide (Al2 O3 ) has widely been used for catalysts, insulators, and composite materials for diverse applications. Herein, we demonstrated if γ-Al2 O3 was useful as a luminescence support material for europium (Eu) (III) activator ion. The hydrothermal method and post-thermal treatment at 800°C were employed to synthesize Eu(III)-doped γ-Al2 O3 nanofibre structures. Luminescence characteristics of Eu(III) ions in Al2 O3 matrix were fully understood by taking 2D and 3D-photoluminescence imaging profiles. Various sharp emissions between 580 to 720nm were assigned to the 5 D0 →7 FJ (J=0, 1, 2, 3, 4) transitions of Eu(III) activators. On the basis of X-ray diffraction crystallography, Auger elemental mapping and the asymmetry ratio, Eu(III) ions were found to be well doped into the γ-Al2 O3 matrix at a low (1mol%) doping level. A broad emission at 460nm was substantially increased upon higher (2mol%) Eu(III) doping due to defect creation. The first 3D photoluminescence imaging profiles highlight detailed understanding of emission characteristics of Eu(III) ions in Al oxide-based phosphor materials and their potential applications.

Novel Tunnel-Contact-Controlled IGZO Thin-Film Transistors with High Tolerance to Geometrical Variability.

Thin insulating layers are used to modulate a depletion region at the source of a thin-film transistor. Bottom contact, staggered-electrode indium gallium zinc oxide transistors with a 3 nm Al2 O3 layer between the semiconductor and Ni source/drain contacts, show behaviors typical of source-gated transistors (SGTs): low saturation voltage (VD_SAT ≈ 3 V), change in VD_SAT with a gate voltage of only 0.12 V V-1 , and flat saturated output characteristics (small dependence of drain current on drain voltage). The transistors show high tolerance to geometry: the saturated current changes only 0.15× for 2-50 µm channels and 2× for 9-45 µm source-gate overlaps. A higher than expected (5×) increase in drain current for a 30 K change in temperature, similar to Schottky-contact SGTs, underlines a more complex device operation than previously theorized. Optimization for increasing intrinsic gain and reducing temperature effects is discussed. These devices complete the portfolio of contact-controlled transistors, comprising devices with Schottky contacts, bulk barrier, or heterojunctions, and now, tunneling insulating layers. The findings should also apply to nanowire transistors, leading to new low-power, robust design approaches as large-scale fabrication techniques with sub-nanometer control mature.

Milling Down to Nanometers: A General Process for the Direct Dry Synthesis of Supported Metal Catalysts.

Supported catalysts are among the most important classes of catalysts. They are typically prepared by wet-chemical methods, such as impregnation or co-precipitation. Here we disclose that dry ball milling of macroscopic metal powder in the presence of a support oxide leads in many cases to supported catalysts with particles in the nanometer size range. Various supports, including TiO2 , Al2 O3 , Fe2 O3 , and Co3 O4 , and different metals, such as Au, Pt, Ag, Cu, and Ni, were studied, and for each of the supports and the metals, highly dispersed nanoparticles on supports could be prepared. The supported catalysts were tested in CO oxidation, where they showed activities in the same range as conventionally prepared catalysts. The method thus provides a simple and cost-effective alternative to the conventionally used impregnation methods.

Incorporation of oxygen at column boundaries in (Cr,Al)ON hard coatings

Chromium-based hard coatings deposited using physical vapor deposition are commonly applied protective coatings in several technical applications such as cutting or plastics processing. Particularly enhanced oxidation resistance can be achieved using the oxy-nitride coating system (Cr,Al)ON. Although several studies on (Cr,Al)ON have been conducted, details on the incorporation of oxygen into the coating system are still subject of research. This will be discussed in the present paper through three mechanisms. Considering the (Cr,Al)N with a cubic structure, oxygen can be interstitially stored in the lattice. Here, the nitrogen anions are replaced by the oxygen anions leading to the formation of metal vacancies. In addition to the cubic (Cr,Al)ON, other phases can be formed in the coating, e.g. cubic phases of the type (Cr,Al)2+θO3 with θ ≤ 1 or corundum phase α-(Cr,Al)2O3. In both latter phases, nitrogen can be additionally dissolved in the phases. Moreover, oxygen might segregate preferably at column boundaries. This phenomenon has hardly been explored. Therefore, the column boundaries of a (Cr,Al)ON coating are investigated in this work using transmission electron microscopy. The coating deposition was conducted in an industrial scale coating unit using a hybrid technology consisting of direct current and high power pulse magnetron sputtering. The results suggest that higher oxygen concentrations can be detected at column boundaries. Oxygen-rich column boundaries would contribute to explaining most recently studied phenomena in thin hard chromium-based coatings. Among such phenomena are the column separation manifested by a reduced cohesion between microstructural columns or the grain boundary sliding.

Molecular Beam Epitaxy Scalable Growth of Wafer-Scale Continuous Semiconducting Monolayer MoTe2 on Inert Amorphous Dielectrics.

Monolayer MoTe2 , with the narrowest direct bandgap of ≈1.1 eV among Mo- and W-based transition metal dichalcogenides, has attracted increasing attention as a promising candidate for applications in novel near-infrared electronics and optoelectronics. Realizing 2D lateral growth is an essential prerequisite for uniform thickness and property control over the large scale, while it is not successful yet. Here, layer-by-layer growth of 2 in. wafer-scale continuous monolayer 2H-MoTe2 films on inert SiO2 dielectrics by molecular beam epitaxy is reported. A single-step Mo-flux controlled nucleation and growth process is developed to suppress island growth. Atomically flat 2H-MoTe2 with 100% monolayer coverage is successfully grown on inert 2 in. SiO2 /Si wafer, which exhibits highly uniform in-plane structural continuity and excellent phonon-limited carrier transport behavior. The dynamics-controlled growth recipe is also extended to fabricate continuous monolayer 2H-MoTe2 on atomic-layer-deposited Al2 O3 dielectric. With the breakthrough in growth of wafer-scale continuous 2H-MoTe2 monolayers on device compatible dielectrics, batch fabrication of high-mobility monolayer 2H-MoTe2 field-effect transistors and the three-level integration of vertically stacked monolayer 2H-MoTe2 transistor arrays for 3D circuitry are successfully demonstrated. This work provides novel insights into the scalable synthesis of monolayer 2H-MoTe2 films on universal substrates and paves the way for the ultimate miniaturization of electronics.

Development of abrasive jet polishing by using amino thermosetting plastic abrasive for aluminum alloy

A novel hybrid method, using a medium-hardness amino thermoset plastic (ATP) particles in abrasive jet polishing (AJP), was developed. Based on the theoretical and experimental analysis of the influence of critical operative variables on the trend of the polished surface, wonderful discoveries were obtained. ATP abrasive can not only be used in AJP to polish aluminum alloy and achieve uniform surface finish, but also possess a great advantage over the conventional abrasive jet polishing (AJP) technologies using superhard abrasives (e.g., Al 2O3, SiC), that is, abrasive embedding combined with ploughing-groove defeats can be resolved. This significant observation is especially expected to be useful for improving surface quality and fatigue properties of large and complex aircraft structural components made of aluminum alloys or other aerospace materials including titanium alloys and magnesium alloys.

Controllable P- and N-Type Conversion of MoTe2 via Oxide Interfacial Layer for Logic Circuits.

To realize basic electronic units such as complementary metal-oxide-semiconductor (CMOS) inverters and other logic circuits, the selective and controllable fabrication of p- and n-type transistors with a low Schottky barrier height is highly desirable. Herein, an efficient and nondestructive technique of electron-charge transfer doping by depositing a thin Al2 O3 layer on chemical vapor deposition (CVD)-grown 2H-MoTe2 is utilized to tune the doping from p- to n-type. Moreover, a type-controllable MoTe2 transistor with a low Schottky barrier height is prepared. The selectively converted n-type MoTe2 transistor from the p-channel exhibits a maximum on-state current of 10 µA, with a higher electron mobility of 8.9 cm2 V-1 s-1 at a drain voltage (Vds ) of 1 V with a low Schottky barrier height of 28.4 meV. To validate the aforementioned approach, a prototype homogeneous CMOS inverter is fabricated on a CVD-grown 2H-MoTe2 single crystal. The proposed inverter exhibits a high DC voltage gain of 9.2 with good dynamic behavior up to a modulation frequency of 1 kHz. The proposed approach may have potential for realizing future 2D transition metal dichalcogenide-based efficient and ultrafast electronic units with high-density circuit components under a low-dimensional regime.

Adhesion behavior of conventional and high-translucent zirconia: Effect of surface conditioning methods and aging using an experimental methodology.

Evaluate the adhesive behavior of conventional and high-translucent zirconia after surface conditioning and hydrothermal aging. Conventional (ZrC) and high-translucent zirconia (ZrT) specimens were divided into six groups: without surface treatment (ZrC and ZrT), air-borne particle abrasion with 50-μm Al2 O3 sized particles (ZrC-AO and ZrT-AO), and tribochemical treatment with 30-μm silica modified Al2 O3 sized particles (ZrC-T and ZrT-T). Zirconia specimens were treated using an MDP-containing universal adhesive and bonded to two resins blocks with an adhesive luting cement. Microbar specimens with cross-sectioned areas of 1 mm2 were achieved. Half of the microbars were subjected to hydrothermal aging. Bond strength was evaluated by microtensile bond strength test and statistically evaluated by the Weibull analysis. Roughness of the ZrC-AO and ZrT-AO groups were statistically higher. Bond strength analysis revealed higher bond strength for ZrC-AO and ZrC-T groups compared to ZrT-AO and ZrT-T, respectively. Mixed failure was the most frequent for the mechanically treated groups, while no cohesive failures were obtained. Lower values of bond strength were obtained for the mechanically treated high-translucent zirconia groups when compared to their conventional zirconia counterparts. Mechanical surface treatment significantly improved the bond strength to conventional and high-translucent zirconia. Mechanical surface treatment (air-borne particle abrasion or tribochemical treatment) associated with the use of universal adhesives containing MDP could provide a durable bonding to conventional and high-translucent zirconia.

Solar-Driven Water-Gas Shift Reaction over CuOx /Al2 O3 with 1.1 % of Light-to-Energy Storage.

Hydrogen production from coal gasification provides a cleaning approach to convert coal resource into chemical energy, but the key procedures of coal gasification and thermal catalytic water-gas shift (WGS) reaction in this energy technology still suffer from high energy cost. We herein propose adopting a solar-driven WGS process instead of traditional thermal catalysis, with the aim of greatly decreasing the energy consumption. Under light irradiation, the CuOx /Al2 O3 delivers excellent catalytic activity (122 μmol gcat -1 s-1 of H2 evolution and >95 % of CO conversion) which is even more efficient than noble-metal-based catalysts (Au/Al2 O3 and Pt/Al2 O3 ). Importantly, this solar-driven WGS process costs no electric/thermal power but attains 1.1 % of light-to-energy storage. The attractive performance of the solar-driven WGS reaction over CuOx /Al2 O3 can be attributed to the combined photothermocatalysis and photocatalysis.

Radiation dose measurements in a dental orthopantogram unit using indigenously developed optically stimulated luminescence dosimeters.

Dental orthopantogram (OPG)/cone beam computed tomography (CBCT) scanners are gaining popularity due to their 3D imaging with multiplanar view that provides clinical benefits over conventional dental radiography systems. Dental OPG/CBCT provides optimal visualization of adjacent overlaying anatomical structures that will be superpositioned in any single projection. The characteristics of indigenously developed optically stimulated luminescence dosimeters, namely, aluminium oxide doped with carbon (Al2 O3 :C), lithium magnesium phosphate doped with terbium and boron (LiMgPO4 :Tb,B) and lithium calcium aluminium fluoride doped with europium and yttrium (LiCaAlF6 :Eu,Y) were evaluated for their use in dental dosimetry. The dose-response of these dosimeters was studied at X-ray energies 60kV, 70kV and 81kV. Radiation doses were also measured using Gafchromic film for comparison. Radiation dose was measured at eight different locations of a polymethyl methacrylate (PMMA) head phantom including eyes. The optically stimulated luminescence (OSL) sensitivity of LiMgPO4 :Tb,B is about 1.5 times and LiCaAlF6 :Eu, is about 20 times higher than the sensitivity of Al2 O3 :C. It was found that measured radiation doses by the three optically stimulated luminescence dosimeters (OSLDs) and Gafchromic film in the occipital region (back side) of a PMMA phantom, were consistent but variations in dose at other locations were significantly higher. The three OSLDs used in this study were found to be suitable for radiation dose measurement in dental units.

Effect of Bonding Agent on Metal-Ceramic Bond Strength between Co-Cr Fabricated with Selective Laser Melting and Dental Feldspathic Porcelain.

To investigate the effect of bonding agent on the bonding strength between Co-Cr dental alloy, prepared by selective laser melting (SLM), and feldspathic porcelain. The experiments were conducted according to ISO 9693 and the conventional protocols for the production of metal-ceramic dental restorations. After Al2 O3 air-particle abrasion, metal substrates of Co-Cr dental alloy specimens were bonded, using bonding agent (25 specimens), with dental porcelain positioned in layers (opaque, dentin, enamel). Control specimens (25) were also produced without bonding agent. Bonding strength was measured using 3-point bending tests, and the results were statistically analyzed using the t-test and Weibull statistics. Elemental (by SEM/EDS) and crystallographic analyses (by XRD) were conducted on the bonding agent, along cross sections of alloy-porcelain interfaces, and on fracture surfaces. Cohesive fracture occurred (on the porcelain side). The application of the bonding agent decreased the average bonding strength (from 42.27 ± 5.85 to 36.25± 3.26 MPa, P = 0.00006), attributed to the nonexisting reaction between the TiO2 -rich bonding agent and the Co-Cr alloy, but it increased the Weibull modulus (from 7.84 to 12.16), which reflects the reliability of the bond in the tested metal-ceramic specimens. Although the application of bonding agent slightly decreased the bonding strength, all the measured values of the metal-ceramic specimens produced by the SLM technique, with or without the bonding agent, are markedly higher than the minimum value required by ISO 9693 (25 MPa). Moreover, the use of bonding agent favors the increase of the Weibull modulus.