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SnO is lead oxide structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one SnO sheet oriented in the (0, 0, 1) direction. Sn2+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All Sn–O bond lengths are 2.26 Å. O2- is bonded to four equivalent Sn2+ atoms to form a mixture of edge and corner-sharing OSn4 tetrahedra.
SnO is lead oxide structured and crystallizes in the orthorhombic Pmn2_1 space group. The structure is two-dimensional and consists of one SnO sheet oriented in the (0, 0, 1) direction. Sn2+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are one shorter (2.15 Å) and two longer (2.16 Å) Sn–O bond lengths. O2- is bonded in a trigonal planar geometry to three equivalent Sn2+ atoms.
SnO is Tetraauricupride structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one SnO sheet oriented in the (0, 0, 1) direction. Sn2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Sn–O bond lengths are 2.32 Å. O2- is bonded in a rectangular see-saw-like geometry to four equivalent Sn2+ atoms.
SnO is Tetraauricupride structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one SnO sheet oriented in the (0, 0, 1) direction. Sn2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Sn–O bond lengths are 2.32 Å. O2- is bonded in a rectangular see-saw-like geometry to four equivalent Sn2+ atoms.
SnO crystallizes in the orthorhombic Cmc2_1 space group. The structure is two-dimensional and consists of two SnO sheets oriented in the (0, 0, 1) direction. there are two inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.18–2.43 Å. In the second Sn2+ site, Sn2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.18–2.43 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four Sn2+ atoms to form a mixture of distorted corner and edge-sharing OSn4 tetrahedra. In the second O2- site, O2- is bonded to four Sn2+ atoms to form a mixture of distorted corner and edge-sharing OSn4 tetrahedra.
Direct electrochemical production of dissolved ozone could potentially provide economic wastewater treatment and sanitation or a valuable chemical oxidant. Although Ni-Sb-SnO 2 electrocatalysts have the highest known faradaic efficiencies for electrochemical ozone production, the activity and selectivity are not yet sufficient for commercial implementation. This report finds that co-doping Ni and Gd increases the ozone selectivity by a factor of three over Ni alone. These findings are the first demonstration of an active dopant other than Ni in SnO 2 . Electrochemical and physical characterization show that trends in ozone activity are caused by chemical catalysis, not morphology effects, and that conduction band alignment is not a catalytic descriptor for the system. Selective radical quenching experiments and quantum chemistry calculations of thermodynamic energies suggest that the kinetic barriers to form solution-phase intermediates are important for understanding the role of dopants in electrochemical ozone production.
The study investigates the mitigation of radiation damage on p‐type SnO thin‐film transistors (TFTs) with a fast, room‐temperature annealing process. Atomic layer deposition is utilized to fabricate bottom‐gate TFTs of high‐quality p‐type SnO layers. After 2.8 MeV Au 4+ irradiation at a fluence level of 5.2 × 10 12 ions cm −2 , the output drain current and on/off current ratio ( I on / I off ) decrease by more than one order of magnitude, field‐effect mobility ( μ FE ) reduces more than four times, and subthreshold swing (SS) increases more than four times along with a negative shift in threshold voltage. The observed degradation is attributed to increased surface roughness and defect density, as confirmed by scanning electron microscopy (SEM), high‐resolution micro‐Raman, and transmission electron microscopy (TEM) with geometric phase analysis (GPA). A technique is demonstrated to recover the device performance at room temperature and in less than a minute, using the electron wind force (EWF) obtained from low‐duty‐cycle high‐density pulsed current. At a pulsed current density of 4.0 × 10 5 A cm −2 , approximately four times increase in I on / I off is observed, 41% increase in μ FE , and 20% decrease in the SS of the irradiated TFTs, suggesting effectiveness of the new annealing technique.
Moving toward a future of efficient, accessible, and less carbon-reliant energy devices has been at the forefront of energy research innovations for the past 30 years. Metal-halide perovskite (MHP) thin films have gained significant attention due to their flexibility of device applications and tunable capabilities for improving power conversion efficiency. Serving as a gateway to optimize device performance, consideration must be given to chemical synthesis processing techniques. Therefore, how does common substrate processing techniques influence the behavior of MHP phenomena such as ion migration and strain? Here, we demonstrate how a hybrid approach of chemical bath deposition (CBD) and nanoparticle SnO2 substrate processing significantly improves the performance of (FAPbI3)0.97(MAPbBr3)0.03 by reducing micro-strain in the SnO2 lattice, allowing distribution of K+ from K-Cl treatment of substrates to passivate defects formed at the interface and produce higher current in light and dark environments. X-ray diffraction reveals differences in lattice strain behavior with respect to SnO2 substrate processing methods. Through use of conductive atomic force microscopy (c-AFM), conductivity is measured spatially with MHP morphology, showing higher generation of current in both light and dark conditions for films with hybrid processing. Additionally, time-of-flight secondary ionization mass spectrometry (ToF-SIMS) observed the distribution of K+ at the perovskite/SnO2 interface, indicating K+ passivation of defects to improve the power conversion efficiency (PCE) and device stability. We show how understanding the role of ion distribution at the SnO2 and perovskite interface can help reduce the creating of defects and promote a more efficient MHP device.
Inkjet-printed Ce-doped SnO x ETLs achieved improved photovoltaic performance originating from the increased conductivity, suppressed surface defects, and improved energy level alignment at the ETL/perovskite interface, compared to undoped SnO x ETLs.
Potassium fluoride (KF) incorporation to an SnO 2 nanoparticles (NPs) colloidal dispersion for an electron transport layer of enhanced performance and stability for a perovskite solar cell with improved uniformity of the deposited SnO 2 layer.
The transparent conducting oxide SnO 2 is a wide bandgap semiconductor that is easily n-type doped and widely used in various electronic and optoelectronic applications. Experimental reports of the electron mobility of this material vary widely depending on the growth conditions and doping concentrations. In this work, we calculate the electron mobility of SnO 2 from first principles to examine the temperature and doping concentration dependence and to elucidate the scattering mechanisms that limit transport. We include both electron–phonon scattering and electron-ionized impurity scattering to accurately model scattering in a doped semiconductor. Furthermore, we find a strongly anisotropic mobility that favors transport in the direction parallel to the c-axis. At room temperature and intrinsic carrier concentrations, the low-energy polar-optical phonon modes dominate scattering, while ionized-impurity scattering dominates above 10 18 cm −3 .
The electron density, mobility, bandgap, and band alignment of transparent conducting oxides (TCOs) can be tailored by adjusting composition and stoichiometry, thereby enabling interface engineering for diverse semiconductor applications. For example, solar cell efficiency can change enormously by adjusting TCO properties. At the same time, these TCO properties can shift during the deposition of other layers, anneals, and device operation. An ideal TCO should have tunable but stable electro-optical properties. Here, we deposit SnO 2 , (Mg,Zn)O (MZO), and Ga:(Mg,Zn)O (GMZO) films on glass and measure electro-optical characteristics before and after reducing, inert, oxidizing, and CdCl2 anneals over a range of temperatures. Electron density generally increases in the progression from oxidizing to inert and reducing ambients. SnO 2 is relatively stable compared to MZO but has less flexibility for interface engineering. We investigate GMZO as a similar but more stable alternative to MZO.The addition of Ga to MZO has significant effects on electron density and improves electro-optical stability, which can be advantageous for semiconductor applications. Furthermore, we demonstrate that GMZO can be readily incorporated into solar cells.
A liquid scintillator consisting of linear alkylbenzene as the solvent and 2,5-diphenyloxazole as the fluor was developed for the SNO+ experiment. This mixture was chosen as it is compatible with acrylic and has a competitive light yield to pre-existing liquid scintillators while conferring other advantages including longer attenuation lengths, superior safety characteristics, chemical simplicity, ease of handling, and logistical availability. Its properties have been extensively characterized and are presented here. This liquid scintillator is now used in several neutrino physics experiments in addition to SNO+.
SNO+ Collaboration reports its second spectral analysis of reactor antineutrino oscillation using 286 ton-yr of new data. The measured energies of reactor antineutrino candidates were fitted to obtain the second-most precise determination of the neutrino mass-squared difference Δ𝑚$^{2}_{21}$=(7.96$^{+0.48}_{ −0.42}$) × 10 −5 eV2. Constraining Δ𝑚$^{2}_{21}$ and sin 2 𝜃 12 with measurements from long-baseline reactor antineutrino and solar neutrino experiments yields Δ𝑚$^{2}_{21}$=(7.58$^{+0.18}_{−0.17}$) × 10 −5 eV 2 and sin 2 𝜃 12 = 0.308 ± 0.013. This fit also yields a first measurement of the flux of geoneutrinos in the Western Hemisphere, with 73$^{+47}_{−43}$ TNU at SNO+.
The SNO+ detector operated initially as a water Cherenkov detector. The implementation of a sealed cover gas system midway through water data taking resulted in a significant reduction in the activity of 222 Rn daughters in the detector and allowed the lowest background to the solar electron scattering signal above 5 MeV achieved to date. This paper reports an updated SNO+ water phase 8 B solar neutrino analysis with a total livetime of 282.4 days and an analysis threshold of 3.5 MeV. The 8 B solar neutrino flux is found to be (2.32$^{+0.18}_{-0.17}$(stat)$^{+0.07}_{-0.05}$(syst))×10 6 cm -2 s -1 assuming no neutrino oscillations, or (5.36$^{+0.41}_{-0.39}$(stat)+$^{0.17}_{-0.16}$(syst))×10 6 cm -2 s -1 assuming standard neutrino oscillation parameters, in good agreement with both previous measurements and standard solar model calculations. The electron recoil spectrum is presented above 3.5 MeV.
For a sustainable nuclear waste vitrification process at the Hanford Tank Waste Treatment and Immobilization Plant (WTP), proper selection and consistent supply of glass-forming chemicals (GFCs) are crucial. Establishing rigorous acceptance criteria for the characterization of GFCs will be required to operate the vitrification facility and to mitigate any processing issues or failures. Low-activity wastes (LAW) are blended with GFCs to form slurry melter feeds and vitrified in a melter. To enhance properties of waste glasses, new chemicals are being introduced to the current GFC mixture (Vienna et al. 2016; Muller et al. 2017, 2019). In this study, three new GFCs were evaluated for enhanced LAW glass formulations: chromium oxide (Cr 2 O 3 ), vanadium oxide (V 2 O 5 ), and stannic oxide (SnO 2 ). These three oxide components are included in enhanced waste glass (EWG) formulations and GFCs with the appropriate physical and flow properties are needed. As a starting point, single metal oxide GFCs: Cr 2 O 3 , V 2 O 5 , and SnO 2 were sourced and tested. To characterize these new individual GFCs and mixtures of GFCs, the industrial bulk characterization consultant, Jenike and Johanson, was employed to measure physical and flow properties of individual GFCs and their mixtures. Pacific Northwest National Laboratory (PNNL) also measured several selected physical properties for data evaluation as a quality assurance step. In addition, PNNL measured physical and rheological properties of slurry melter feeds containing those GFCs. Subsequent data analyses and verification were conducted. The purpose of this report is to assess the applicability of these GFCs for LAW vitrification based on their properties. This report will help understand measured data and evaluate new GFCs for use. Moreover, this report may give useful insights to help troubleshoot any GFC and melter feed transport and mixing issues that arise during processing, leading to a successful cleanup mission at WTP.
Photocurrent density in excess of 10 mA cm −2 reported on 2.0 eV CuInGaS 2 solar cells integrated on SnO 2 :F substrates, yet new wide bandgap n-type buffers required to achieve higher photoconversion efficiency.
2D SnO 2 nanosheets based chemiresistive sensor with microporosity and oxygen rich-surface detects ammonia at room temperature in extreme humidity at ppb levels for breath based early disease diagnostics and healthcare.