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This reply provides updated energy consumption estimates at clearly defined separation conditions for electrochemical desalination concepts.

We conduct a techno-economic analysis of electrochemical water deionization technologies. The objective of the analysis is to compare cost, volume, and energy consumption of membrane capacitive deionization (mCDI) to intercalative deionization techniques. Here, we first explore the concept of hybrid capacitive deionization (HCDI), i.e., a cation intercalation electrode paired with an activated carbon capacitive electrode. Then we explore in detail a novel device concept, fully intercalative water deionization (IDI), which relies entirely on the cation intercalation principle. The intercalation host materials in our study are Prussian blue analogs (PBAs), e.g., NiFe(CN)6 or CuFe(CN)6, that offer ∼3–5× higher gravimetric salt removal capacities than typical activated carbon. Our analysis shows that IDI should be superior to mCDI in module cost, volume, and energy efficiency, despite a more complex module architecture. Making careful assumptions on material costs, we provide a cost breakdown for mCDI, HCDI, and IDI modules and show that IDI is the only concept that is not dominated by ion exchange membrane costs. The environmental impact of electrochemical water deionization is illustrated by estimating the carbon footprint of currently installed reverse osmosis capacity in different world regions and comparing it to the respective carbon footprint of mCDI, HCDI, and IDI at similar capacity.

A promising approach to increasing freshwater availability is the effective desalination of widely available and abundant low-salinity water sources. Here we report a new approach to desalinate low-salinity water sources using inexpensive ion exchange resins (IER) which are commonly used for water softening and require regular chemical regeneration. We incorporate IER into a functional composite material that enables electrical regeneration of IER, eliminating the need for regular use of corrosive chemicals. These proof-of-concept results demonstrate reliable regeneration of IER-composite electrodes using a lab-scale prototype device. With further characterization and development, this new approach offers a path to sustainable use of conventional IER for desalination of low-salinity water sources.

Desalination of brackish water sources is critical to addressing the growing global freshwater demand. One promising approach is electrically driven desalination using intercalation electrodes. While intercalation electrodes have been widely researched for energy storage applications, only a small subset of those materials is suitable for desalination. Here we report the synthesis, characterization, and in-device testing of three Prussian blue analogue intercalation compounds: copper, manganese, and zinc hexacyanoferrate with formulas KxM[Fe(CN)6]z·nH2O (M = Cu, Mn, Zn). The desalination performance for each of these materials against carbon electrodes is reported for Na+ intercalation and for Ca2+ intercalation using 1000 ppm NaCl and 1000 ppm CaCl2 feed solutions, respectively. While the copper and manganese analogs showed promising performance for Na+ and Ca2+ intercalation, the zinc compound was unstable and underwent rapid dissolution. Manganese hexacyanoferrate showed the best desalination performance in terms of salt removal capacities and salt removal rates with NaCl while copper hexacyanoferrate performed the best with CaCl2. The manganese analog proved to be the most stable intercalation material, retaining 83% and 72% of its salt removal capacity after 280 cycles in NaCl and CaCl2 feed solutions respectively.

In Asia, access to drinking water is a major issue because of the intrusion of saline groundwater in many areas. Water containing a high concentration of salts is unsuitable for human consumption. The situation is expected to get worse as a result of climate change. This report suggests the development of a ‘road map’ for scalable, low energy-input solutions for small-scale desalination.

A new polymorph of Bi 2 (SO 4 ) 3 was prepared by reaction of LiBiO 2 with H 2 SO 4 and its crystal structure was solved from X-ray powder diffraction. This new polymorph crystallizes in C 2/ c space group with lattice parameters a = 17.3383(3) A, b = 6.77803(12) A, c = 8.30978(13) A, β = 101.4300(12)°. Bi 2 (SO 4 ) 3 presents a layered structure made of SO 4 sulfate groups and signs of stereochemically active Bi 3+ lone pairs. The new Bi 2 (SO 4 ) 3 absorbs water to form Bi 2 (H 2 O) 2 (SO 4 ) 2 (OH) 2 through an intermediate Bi 2 O(OH) 2 SO 4 phase, and the transition is reversible when heated under vacuum.

There is a need for conducting, porous, and chemically stable materials for technologies including, but not limited to, fuel cells, solar cells, and batteries. The need for catalyst support materials that are more durable than carbon black in fuel cells motivated previous studies of the synthesis, characterization, and corrosion resistance of Ti(0.7) W(0.3) O(2) nanoparticles. However, because even higher porosity and increased electrical conductivity are desired, processes were developed to prepare rutile phase Ti(0.7) W(0.3) O(2) and cubic Ti(0.7) W(0.3) N in inverse opal morphologies from a precursor inverse opal of very poorly conducting, amorphous Ti(0.7) W(0.3) O(2.3) . Inverse opals have been explored for a variety of applications from catalysis to photonics, and inverse opals of both oxides and nitrides have been reported. By synthesizing highly conducting mixed-metal oxides and mixed-metal nitrides, the applications of inverse opals can be broadened. Herein, the synthesis and characterization of polystyrene-templated, single-phase, crystalline inverse opals of Ti(0.7) W(0.3) O(2) are reported. These conducting inverse opals can subsequently be converted to inverse opals of Ti(0.7) W(0.3) N and then fully oxidized back to inverse opals of the original insulating, amorphous Ti(0.7) W(0.3) O(2.3) . Such changes in composition and crystal structure, while successfully retaining the inverse opal morphology without the use of a supporting template during the conversion, have not been previously reported.

International audience; Previously reported lithium bismuth oxides, LiBiO2, LiBiO3, Li3BiO3, Li3BiO4, Li5BiO5, and Li7BiO6 were prepared either via ceramic or hydrothermal synthesis methods, and their feasibility as lithium battery cathode materials was tested. None of the oxides showed any desirable electrochemical activity at higher potentials, except for the limited capacity observed during the first discharge in LiBiO3. In contrast, these phases uptake large amounts of Li+ via conversion reactions when cycled down to zero volt, but the reversibility is poor. The transformation of LiBiO3 to LiBiO2 and Li3BiO3 to Li3BiO4 observed via X-ray diffraction showed absence of intermediate phases with mixed Bi3+/Bi5+ oxidation states. Among the materials studied, the highest ionic conductivity of 3.8 x 10(-8) S/cm at 25 degrees C was measured for LiBiO2. The Li+ conduction pathways deduced from bond valence energy landscape approach suggest the best Li diffusion characteristics in Li7BiO6 among the Li-Bi-O phases studied. (C) 2015 Published by Elsevier B.V.

A new silver nitride, AgTaN 2 , was synthesized from NaTaN 2 by a cation-exchange reaction, using a AgNO 3 –NH 4 NO 3 flux at 175 °C. Its crystal structure type is delafossite (R3¯m) with hexagonal lattice parameters of a =3.141(3) A, c =18.81(2) A, in which silver is linearly coordinated to nitrogen. Energy dispersive X-ray analysis and combustion nitrogen/oxygen analysis gave a composition with atomic ratios of Ag:Ta:N:O as 1.0:1.2(1):2.1(1):0.77(4), which is somewhat Ta rich and indicates some oxide formation. The X-ray photoelectron spectroscopy analysis showed a Ta- and O-rich surface and transmission electron microscope observation exhibited aggregates of ca. 4–5 nm-sized particles on the surface, which are probably related to the composition deviation from a AgTaN 2 . The lattice parameters of stoichiometric AgTaN 2 calculated by density functional theory agree with the experimental ones, but the possibility of some oxygen incorporation and/or silver deficiency is not precluded.

A new polymorph of Bi 2 (SO 4 ) 3 was prepared by reaction of LiBiO 2 with H 2 SO 4 and its crystal structure was solved from X-ray powder diffraction. This new polymorph crystallizes in C 2/ c space group with lattice parameters a = 17.3383(3) A, b = 6.77803(12) A, c = 8.30978(13) A, β = 101.4300(12)°. Bi 2 (SO 4 ) 3 presents a layered structure made of SO 4 sulfate groups and signs of stereochemically active Bi 3+ lone pairs. The new Bi 2 (SO 4 ) 3 absorbs water to form Bi 2 (H 2 O) 2 (SO 4 ) 2 (OH) 2 through an intermediate Bi 2 O(OH) 2 SO 4 phase, and the transition is reversible when heated under vacuum.

The current materials used in proton-exchange membrane fuel cells (PEMFCs) are not sufficiently durable for commercial deployment. One of the major challenges lies in the development of an inexpensive, efficient, and CO-tolerant anode catalyst. Here we report the unique CO-tolerant property of Pt nanoparticles supported on Ti(0.7)W(0.3)O(2). The Ti(0.7)W(0.3)O(2) nanoparticles (50 nm) were synthesized via a sol-gel process and platinized using an impregnation-reduction technique. Electrochemical studies of Pt/Ti(0.7)W(0.3)O(2) show unique CO-tolerant electrocatalytic activity for hydrogen oxidation compared to commercial E-TEK PtRu/C catalysts. Differential electrochemical mass spectrometry measurements show the onset potential for CO oxidation on Pt/Ti(0.7)W(0.3)O(2) to be below 0.1 V (vs RHE). Pt/Ti(0.7)W(0.3)O(2) is a promising new anode catalyst for PEMFC applications.

The title compounds are prepared by ball milling of mixtures of LiOH and anhydrous MSO4 (M: Fe, Co, Mn) precursors.

International audience; The Li-ion rechargeable battery, due to its high energy density, has driven remarkable advances in portable electronics. Moving toward more sustainable electrodes could make this technology even more attractive to large-volume applications. We present here a new family of 3d-metal hydroxysulfates of general formula LiMSO4OH (M = Fe, Co, and Mn) among which (i) LiFeSO4OH reversibly releases 0.7 Li+ at an average potential of 3.6 V vs Li+/Li0, slightly higher than the potential of currently lauded LiFePO4 (3.45 V) electrode material, and (ii) LiCoSO4OH shows a redox activity at 4.7 V vs Li+/Li0. Besides, these compounds can be easily made at temperatures near 200 °C via a synthesis process that enlists a new intermediate phase of composition M3(SO4)2(OH)2 (M = Fe, Co, Mn, and Ni), related to the mineral caminite. Structurally, we found that LiFeSO4OH is a layered phase unlike the previously reported 3.2 V tavorite LiFeSO4OH. This work should provide an impetus to experimentalists for designing better electrolytes to fully tap the capacity of high-voltage Co-based hydroxysulfates, and to theorists for providing a means to predict the electrochemical redox activity of two polymorphs.

The materials currently used in proton-exchange membrane fuel cells (PEMFCs) require complex control of operating conditions to make them sufficiently durable to permit commercial deployment. One of the major materials challenges to allow simplification of fuel cell operating strategies is the discovery of catalyst supports that are much more stable to oxidative decomposition than currently used carbon blacks. Here we report the synthesis and characterization of Ti(0.7)W(0.3)O2 nanoparticles (approximately 50 nm diameter), a promising doped metal oxide that is a candidate for such a durable catalyst support. The synthesized nanoparticles were platinized, characterized by electrochemical testing, and evaluated for stability under PEMFC and other oxidizing acidic conditions. Ti(0.7)W(0.3)O2 nanoparticles show no evidence of decomposition when heated in a Nafion solution for 3 weeks at 80 °C. In contrast, when heated in sulfuric, nitric, perchloric, or hydrochloric acid, the oxide reacts to form salts such as titanylsulfatehydrate from sulfuric acid. Electrochemical tests show that rates of hydrogen oxidation and oxygen reduction by platinum nanoparticles supported on Ti(0.7)W(0.3)O2 are comparable to those of commercial Pt on carbon black.

A major challenge in obtaining long-term durability in fuel cells is to discover catalyst supports that do not corrode, or corrode much more slowly than the current carbon blacks used in today’s polymer electrolyte membrane fuel cells. Such materials must be sufficiently stable at low pH (acidic conditions) and high potential, in contact with the polymer membrane and under exposure to hydrogen gas and oxygen at temperatures up to perhaps 120°C. Here, we report the initial discovery of a promising class of doped oxide materials for this purpose: Ti1−xMxO2, where M=a variety of transition metals. Specifically, we show that Ti0.7W0.3O2is electrochemically inert over the appropriate potential range. Although the process is not yet optimized, when Pt nanoparticles are deposited on this oxide, electrochemical experiments show that hydrogen is oxidized and oxygen reduced at rates comparable to those seen using a commercial Pt on carbon black support.

Our laboratory studies the effects of in utero opioid exposure on the neonate. In this work we test the effects of chronic in utero exposure to buprenorphine on the neonate. Buprenorphine is a promising candidate for treatment of opioid addiction during pregnancy and it has been suggested to decrease the neonatal abstinence syndrome in human infants. In our guinea pig model, we focused not only on the respiratory effects of in utero exposure on the neonate, but also studied withdrawal signs in the neonate, a major concern of all opioid treatment during pregnancy. Pregnant guinea pigs were treated with daily subcutaneous injections of 0.1 mg/kg buprenorphine during the second half of gestation. We measured weight, locomotor activity and respiratory function in pups of ages 3 to 14 days. Respiratory response was recorded using a two-chamber plethysmograph, while pups were breathing either room air or 5% CO 2 . Our results show that chronic in utero exposure to buprenorphine induces respiratory effects up to day 14 after birth, while earlier studies have shown that effects of either in utero methadone or morphine only persist in the first week after birth in the guinea pig model. These data provide important information for clinical trials of buprenorphine treatment suggesting that duration and severity of respiratory effects of in utero buprenorphine exposure should be monitored.