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We herein explore a facile and straightforward approach to enhance the interface stability between the lithium superionic conducting Li 10 GeP 2 S 12 (LGPS) solid electrolyte and Li metal by employing ionic liquid such as 1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/ N-methyl- N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR 13 TFSI) as the interface modifier. The results demonstrated the presence of 1 M LiTFSI/PYR 13 TFSI ionic liquid; the interface stability at the electrode/solid electrolyte (i.e., Li/LGPS) was improved remarkably by forming an in situ solid electrolyte interphase (SEI) layer. As a result, an effectively reduced interfacial resistance from 2021 to 142 Ω cm 2 and stable Li stripping/plating performance (over 1200 h at 0.038 mA cm -2 and 1000 h at 0.1 mA cm -2 ) were achieved in the Li/LGPS/Li symmetric cells. On this basis, the Li-S solid-state batteries were further architectured with one of the S@C composite [where C is the ketjen black carbon (KBC) or PBX 51-type activated carbon (PBX51C) or multiwalled carbon nanotubes (MCNTs)] cathode and the LGPS solid electrolyte. The batteries with S@KBC electrodes delivered an excellent discharge/charge performance with a high initial discharge capacity of 1017 mA h g -1 and better stability than those of the batteries with the S@PBX51C and S@MCNTs electrodes. High surface area, unique beneficial pore structure, and better particle dispersion of sulfur in the S@KBC composite facilitate high sulfur utilization and also increase the intimate contact between the electrode and LGPS solid electrolyte during the discharge/charge process.

Heterogeneous catalysis performs on specific sites of a catalyst surface even if specific sites of many catalysts during catalysis could not be identified readily. Design of a catalyst by managing catalytic sites on an atomic scale is significant for tuning catalytic performance and offering high activity and selectivity at a relatively low temperature. Here, we report a synergy effect of two sets of single-atom sites (Ni 1 and Ru 1 ) anchored on the surface of a CeO 2 nanorod, Ce 0.95 Ni 0.025 Ru 0.025 O 2 . The surface of this catalyst, Ce 0.95 Ni 0.025 Ru 0.025 O 2 , consists of two sets of single-atom sites which are highly active for reforming CH 4 using CO 2 with a turnover rate of producing 73.6 H 2 molecules on each site per second at 560 °C. Selectivity for producing H 2 at this temperature is 98.5%. The single-atom sites Ni 1 and Ru 1 anchored on the CeO 2 surface of Ce 0.95 Ni 0.025 Ru 0.025 O 2 remain singly dispersed and in a cationic state during catalysis up to 600 °C. The two sets of single-atom sites play a synergistic role, evidenced by lower apparent activation barrier and higher turnover rate for production of H 2 and CO on Ce 0.95 Ni 0.025 Ru 0.025 O 2 in contrast to Ce 0.95 Ni 0.05 O 2 with only Ni 1 single-atom sites and Ce 0.95 Ru 0.05 O 2 with only Ru 1 single-atom sites. Computational studies suggest a molecular mechanism for the observed synergy effects, which originate at (1) the different roles of Ni 1 and Ru 1 sites in terms of activations of CH 4 to form CO on a Ni 1 site and dissociation of CO 2 to CO on a Ru 1 site, respectively and (2) the sequential role in terms of first forming H atoms through activation of CH 4 on a Ni 1 site and then coupling of H atoms to form H 2 on a Ru 1 site. These synergistic effects of the two sets of single-atom sites on the same surface demonstrated a new method for designing a catalyst with high activity and selectivity at a relatively low temperature.

Despite the extremely high ionic conductivity, the commercialization of Li 10 GeP 2 S 12 -type materials is hindered by the poor stability against Li metal. Herein, to address that issue, a simple strategy is proposed and demonstrated for the first time, i.e., in situ modification of the interface between Li metal and Li 10 SnP 2 S 12 (LSPS) by pretreatment with specific ionic liquid and salts. X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy results reveal that a stable solid electrolyte interphase (SEI) layer instead of a mixed conducting layer is formed on Li metal by adding 1.5 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/ N-propyl- N-methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr 13 TFSI) ionic liquid, where ionic liquid not only acts as a wetting agent but also improves the stability at the Li/LSPS interface. This stable SEI layer can prevent LSPS from directly contacting the Li metal and further decomposition, and the Li/LSPS/Li symmetric cell with 1.5 M LiTFSI/Pyr 13 TFSI attains a stable cycle life of over 1000 h with both the charge and discharge voltages reaching about 50 mV at 0.038 mA cm -2 . Furthermore, the effects of different Li salts on the interfacial modification is also compared and investigated. It is shown that lithium bis(fluorosulfonyl) imide (LiFSI) salt causes the enrichment of LiF in the SEI layer and results in a higher resistance of the cell upon a long cycling life.

Artificial microbial nitrogen (N) cycle hotspots in the plant-bed/ditch system were developed and investigated based on intact core and slurry assays measurement using isotopic tracing technology, quantitative PCR and high-throughput sequencing. By increasing hydraulic retention time and periodically fluctuating water level in heterogeneous riparian zones, hotspots of anammox, nitrification, denitrification, ammonium (NH 4 + ) oxidation, nitrite (NO 2 - ) oxidation, nitrate (NO 3 - ) reduction and DNRA were all stimulated at the interface sediments, with the abundance and activity being about 1-3 orders of magnitude higher than those in nonhotspots. Isotopic pairing experiments revealed that in microbial hotspots, nitrite sources were higher than the sinks, and both NH 4 + oxidation (55.8%) and NO 3 - reduction (44.2%) provided nitrite for anammox, which accounted for 43.0% of N-loss and 44.4% of NH 4 + removal in riparian zones but did not involve nitrous oxide (N 2 O) emission risks. High-throughput analysis identified that bacterial quorum sensing mediated this anammox hotspot with B.fulgida dominating the anammox community, but it was B. anammoxidans and Jettenia sp. that contributed more to anammox activity. In the nonhotspot zones, the NO 2 - source (NO 3 - reduction dominated) was lower than the sink, limiting the effects on anammox. The in situ N 2 O flux measurement showed that the microbial hotspot had a 27.1% reduced N 2 O emission flux compared with the nonhotspot zones.

The development of highly reversible multielectron reaction per redox center in sodium super ionic conductor-structured cathode materials is desired to improve the energy density of sodium-ion batteries. Here, we investigated more than one-electron storage of Na in Na 3 VCr(PO 4 ) 3 . Combining a series of advanced characterization techniques such as ex situ 51 V solid-state nuclear magnetic resonance, X-ray absorption near-edge structure, and in situ X-ray diffraction, we reveal that V 3+ /V 4+ and V 4+ /V 5+ redox couples in the materials can be accessed, leading to a 1.5-electron reaction. It is also found that a light change on the local electronic and structural states or phase change could be observed after the first cycle, resulting in the fast capacity fade at room temperature. We also showed that the irreversibility of the phase changes could be largely suppressed at low temperature, thus leading to a much improved electrochemical performance.

In this communication, a novel electrolyte additive, N,N-diallyic-diethyoxyl phosphamide (DADEPA), is described for the first time to improve the thermal stability of lithiated graphite anode in Li-ion batteries. The differential scanning calorimetry (DSC) measurement demonstrated that when the graphite was lithiated in the 5% DADEPA-containing electrolyte, the heat generation decreased sharply by half as compared with the reference, whereas the onset temperature for the main exothermic process was postponed by 20 °C. Electrochemical and XPS analyses indicated that the distinctive improvement in thermal safety came from a new interfacial chemistry, in which phosphorus-containing ingredients was embedded during the initial forming of the interphase.