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Sodium‐oxygen batteries are emerging as new battery systems. Deep understanding of the origin of overpotential and the kinetic process in sodium‐oxygen batteries remain challenging yet critical. We apply a method of distribution of relaxation time (DRT) to decipher the electrochemical impedance spectroscopy (EIS), allowing us to monitor the changes of different kinetic processes during the discharging and charging. The origin of the overpotential in a battery was further comprehensively investigated combining DRT analysis with differential electrochemical mass spectrometry, Raman and other characterizations. Overpotential is found to primarily stem from oxygen mass transport during discharging, and from poor solid‐solid contact at the electrode surface during charging. Our work demonstrates the study of kinetic processes using DRT analysis, and suggests effective ways to improve the performances of sodium‐oxygen batteries. [ABSTRACT FROM AUTHOR]

Decorating plasmonic Au nanoparticles on TiO2 nanotube arrays with high specific surface area is an efficient strategy for constructing high-performance surface-enhanced Raman scattering (SERS) substrates. Direct deposition of a Au thin film on a TiO2 support, followed by dewetting at elevated temperatures, is economical for scale-up production of Au nanoparticles. The thermal diffusion behavior of Au on a high-curvature surface, however, makes it difficult to meet an optimized distribution of Au nanoparticles that is required for forming electromagnetic SERS hotspot regions. Herein, we proposed a layer-by-layer deposition method to prepare Au-decorated TiO2 nanotube arrays using ZnO nanowires as structural templates. Au nanoparticles could be loaded on either the interior or exterior of the TiO2 nanotubes or buried in the walls simply by switching the sequence of magnetron sputtering of Au and atomic layer deposition of TiO2. We revealed that regulating the thermal diffusion of the Au thin film in the confined ZnO/TiO2 interlayer favors an optimal distribution of the dewetted Au nanoparticles at the interstices. By virtue of the size and interspace of the Au nanoparticles balancing each other, Au–TiO2 featuring Au nanoparticles dispersed on the inner walls of TiO2 nanotubes provided abundant localized electromagnetic field hot spots with a small amount of Au consumption. This Au–TiO2 substrate presented high SERS activity, e.g. a detection limit of 10−9 M for the R6G molecule. This substrate could also achieve self-cleaning through photocatalytic degradation of adsorbed organic analytes, which is required for repeated SERS sensing. [ABSTRACT FROM AUTHOR]

Rechargeable sodium‐carbon dioxide batteries utilize CO2 directly and use abundant and low‐cost sodium instead of lithium. Sodium carbonate is an important discharge product in Na‐CO2 batteries and its oxidative decomposition during charging determines cell performance (i.e., overpotentials and cyclability) but the decomposition mechanism has not been addressed yet. Herein, it is found that Na2CO3 decomposition during the charging process follows a different pathway to lithium carbonate decomposition. It proceeds via a reactive CO3•− intermediate instead of a singlet oxygen intermediate, and thus CO and O2 evolution are not identified during charging. Calculation results show that the OO distance between two adjacent CO3•− in solid Na2CO3 is longer than that in lithium carbonate and thus forming the C2O62− dimer and singlet oxygen is kinetically disfavored in Na2CO3. Surprisingly, the carbon element in Na2CO3 and carbon substrate can exchange via a Na2CO3•C composite after ball milling. By forming the Na2CO3•C composite, carbon can participate in the charging process and be fully oxidized. Therefore, designing a catalyst to encourage the reversible formation/decomposition of Na2CO3•C might be the key to realizing the reversible cycling of Na‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Background: Anti‐synthetase syndrome (ASS) is a chronic multisystemic autoimmune disease characterized by detectable anti‐aminoacyl‐transfer‐RNA antibodies. Interstitial lung disease (ILD) in anti‐synthetase syndrome patients is often severe and rapidly progressive. Anti‐Zo (phenylalanyl) antibody is reported rarely in ASS. Therefore, the appropriate treatment of anti‐Zo positive ASS is unclear. Case presentation: Here we present a case of anti‐Zo‐positive ASS with rapid progressive ILD (RP‐ILD) in a Chinese patient successfully treated with a combination of systemic corticosteroids and tacrolimus. Conclusion: We reviewed 13 anti‐Zo‐positive ASS patients (including our case) and summarized clinical features that have some differences with other ASS. Anti‐Zo‐positive ASS is a rare autoimmune disease with a high burden of ILD, is often severe and rapidly progressive. Corticosteroids with tacrolimus may improve patient outcomes in anti‐Zo antibody positive ASS with RP‐ILD. [ABSTRACT FROM AUTHOR]

Efficient catalysts are highly desirable for the selective electrochemical CO2 reduction reaction (CO2RR). Ni single-atom catalysts are known as promising CO2RR catalysts, while Ni NPs are expected to catalyze the competing HER. In this work, we have modified the Ni NPs by encapsulating them into porous Ni–N–C nanosheets (Ni@Ni–N–C), to boost the synergy between Ni NPs and dispersed Ni–N species towards CO2RR. The CO faradaic efficiency (FECO) reached 96.4% at −0.9 V and retained over 90% in a wide potential window. More importantly, FECO values of over 94% have been obtained from −50 to −170 mA cm−2 with a peak FECO of 99% in a flow cell. Our work demonstrates that the surface modification of Ni NPs can inhibit the unexpected HER and activate the surface sites, offering a practical design strategy for CO2RR catalysts. [ABSTRACT FROM AUTHOR]

In this paper, we present an effective route for boosting the photoelectrochemical overall water splitting to produce hydrogen and oxygen by modified TiO2 nanowire arrays (NWAs) photoanode. Such modification includes the synthesis of branched TiO2 NWAs and followed by the deposition of Au nanoparticles (NPs) via the magnetron sputtering and post-annealing for the dewetting of Au films. The physical deposition of Au on the TiO2 substrate with a hierarchical structure provides a feasible strategy to produce metal NPs with uniform size and distribution by the space confinement of the branched TiO2 NWAs. Those Au NPs rendered the intensified visible light absorption in a narrow band region due to the surface plasmon resonance (SPR) effect. The amplified electromagnetic field through the SPR excitation of the Au NPs and their passivation upon the surface of TiO2 NWAs led to the efficient generation and transfer of charge carriers. The synergistic effect between branched TiO2 NWAs and Au NPs resulted in the drastic enhancement of the photoelectrochemical overall water splitting to produce hydrogen and oxygen in the stoichiometric ratio. This work provides a facile method for the preparation of hierarchical metal/semiconductor composite photoelectrode with great potential in the efficient photoelectrochemical water splitting for hydrogen energy production and other applications in solar energy conversion. [ABSTRACT FROM AUTHOR]