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Atomic layer deposition (ALD) has been gaining in popularity as a powerful deposition technique and have been shown to be a promising interfacial engineering method to boost the electrochemical performance of supercapacitors, bridging the gap in energy density. In that regard, we developed an ALD technique to deposit titanium dioxide (TiO2) nanofilms onto porous activated carbon (AC) electrodes. This study focused on the critical aspects of the ALD process that were still unexplored by previous relevant works, including the effects of precursor pulse duration and film thickness on the complex porous structures of AC. In particular, these comprehensive investigations pave the way towards uniform distribution and excellent conformity of the TiO2 nanofilms across the AC surface. Moreover, the deposited films were found to be amorphous and resulted in increased amounts of oxygen-containing surface functional groups. The enhanced electrochemical behavior from the TiO2 nanofilms were found to be optimal at 60 ALD cycles with an estimated film thickness of 2.3 nm. The assembled supercapacitor device coated with this ALD technique exhibited higher specific capacitance compared to the bare AC. The key findings of this work provide the foundation of an effective strategy using ALD for fabricating new electrode materials for high-performance supercapacitors. 

We report a family of cobalt complexes based on bidentate phosphine ligands with two, one, or zero pendent amine groups in the ligand backbone. The pendent amine complexes are active electrocatalysts for the formate oxidation reaction, generating CO2 with near-quantitative faradaic efficiency at moderate overpotentials (0.45 – 0.57 V in acetonitrile). These homogeneous electrocatalysts are the first cobalt example and second first-row transition metal example for formate oxidation. Thermodynamic measurements reveal these complexes are energetically primed for formate oxidation via hydride transfer to the cobalt center, followed by deprotonation of the resulting cobalt-hydride by formate acting as a base. The complex with the strongest cobalt- hydride bond, given by its thermodynamic hydricity, is the fastest electrocatalyst in this series, with an observed rate constant for formate oxidation of 135 ± 8 h−1 at 25 °C. Electrocatalytic turnover is not observed for the complex with no pendent amine groups: decomposition of the complex structure is evident in the presence of high formate concentrations. 

Natural behaviors are a coordinated symphony of motor acts that drive reafferent (self-induced) sensory activation. Individual sensors cannot disambiguate exafferent (externally induced) from reafferent sources. Nevertheless, animals readily differentiate between these sources of sensory signals to carry out adaptive behaviors through corollary discharge circuits (CDCs), which provide predictive motor signals from motor pathways to sensory processing and other motor pathways. Yet, how CDCs comprehensively integrate into the nervous system remains unexplored. Here, we use connectomics, neuroanatomical, physiological, and behavioral approaches to resolve the network architecture of two pairs of ascending histaminergic neurons (AHNs) in Drosophila, which function as a predictive CDC in other insects. Both AHN pairs receive input primarily from a partially overlapping population of descending neurons, especially from DNg02, which controls wing motor output. Using Ca2+ imaging and behavioral recordings, we show that AHN activation is correlated to flight behavior and precedes wing motion. Optogenetic activation of DNg02 is sufficient to activate AHNs, indicating that AHNs are activated by descending commands in advance of behavior and not as a consequence of sensory input. Downstream, each AHN pair targets predominantly non-overlapping networks, including those that process visual, auditory, and mechanosensory information, as well as networks controlling wing, haltere, and leg sensorimotor control. These results support the conclusion that the AHNs provide a predictive motor signal about wing motor state to mostly non-overlapping sensory and motor networks. Future work will determine how AHN signaling is driven by other descending neurons and interpreted by AHN downstream targets to maintain adaptive sensorimotor performance. 

Reaction of FeBr 2 with 1.5 equiv. of LiNCPh 2 and 2 equiv. of Zn, in THF, results in the formation of the tetrametallic iron ketimide cluster [Fe 4 (NCPh 2 ) 6 ] ( 1 ) in moderate yield. Formally, two Fe centers in 1 are Fe( i ) and two are Fe( ii ); however, Mössbauer spectroscopy and SQUID magnetometry suggests that the [Fe 4 ] 6+ core of 1 exhibits complete valence electron delocalization, with a thermally-persistent spin ground state of S = 7. AC and DC SQUID magnetometry reveals the presence of slow magnetic relaxation in 1 , indicative of single-molecule magnetic (SMM) behaviour with a relaxation barrier of U eff = 29 cm −1 . Remarkably, very little quantum tunnelling or Raman relaxation is observed down to 1.8 K, which leads to an open hysteresis loop and long relaxation times (up to 34 s at 1.8 K and zero field and 440 s at 1.67 kOe). These results suggest that transition metal ketimide clusters represent a promising avenue to create long-lifetime single molecule magnets.