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The development of a nonprecious, stable, and highly effective electrocatalyst for decomposition of water into oxygen and hydrogen is vitally important for sustainable energy conversion, but it still remains challenging to replace the noble metal electrocatalysts with more economically viable alternatives. Herein, a polyaniline (PANI) decorated hierarchical nickel cobalt thiospinel (NiCo2S4) hybrid catalyst (NCS-P) has been developed that shows enhanced dual catalytic activity for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) compared to pristine NiCo2S4 (NCS). Benefiting from the conductive PANI coating, the hierarchical NCS-P nanostructure exhibits outstanding electrocatalytic activity in alkaline solution with low overpotentials of 273 ± 3 and 77 ± 4 mV at 10 mA cm−2 and low Tafel slopes of 42.2 and 68.5 mV dec−1 for OER and HER, respectively, which are better than those of the benchmark noble-metal-based RuO2 and Pt/C.

Molecular chirality is represented as broken mirror symmetry in the structural orientation of constituent atoms and plays a pivotal role at every scale of nature. Since the discovery of the chiroptic property of chiral molecules, the characterization of molecular chirality is important in the fields of biology, physics, and chemistry. Over the centuries, the field of optical chiral sensing was based on chiral light–matter interactions between chiral molecules and polarized light. Starting from simple optics-based sensing, the utilization of plasmonic materials that could control local chiral light–matter interactions by squeezing light into molecules successfully facilitated chiral sensing into noninvasive, ultrasensitive, and accurate detection. In this Review, the importance of plasmonic materials and their engineering in chiral sensing are discussed based on the principle of chiral light–matter interactions and the theory of optical chirality and chiral perturbation; thus, this Review can serve as a milestone for the proper design and utilization of plasmonic nanostructures for improved chiral sensing. [ABSTRACT FROM AUTHOR]

Due to the detrimental effects of CO2 on the atmosphere, including climate change, the development of environmentally friendly electrocatalysts for CO2 reduction is crucial for mitigation. Inspired by carbon monoxide dehydrogenase (CODH) enzymes, where an active centre is surrounded by a protein scaffold, this work introduces a biomimetic system featuring a vitamin B12 cluster protected by a matrix of multi-walled carbon nanotubes (MWCNTs). Unlike literature-based vitamin B12 systems with no redox activity, we have developed multi-walled nanotubes (MWCNTs) functionalized with vitamin B12 (MWCNT@B12) as a highly redox-active system and explored it for electrocatalytic CO2 reduction reaction at room temperature in an aqueous medium. The presence of vitamin B12 in the matrix was confirmed through a series of characterizations by employing FTIR, Raman spectroscopy, FESEM, EDAX, ultrapressure liquid chromatography (UPLC), scanning electrochemical microscopy (SECM) and cyclic voltammetry. This new electrocatalyst demonstrates high faradaic efficiency (∼100%), low overpotential (ηCO2 = 242 mV), and a significant current density (43.5 mA cm−2) for the electrocatalytic conversion of CO2 to CO in a 0.5 M NaHCO3 solution. In situ SECM reveals that clusters of vitamin B12 embedded on the modified electrode are the active sites for the overall electrocatalytic reaction. Compared to previously reported heterogeneous molecular catalyst electrodes, this system exhibits a lower peak-reduction potential of 100–600 mV and current densities 2–40 times higher for the CO2 reduction reaction. Furthermore, vitamin B12 is a naturally occurring, non-toxic redox mediator. Therefore, the B12-modified electrode presented herein is a promising development for future green CO2 reduction applications. [ABSTRACT FROM AUTHOR]

Materials generating circularly polarized luminescence (CPL) have received increasing interest due to their potential applications in bioimaging, sensing, anticounterfeiting, and display technologies. The possibility of efficient CPL generation is explored for organic molecules, inorganic materials, and their hybrid systems. A chiral plasmonic nanostructure is one candidate for generating strong and highly dissymmetric CPL by coupling with the surrounding luminescent material. Here, the inherent luminescence of gold nanoparticles can produce CPL without using any secondary material is suggested. In this study, the generation of circularly polarized two‐photon‐induced photoluminescence (TPI‐PL) from chiral gold nanostructures is demonstrated. Measurements of TPI‐PL show that it has a strong dissymmetry factor of ≈0.7 for a single chiral Au nanoparticle. A theoretical simulation study showed that a local chiral electromagnetic field confined to the chiral gap structures contributes to the high degree of circular polarization in TPI‐PL. It is believed that this work provides a new route for novel CPL‐generating materials with strong dissymmetry and holds promise for various applications using CPL technology. [ABSTRACT FROM AUTHOR]

Opto-neuromorphic operation is critical for biological system to recognize the visual objects and mimicking such operation is important for artificial prosthesis as well as machine vision system for industrial applications. To sophisticatedly mimic biological system, regulation of learning and memorizing efficiency is needed, however engineered synthetic platform has been lack of controllability, which makes huge gap between biological system and synthetic platform. Here we demonstrated controllable learning and memorizing opto-neuromorphic operation at plasmonic hot electron transistor. Especially, circularly polarized light (CPL) sensitive synaptic characteristics and learning experience capability are enabled by incorporating chiral plasmonic nanoparticle. Furthermore, gate voltage gives rise to controllable neuromorphic operation due to hot electron injection and trapping effect, resulting in high remaining synaptic weight of ∼70% at negative gate voltage under CPL excitation. We believe that this discovery makes significant leap toward on-demand in-sensor computing as well as toward bio-realistic device. [ABSTRACT FROM AUTHOR]

To compare the visual outcome and fluid features of a proposed biosimilar, CKD-701, versus the reference ranibizumab in eyes with polypoidal choroidal vasculopathy (PCV). This was a post hoc analysis of a phase 3 randomized clinical trial assessing the efficacy and safety of CKD-701 and ranibizumab. A total of 73 PCV eyes were assigned randomly to either CKD-701 (36 eyes) or ranibizumab (37 eyes). The mean changes in best-corrected visual acuity (BCVA), central retinal thickness (CRT), pigment epithelial detachment (PED) volume, and fluid features were compared. After three loading injections, the mean change in BCVA (letters) was +7.50 in the CKD-701 group and +6.32 in the ranibizumab group (p =.447). The changes in CRT and PED volume of the CKD-701 group (−107.25 ± 102.66 μm and −0.22 ± 0.46 mm3) were similar to those of the ranibizumab group (−96.78 ± 105.00 μm and −0.23 ± 0.54 mm3) (p =.668 and p =.943, respectively). Proportions of eyes with subretinal, intraretinal and sub-retinal pigment epithelium (RPE) fluids after three loading injections were not different between CKD-701 group (33.3%, 13.9% and 42.9%) and ranibizumab group (51.4%, 16.2% and 40.0%) (p =.071, p = 1.000 and p =.808). The visual and anatomical changes were similar between two groups at month 6 and 12 (all, p >.05). Biosimilar CKD-701 monotherapy resulted in comparable visual and anatomical changes to those achieved with reference ranibizumab in PCV eyes. [ABSTRACT FROM AUTHOR]