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Non‐native plants are typically released from specialist enemies but continue to be attacked by generalists, albeit at lower intensities. This reduced herbivory may lead to less investment in constitutive defences and greater investment in induced defences, potentially reducing defence costs. We compared herbivory on 27 non‐native and 59 native species in the field and conducted bioassays and chemical analyses on 12 pairs of non‐native and native congeners. Non‐natives suffered less damage and had weaker constitutive defences, but stronger induced defences than natives. For non‐natives, the strength of constitutive defences was correlated with the intensity of herbivory experienced, whereas induced defences showed the reverse. Investment in induced defences correlated positively with growth, suggesting a novel mechanism for the evolution of increased competitive ability. To our knowledge, these are the first linkages reported among trade‐offs in plant defences related to the intensity of herbivory, allocation to constitutive versus induced defences, and growth.

 

Improved performance of lithium-ion batteries (LIBs) plays a critical role in the future of next- generation battery applications. Nickel-rich layered oxides such as LiNi_0.8Mn_0.1Co_0.1O₂(NMC 811), are popular cathodes due to their high energy densities. However, they suffer from high surface reactivity, which results in the formation of Li₂CO₃passive layer. Herein, we show the role of nanosecond pulsed laser annealing (PLA) in improving the current capacity and cycling stability of LIBs by reducing the carbonate layer, in addition to forming a protective LiF layer and manipulating the NMC 811 microstructures. We use high-power nanosecond laser pulses in a controlled way to create nanostructured surface topography which has a positive impact on the capacity retention and current capacity by providing an increased active surface area, which influences the diffusion kinetics of lithium-ions in the electrode materials during the battery cycling process. Advanced characterizations show that the PLA treatment results in the thinning of the passive Li₂CO₃layer, which is formed on as-received NMC811 samples, along with the decomposition of excess polyvinylidene fluoride (PVDF) binder. The high-power laser interacts with the decomposed binder and surface Li⁺to form LiF phase, which acts as a protective layer to prevent surface reactive sites from initiating parasitic reactions. As a result, the laser treated cathodes show relative increase of the current capacity of up to 50%, which is consistent with electrochemical measurements of LiB cells.

 

While chirality imbalances are forbidden in conventional lattice systems, non-Hermiticity can effectively avoid the chiral-doubling theorem to facilitate 1D chiral dynamics. Indeed, such systems support unbalanced unidirectional flows that can lead to the localization of an extensive number of states at the boundary, known as the non-Hermitian skin effect (NHSE). Recently, a generalized (rank-2) chirality describing a 2D robust gapless mode with dispersionω = k_xk_yhas been introduced in crystalline systems. Here we demonstrate that rank-2 chirality imbalances can be established in a non-Hermitian (NH) lattice system leading to momentum-resolved chiral dynamics, and a rank-2 NHSE where there are both edge- and corner-localized skin modes. We then experimentally test this phenomenology in a 2-dimensional topolectric circuit that implements a NH Hamiltonian with a long-lived rank-2 chiral mode. Using impedance measurements, we confirm the rank-2 NHSE in this system, and its manifestation in the predicted skin modes and a highly unusual momentum-position locking response. Our investigation demonstrates a circuit-based path to exploring higher-rank chiral physics, with potential applications in systems where momentum resolution is necessary, e.g., in beamformers and non-reciprocal devices.

 

Cost-effective production of low cobalt Li-ion battery (LIB) cathode materials is of great importance to the electric vehicle (EV) industry to achieve a zero-carbon economy. Among the various low cobalt cathodes, Ni-rich lithium nickel cobalt manganese oxide (NCM/NMC)-based layered materials are commonly used in EVs and are attracting more attention of the scientific community due to their high specific capacity and energy density. Various synthesis routes are already established to produce Ni-rich NCM cathodes with uniform particle size distribution and high tap density. Continuous production of highly pure Ni-rich cathode materials with uniformity in inter/intra-particle compositional distribution is critically required. On the other hand, cation mixing, particle cracking, and parasitic side reactions at higher voltage and temperature are some of the primary challenges of working with Ni-rich NCM cathodes. During the past five years, several advanced modification strategies such as coating, doping, core–shell, gradient structure and single crystal growth have been explored to improve the NCM cathode performance in terms of specific capacity, rate-capability and cycling stability. The scientific advancements in the field of Ni-rich NCM cathodes in terms of manufacturing processes, material challenges, modification techniques, and also the future research direction of LIB research are critically reviewed in this article.