Intrinsic Energy Research Articles

Optical imaging of the stochastic nucleation kinetics and intrinsic activation energy of single spin-crossover nanoparticles

Cooperative spin crossover (SCO) compounds are one of the most promising molecular bistable solids due to their intriguing thermal hysteresis phenomena around room temperature. It is well known that hysteresis is an essential kinetic effect, however, accurate assessment of the spin transition kinetics of SCO nanomaterials remains scarce. Herein, we developed a thermal-optical methodology to image the thermally induced spin transition kinetics of single SCO nanoparticles in a quantitative, repeatable, and high-throughput manner. Single-particle measurement revealed an intrinsic nucleation-dominated spin transition mechanism, where a highly stochastic nucleation process was clearly observed during the repeatable measurements. By quantifying the dependence of nucleation time on temperature, the activation energy barriers for nucleation were further extracted at a single particle level. Based on this foundation, the high throughput of the optical imaging not only contributed to uncovering the significant nanoparticle-to-nanoparticle heterogeneity, with implications for a negative correlation between apparent activation energy barriers for nucleation and size of the SCO nanoparticles, but also facilitated identifying a minority with high activation energy at least twice the average value. The extraordinary performance was then attributed to the fewer defects within their structures, as confirmed by further results from the in situ creation of defects by thermal ablation, thereby setting the lower limit for the intrinsic activation energy of ideal SCO crystals and promising their potential for future applications in high-performance molecular devices.

Energy landscape of conformational changes for a single unmodified protein

Resolving the free energy landscapes that govern protein biophysics has been obscured by ensemble averaging. While the folding dynamics of single proteins have been observed using fluorescent labels and/or tethers, a simpler and more direct measurement of the conformational changes would not require modifications to the protein. We use nanoaperture optical tweezers to resolve the energy landscape of a single unmodified protein, Bovine Serum Albumin (BSA), and quantify changes in the three-state conformation dynamics with temperature. A Markov model with Kramers’ theory transition rates is used to model the dynamics, showing good agreement with the observed state transitions. This first look at the intrinsic energy landscape of proteins provides a transformative tool for protein biophysics and may be applied broadly, including mapping out the energy landscape of particularly challenging intrinsically disordered proteins.

Alkylation of low eutectic energy-containing carrier molecules: Design and synthesis

A novel low eutectic energy-carrying carrier molecule has been developed that satisfies three criteria: intrinsic energy, effective lowering of the melting point of other carriers, and a wide range of thermal stability. In this study, two new compounds, APAD1 and APAD2, were synthesized by alkylation of molecular side groups and their structures were confirmed by FT-IR, NMR, and XRD. The melting points of APAD1 and APAD2 were 117 °C and 97 °C, respectively, and the decomposition temperatures were 266 °C and 242 °C, respectively, which were significantly lower compared to DATNEB. This method extends the synthesis of low eutectic carrier molecules for composite casting.

Fracture of polymer-like networks with hybrid bond strengths

The design and functionality of polymeric materials hinge on failure resistance. While molecular-level details drive crack evolution in polymer networks, the connection between individual chain scission and bulk failure remains unclear and difficult to probe. In this work, we systematically study the fracture mechanics of polymer-like networks with hybrid bond strengths. We reveal that varying the ratio of strong and weak strands within otherwise identical networks gives a non-monotonic relationship between intrinsic fracture energy and strong strand fraction. Networks with some weak strands can counterintuitively outperform those with exclusively strong strands. Experiments on poly(ethylene glycol) gels and architected polymer-like lattices together with simulations unveil these properties. We show through computational visualization that strand type concentrations impact crack growth patterns and fracture energy trends. Cracks propagate through weak layers at low strong strand fractions. Aggregate clusters deflect or pin cracks at similar concentrations of strong and weak strands. Cracks blunt due to dispersed weak strand failure at high strong strand fractions. The sacrificial weak strands can notably deconcentrate stress near the crack tip, which toughens by delaying crack advancement. The interplay between concentration and clustering of strand types in networks with hybrid bond strengths, combined with crack growth phenomena and nonlocal energy release, provides insights into unusual fracture characteristics. Results shed light on fracture in polymer networks and percolated lattices.

A novel grain refinement of Ce-Fe-B magnets induced by magnetic field annealing

Magnetic field annealing-induced grain refinement usually occurs during the crystallization process of amorphous alloys. This work investigates the effects of magnetic field annealing on the microstructure and magnetic properties of crystalline Ce17Fe76Co1Zr0.5B6Mo0.5 alloys. The results indicate that magnetic field annealing below the Curie temperature (TC) of the Ce2Fe14B phase in the alloys reduces the alloy’s grain size. At an annealing temperature of 433 K, the average grain size of alloys decreased from 48.0 nm in the as-spun sample to 27.2 nm in the magnetic field annealing sample. Moreover, magnetic field annealing can effectively reduce the volume fraction of the CeFe2 phase in the alloy. After magnetic field annealing at 433 K, the alloy obtained the optimal comprehensive magnetic properties: the intrinsic coercivity (Hci = 441.1 kA/m), remanence (Br = 0.49 T), squareness (Hk/Hci = 0.53), and maximum energy product ((BH)max) = 35.5 kJ/m3), which were 0.2 %, 16.7 %, 6 %, and 29.1 % higher than the values of the as-spun sample, respectively. Precession electron diffraction (PED) analysis revealed that magnetic field annealing increased strain at grain and phase boundaries and a more uniform grain orientation spread (GOS), promoting recrystallization and grain refinement. This study provides new insights into the grain refinement mechanism of crystalline alloys under magnetic field annealing, contributing to further improving the magnetic properties of Ce-Fe-B magnets.

High-throughput screening of halide solid-state electrolytes for all-solid-state Li-ion batteries through structural descriptor

All-solid-state Li-ion batteries (ASSLIBs) have attracted great attention due to their intrinsic safety and high potential energy density. To realize ASSLIBs, the development of solid-state electrolytes (SSEs) with favorable electrochemical stability and high Li-ion conductivity is of utmost significance. Compared to trial-and-error searches, theoretical computation-based methods are recognized as a powerful tool for accelerating the exploration of SSEs. However, the development of appropriate descriptors is often the first hurdle toward implementing accurate and meaningful screening process. Here we quantified the structural properties pertaining to low Li-ion migration barriers and performed a high-throughput screening of 3119 Li-containing halides obtained from the Materials Project (MP) database to search for promising SSEs. After excluding previously reported SSEs, three candidate materials, Li4ZrF8, Li3ErBr6, and Li2ZnI4 with crystal structure exhibiting 3D diffusion pathway were obtained. Subsequent theoretical calculations of these materials were performed to evaluate their thermodynamic stability, chemical/electrochemical stability, and ionic conductivity. The three halide materials appeared to be promising SSE candidates due to their robust thermodynamical stability against cathodes, and high ionic conductivity. This research provides a new insight and a systematic quantitative understanding of the relationship between the structural properties and Li-ion migration barriers, which can motivate future computational studies on new fast-ion conductors and accelerate the discovery of high ionic conductivity SSEs for the use in ASSLIBs.

Forging 1,1'-Bicyclopropenyls by Synergistic Au/Ag Dual-Catalyzed Cyclopropenyl Cross-Coupling.

1,1'-Bicyclopropenyl is a constitutional isomer of benzene comprising two coupled cyclopropene units with the endocyclic double bonds in conjugation. Due to the intrinsic high strain energy, it remains a long-standing challenge to prepare 1,1'-bicyclopropenyl derivatives, particularly multisubstituted, nonsymmetrical ones, in an efficient and modular manner. Herein a straightforward Au/Ag bimetallic-catalyzed cyclopropenyl cross-coupling has been developed, providing a robust and versatile strategy for the rapid assembly of symmetrical and unsymmetrical 1,1'-bicyclopropenyl derivatives from cyclopropenyl benziodoxoles (CpBXs) and terminal cyclopropenes. Advantages of this strategy include tolerance to a wide range of synthetically useful functional groups, mild reaction conditions, and a simple catalytic system. The obtained 1,1'-bicyclopropenyl derivatives were shown to be valuable synthetic intermediates through selective downstream manipulations.

Performance evaluation of an inorganic optical fibre dosimeter for use in external beam radiotherapy with pulsed beams

Objective. Optical fibre dosimeters (OFDs) offer great promise for real-timein vivodose measurement in radiation-based treatment modalities such as radiotherapy and brachytherapy. This is attributed to their many useful qualities such as high spatial resolution and sensitivity. However, there are several requirements that an optical fibre dosimeter must meet to be acceptable for dose measurement in a specified treatment modality. In this work, the dosimetric performance of a novel optical fibre dosimeter for use in external beam radiotherapy is presented.Approach. The dosimeter was characterised for photon beam energies between 6-15 MV using a Varian TrueBeam Linac at dose rates between 100-2400 MU/min and assessed based on its repeatability, dose dependence, dose rate dependence, energy dependence and dose-per-pulse dependence.Main Results. The results demonstrated excellent short-term repeatability of 0.3%, good linearity in response (R2>0.9997), and minor dose rate dependence between 0.53%-2.49% for all beam qualities investigated. As the scintillator of the OFD is non-water equivalent, Monte-Carlo-TOPAS simulations were used to calculate the absorbed dose energy dependence. A dose-per-pulse dependence was also investigated and compared with dosimetry measurements made with an ionisation chamber and simulated from the treatment planning system. An over-response of 20%was found at the lowest investigated dose-per-pulse, and an under-response of 34%was found at the highest investigated dose-per-pulse. This is believed to be due to an intrinsic energy dependence making this type of OFD unsuitable for external beam radiotherapy dosimetry.Significance. The OFD evaluated in this work was primarily designed for high-dose-rate brachytherapy whereas this study includes the first measurements made in external beam radiotherapy and highlights the challenges of transferability of the dosimeter to a different radiation source.

A Versatile InF3 Substituted Argyrodite Sulfide Electrolyte Toward Ultrathin Films for All‐Solid‐State Lithium Batteries

AbstractAll‐solid‐state lithium batteries (ASSLBs) incorporating sulfide solid electrolytes capture great attention due to their intrinsic safety features and high energy density. Nevertheless, the implementation of sulfide solid electrolytes faces significant challenges, including moisture sensitivity, narrow intrinsic electrochemical windows, and excessively thick solid electrolyte layers. Here, the substitution of In for P and F for Cl in argyrodite sulfide Li5.7PS4.7Cl1.3 is presented. With appropriate elemental substitutions, the Li symmetric cells exhibit a high critical current density value of 2.5 mA cm−2 and deliver prolonged plating/stripping over 1000 h at 1 mA cm−2 and 25 °C. Further, the Li5.82P0.94In0.06S4.7Cl1.12F0.18 displays high chemical stability toward organic solvents, which is further demonstrated by the density functional theory (DFT) calculations. Using polyisobutylene as a binder, a uniform sulfide film (35 µm) is prepared by slurry casting and hot pressing process, delivering a high ionic conductivity of 1.4 mS cm−1 at 25 °C. Coupled with FeS2 and LiCoO2 cathode, the all‐solid‐state lithium metal cell exhibits a long cycling life and excellent rate performance. This study provides a design strategy and reveals the importance of high‐performance sulfide SEs in the scalable production of sulfide film.

Dynamic tunable nonreciprocal single-photon scattering mediated by a giant atom assisted with a time-modulated cavity

Nonreciprocal single-photon scattering in a one-dimensional waveguide coupled to a giant two-level atom assisted with a time-modulated single-mode cavity is investigated. The analytic expressions of the single-photon scattering amplitudes are derived by using an effective Floquet Hamiltonian in real space. The scattering characteristics are discussed detail in both the Markovian and the non-Markovian regimes, and the corresponding conditions for achieving perfect nonreciprocal single-photon transmission are obtained. In the Markovian regime, a frequency-tunable single-photon diode with an ideal transmission contrast ratio can be realized by adjusting the frequency of the cavity mode, the local coupling phase difference, and the accumulated phase between the two coupling points. Furthermore, the influence of the intrinsic energy dissipations on the photon transport is discussed in detail. It is found that the dissipations of the cavity and the giant atom affect discriminatively the nonreciprocal single-photon scattering process. In the non-Markovian regime, the influence of the non-Markovian retarded effect induced by the time delay on the nonreciprocal single-photon scattering is discussed in detail. The results reveal that, although the retarded effect leads to a complex nonreciprocal scattering spectrum, dynamic tunable perfect nonreciprocal transmission with more abundant physical phenomena suitable for photons with different frequencies within a larger range can also be achieved. Such a nonreciprocal single-photon device can be used as an elementary unit for various quantum information processing and may have potential applications in quantum network engineering.

Resolving the Role of Configurational Entropy in the Optimization of Mechanical, Thermal, and Microwave Dielectric Properties of SrLa(Al0.50-xGaxZn0.125Mg0.125Ti0.25)O4 Ceramics.

The demand for high-performance microwave dielectric ceramics has surged with the proliferation of fifth-generation (5G) communication networks. In this work, SrLa(Al0.50-xGaxZn0.125Mg0.125Ti0.25)O4 (x = 0-0.20) ceramics were designed by leveraging the unique properties of SrLaAlO4 ceramics and high-entropy engineering. The effects of configurational entropy (Sconf = 1.23R - 1.54R) on the mechanical, thermal, and microwave dielectric properties of SrLa(Al0.50-xGaxZn0.125Mg0.125Ti0.25)O4 ceramics were investigated. X-ray diffractometer and transmission electron microscope analyses confirmed that each composition belonged to the tetragonal structure with a space group of I4/mmm. Significant improvements in Vickers hardness were observed with increasing Sconf, reaching 8.05 GPa at Sconf = 1.54R compared to 5.64 GPa in SrLaAlO4 ceramics. Additionally, the increasing entropy showed great potential in reducing the thermal expansion coefficient (CTE) from 12.32 to 11.49 ppm/°C. The optimal quality factor (Q × f) of 98,000 GHz was achieved at Sconf = 1.37R, attributed to the optimization of intrinsic lattice energy and infrared-damped modes. The temperature coefficient of resonant frequency (τf) was successfully modified toward zero due to entropy-driven CTE and structural modifications. Excellent microwave dielectric properties with εr = 22.5, Q × f = 98,000 GHz, and τf = -2.0 ppm/°C were obtained at Sconf = 1.37R. This work highlights the potential of entropy-engineering in developing high-performance microwave dielectric ceramics, offering a promising pathway for the advancement of 5G communication components.

Exploring stacking fault energy with the axial Ising model: A renewed approach

In this work we revisit the axial Ising model for computing intrinsic stacking fault energies (γISF), which are important in alloy design. We find that the supercell approach, which directly compares the energies of fcc stacking with and without a fault, is a specific solution of the Ising model and is the most elegant and efficient among the solutions of the same order of accuracy. Contrary to the traditional belief that only the supercell approach can capture the effect of local chemistry, we demonstrate that local chemistry also influences γISF in the axial Ising model. We also propose a new formula γISF=5EABABC−5EABC, which is similarly efficient, simpler, and more accurate compared to the widely used γISF=EAB+2EABAC−3EABC. We tested the new formula on pure Ni, Ni-Co alloys, and Cr-Mn-Fe-Co-Ni high entropy alloys and found satisfactory results.

Effects of grain size and stacking fault energy on twinning stresses of single-phase CrxMn20Fe20Co20Ni40-x high-entropy alloys

Deformation twinning was investigated in single-phase face-centered-cubic (FCC) high-entropy alloys of the CrxMn20Fe20Co20Ni40-x system (14 ≤ x ≤ 26 at.%). The intrinsic stacking fault energies (γisf) of these alloys varied systematically across this composition range, but other physical properties that have the potential of affecting deformation twinning remained constant allowing us to isolate the effects of γisf on twinning. Tensile tests were performed at 293 and 77 K, and the tests interrupted at several different strains to evaluate deformation-induced changes in microstructure by transmission electron microscopy. The critical stress above which deformation twinning occurs was thus determined. We also evaluated how grain size (19 ≤ d ≤ 237 µm) affects the yield stress (σy) and the uniaxial critical twinning stress (σtw), which allowed us to subtract the corresponding Hall-Petch contributions and compare our polycrystalline results with experimental and theoretical data reported for single crystals. Taking into account the critical resolved shear stresses for deformation twinning in our alloys (τtw) along with those of FCC pure metals and binary alloys reported in the literature, we derived the following relationship that rationalizes most of the experimental data: τtw = 10-3G + γisf/(3·bp), where G is the shear modulus and bp is the magnitude of the Burgers vector of a Shockley partial dislocation. This expression, involving only measurable material properties, can serve as a basis for the design and optimization of new HEAs with tunable twinning stresses and, in turn, exceptional strength-ductility combinations.

On the measurement of piezoelectric d33 coefficient of soft thin films under weak mechanical loads: A rapid and affordable method

Thanks to their intrinsic flexibility, energy efficiency and high portability, soft piezoelectric thin films represent the most effective technological approach for wearable devices to monitor health conditions. In order to improve effectiveness and applicability, more and more innovative and high-performing soft piezoelectric materials are being developed and benchmarked through their piezoelectric d33 coefficient. However, most existing methods to measure the d33 were developed for ceramic or bulk materials and cannot be applied to soft materials because high force/pressure can deform and damage the material structure. This work introduces a simple, effective, and fast method to accurately measure the d33 of soft and thin piezoelectric films by applying weak sinusoidal forces to avoid any damage to the sample, and simultaneously measuring the charges produced by the direct piezoelectric effect. The approach is versatile as it can be used for different types of materials and sizes of the active area. This method represents an effective solution to speed up the process of material optimization, paving the way for the rapid development of novel wearable piezoelectric devices.

Fracture behavior of brittle particulate composites consisting of a glass matrix and glass or ceramic particles with elastic property mismatch

The aim of this work is two-fold: i) elaborating dense and transparent inorganic glass composites with improved fracture properties, and ii) testing the theoretical analysis proposed in [1] and based on Poisson's ratio mismatch. Particulate composites, consisting of glass or ceramic particles embedded in a soda-lime-silica glass matrix, were synthesized and their fracture behavior was studied by means of the Single Edge Precraked Beam (SEPB) and Double Cantilever Drilled (DCDC) methods, using in situ experiments with X-ray tomography where possible. An important effect of the T-stress on the fracture toughness (KIc) was observed in the case of DCDC exdperiments. KIc is increased by about 40 % by incorporating 7 vol. % amorphous silica beads or SrAl2O4:Eu,Dy ceramic particles (SAED) with a 40 μm mean particle size. It is suggested that toughening results from the crack front trapping and pinning at particle sites and from the tortuous crack path in the case of a-SiO2 particles, and from the contribution of the intrinsic fracture surface energy of the ceramic particles, which are cleaved by the propagating crack, in the case of the SAED particles. The thermally induced stress field is believed to play a major role in the case of a-SiO2 particles. Two glass grades possessing Young's moduli similar to the one of the matrix but much larger Poisson's ratios were used to produce glass beads. However, the incorporation of these latter beads in the matrix was found to have a minor incidence on the fracture behavior.

Effects of N, O, S on generalized stacking fault energies and dislocation movements in γ-Ni and γ′-Ni3Al

The effects of interstitial atoms (N, O and S) on generalized stacking fault energies in the γ-Ni and γ′-Ni3Al with were systematically elucidated by first-principles calculations. N, O and S atoms had the preference for octahedral interstitial sites in γ phase. N and S atoms had the preference for octahedral interstitial sites with 6Ni atoms in γ′ phase, while O atom had the preference for octahedral interstitial sites with 2Al4Ni atoms. With the adopted atoms, the intrinsic stacking fault energy in γ phase was decreased and the anti-phase boundary energy in γ′ phase was increased, which were attributed to the charge redistribution between the adopted atoms and neighbouring Ni atoms. The addition of N, S, especially O, hindered the extended dislocation movement and enhanced its formation probability. The addition of O and S atoms significantly enhanced the formation probability of Kear-Wilsdorf dislocation lock in γ′ phase, while the addition of N slightly reduced it.

How do morphological characteristics affect tidal asymmetry in the Radial Sand Ridges?

While it is widely recognized that the Radial Sand Ridges (RSR) in the South Yellow Sea are predominantly shaped by tidal forces, there remains a limited understanding of how this distinctive morphological configuration—characterized by an interlaced channel-ridge system—can subsequently influence local tidal dynamics. This study examines the effects of morphological features on tidal asymmetry, taking into account seabed slope, relative depths between ridges and channels, and channel convergence. Three principal indices—namely tidal-duration-asymmetry (TDA), peak-current-asymmetry (PCA), and slack-water-asymmetry (SWA)—are employed to quantify various dimensions of tidal asymmetry. The findings indicate that SWA serves as the most morphology-sensitive indicator, whereas TDA exhibits minimal sensitivity to morphological changes. Furthermore, seabed steepness emerges as a critical factor influencing tidal asymmetry within the RSR; steeper slopes enhance intrinsic energy conversion processes, thereby inducing tidal asymmetries. Additional analysis reveals that streamwise advection accounts for an average of 88 % of total advection scale while controlling for spatial heterogeneity. Specifically, the average integral sum of advection terms along submerged sand ridges is 2.53 times greater than that along the deepest section of the tidal channel line—a significant contributor to spatial variability in SWA. With a positive seabed slope, the apex of the RSR acts as a source for overtides which interact with incoming astronomical tides, consequently generating tidal asymmetries. Moreover, this study illustrates varying dependencies of tidal asymmetry on bottom stress across channels and ridges, contributing to spatial variability in arc direction among RSRs. Ultimately, this research elucidates complex interactions between tidal flow and morphological characteristics within RSRs and provides insights into tide evolution in analogous ebb-shoal systems.

The role of crystallographic orientation on surface properties and ion transport in lithium germanate (Li2GeO3) anodes: A computational approach

The performance of lithium-ion batteries (LIBs) hinges on the surface properties of their anodes. Compared to the bulk material, the anode surface is more susceptible to environmental changes during lithium (Li) intake and release, directly impacting factors like capacity, cycling stability, and charge/discharge rates. Lithium germanate (Li2GeO3, LGO) has emerged as a promising anode material due to its fast Li-ion conduction. While numerous studies have explored performance improvements through various methods, including defect engineering. However, there is currently a lack of atomistic-level understanding of the surface structure. Consequently, despite the importance of precisely understanding the surface to manipulate its different properties, specific surface details of LGO remain unclear. This knowledge gap hinders precise manipulation of surface properties for optimal performance.This study addresses this critical need by employing theoretical calculations to predict the structural, electrochemical characteristics, and Li-ion transport behavior in LGO surfaces. Our results indicate that polar surfaces exhibit lower formation energies compared to non-polar surfaces. Further investigation revealed that Li-terminated surfaces possess the lowest surface energy among various surface terminations. Interestingly, the work function calculations displayed an opposite trend to surface formation energy, with polar surfaces exhibiting the lowest work function values.To explore Li-ion transport, we employed ab initio molecular dynamics simulations. Notably, the (003) surface displayed the highest Li-ion diffusion rate among all considered surfaces.Further analysis of the (001) surface, which exhibited similar diffusion pathways to the (003) surface, revealed a lower diffusion rate.To understand this disparity, nudged elastic band (NEB) simulations were used to estimate the energy barriers for Li-ion migration along each pathway in both structures. Despite sharing similar pathways, the energy barriers in the (003) surface were significantly lower than those in the (001) surface. This finding suggests that the intrinsic energy landscape of the surface plays a crucial role in dictating Li-ion transport behavior.

Electrochemical Nitrogen Reduction: The Energetic Distance to Lithium.

Energy-efficient electrochemical reduction of nitrogen to ammonia could help in mitigating climate change. Today, only Li- and recently Ca-mediated systems can perform the reaction. These materials have a large intrinsic energy loss due to the need to electroplate the metal. In this work, we present a series of calculated energetics, formation energies, and binding energies as fundamental features to calculate the energetic distance between Li and Ca and potential new electrochemical nitrogen reduction systems. The featured energetic distance increases with the standard potential. However, dimensionality reduction using principal component analysis provides an encouraging picture; Li and Ca are not exceptional in this feature space, and other materials should be able to carry out the reaction. However, it becomes more challenging the more positive the plating potential is.

Coherence resonance in a memristive map neuron and adaptive energy regulation

Involvement of memristive term and additive physical variables including magnetic flux and charge can enhance the physical description of the biophysical neurons. Neural circuits coupled with memristors can be built and tamed to mimic the intrinsic biophysical characteristics and dynamical properties of biological neurons, and these memristive oscillator models are effective in predicting the mode transition in neural activities and self-organization in collective electric behaviors of neural networks. Any proposal of memristive map neurons requires reliable physical description. For example, the energy definition and self-adaptive working mechanism are crucial to verify the reliability of memristive maps. A capacitive variable is useful to describe the membrane potential, while the complexity of ion channels requires careful evaluation and description by using inductive variables relative to the electromagnetic field. In this work, a charge-controlled memristor is connected to an inductor in series for building a hybrid ion channel, and then a capacitor and a nonlinear resistor are combined to couple the ion channel. As a result, a simple memristive neural circuit is designed to discern the inner effect of electric field and magnetic field synchronously. The energy function is defined and verified with theoretical proof. Furthermore, a linear transformation is applied to convert this memristive neuron into a memristive map with an exact energy description, in which its dynamics and mode transition will be controlled by an adaptive law when its energy is beyond the threshold. Additive noise is imposed to induce coherence resonance, which can be detected by using the statistical analysis and average value for Hamilton energy function during changes in noise intensity. This scheme provides guidance for energy definition in memristive maps and the intrinsic energy regulation mechanism in neural activities is explained from physical and dynamical aspects.