Joule最新文献

High-entropy engineering effectively reduces lattice thermal conductivity (κ_L) in thermoelectric (TE) materials; however, the chemical complexity of multiple elements in high-entropy materials often leads to phase segregation, limiting their electrical transport properties and overall TE performance. Herein, we report a p-type high-entropy stabilized single-phase half-Heusler alloy, MFeSb, specifically designed to enhance configurational entropy by introducing multiple element species on a single atomic site. This material exhibited low κ_L due to phonon group velocity reduction and strong phonon scattering from lattice strain generated through distorted lattices while maintaining a high power factor. The material demonstrated a record high figure of merit (zT) of 1.5 at 1,060 K, with an average zT of ∼0.92 over 300–1,060 K. Furthermore, superior conversion efficiencies of 15% and 14% for a single-leg and a unicouple module at a temperature difference of ΔT ∼671 K were achieved. Our findings provide a new avenue for enhancing TE material performance through high-entropy engineering.

The huge thermopower observed in the thermodiffusion mechanism of ionic thermoelectric (i-TE) materials has led researchers to conceive of the upgrading of thermoelectric technology. However, the intermittent power generation in the capacitor mode has been a major hindrance to achieving optimal performance. This work proposes a conveyor mode for continuous i-TE conversion in mixed ion-electron-conducting i-TE material with an ionic circuit. In this conveyor mode, ion-electronic friction serves as the link between ions and electrons, enabling the thermally diffused ions to convey electrons to power the load, and persistent ionic transport, owing to the ionic circuit, ensures continuous power generation. Experiments demonstrate continuous power generation and significant improvements of power density in the conveyor mode. Theoretical analysis shows that the conveyor mode is competitive to not only the capacitor mode but also a general electronic thermoelectric conversion. Our study points out a direction for the development of i-TE technology.

Residual tensile strain impedes the improvement of efficiency and intrinsic stability of perovskite solar cells (PSCs), resulting from the perovskite lattice distortion and different thermal expansion coefficients. Herein, we propose a molecule-triggered strain regulation and interfacial passivation strategy to enhance the efficiency and stability (especially photostability) of PSCs, which utilizes the [2 + 2] cycloaddition reaction of 6-bromocoumarin-3-carboxylic acid ethyl ester (BAEE), consuming the incident UV light to suppress the tensile strain evolution. Meanwhile, the BAEE can form a strong bond with NiO_x, assisting the perovskite growth and the interface defect passivation. We obtain the efficiency of 26.32% (certified 26.08%), the open-circuit voltage (V_oc) up to 1.201 V with low V_oc loss (0.342 V), as well as the long-term stability (continuous 365 nm UV illumination: T₉₀ > 110 h in N₂, T₉₀ > 6 h in ambient air, and continuous LED white light irradiation at 100 mWcm⁻²: T₉₀ > 1,000 h).

The thermoelectric cyclic-thermal-regulation (TEcR) system was defined as cyclical heat pumping between two vessels in a transient mode, which has emerged as a new application in gas separation and temperature-driven soft robots. Here, we provided systematic theoretical fundamentals relative to the TEcR system and proposed the determining factors and performance scales. We have also designed and fabricated a thermoelectric CO₂-gas-separation system based on low-temperature adsorption and high-temperature desorption, verifying the feasibility of the TEcR system. Our experiments unequivocally demonstrate the significant potential of the TEcR system, with energy consumption savings of 42% and cycle frequency improvements of 2.5 times compared with electrical heater systems. We also proposed an empirical figure of merit to guide the thermoelectric material optimization strategies for the TEcR application. Our work sheds light on the new application of thermoelectric materials, which would generate implications for a wide range of industrial applications that use multi-plate thermal energy.

Formation is a critical step in battery manufacturing. During this process, lithium inventory is consumed to form the solid electrolyte interphase (SEI), which in turn determines the battery lifetime. To tackle the vast parameter space and complexity of formation, we employ a data-driven workflow on 186 lithium-ion battery cells across 62 formation protocols. We identify two key parameters, formation charge current and temperature, that control battery longevity via distinct mechanisms. Surprisingly, high-formation charge current on the first cycle extends battery cycle life by an average of 50%. Unlike elevated formation temperature, which boosts battery performance by forming a robust SEI, the cycle life improvement for fast-formed cells arises from a shifted electrode-specific utilization after formation. Apart from the widely acknowledged role of formation in governing SEI properties, we demonstrate how formation protocols determine the stoichiometry range over which the positive and negative electrodes are cycled.

Additive-assisted layer-by-layer (LBL) deposition affords interpenetrating fibril network active layer morphology with a bulk p-i-n feature and proper vertical segregation in organic solar cells (OSCs). This approach captures the balance between material interaction and crystallization that locks the characteristic length scales at tens of nanometers to suit exciton and carrier diffusion, thereby reducing recombination losses. On the other hand, the wrinkle-pattern morphology generated due to Marangoni-Bénard instability and radial flow during spin-coating couples with the reflective back electrode, inducing diffuse reflection and thus enhancing light capture capability. The nano-to-micron hierarchical morphology in proper vertical segregation achieves a record-breaking power conversion efficiency (PCE) of 20.8% for small-area devices and 17.0% for mini-module devices. The new processing and the resulted 3D morphology better suit photon and carrier dynamics in operation, such that a notable improvement in device operational stability is recorded, which offers a plausible strategy toward practical organic photovoltaic technology.