Peng Sun

Flexible graphite packing rings are widely employed in high-temperature and high-pressure valve sealing systems owing to their intrinsic lubricity and thermal stability, yet their service reliability is often compromised by low mechanical strength, pronounced creep, and unstable tribological behavior under extreme conditions. Here, we present an interface-engineered strategy to enhance the service performance of graphite packing rings via reinforcement with surface-functionalized PAN-based carbon fibers (PAN-CFs; carbonized fibers derived from polyacrylonitrile precursors). Through controlled oxidative modification of carbon fibers combined with high-temperature graphite expansion, a three-dimensional reinforced graphite network with uniform fiber dispersion was constructed. The influence of PAN-based carbon fiber (PAN-CF) content (0–7 wt%) on compressive strength, thermal stability, friction behavior, and long-term durability was systematically evaluated. An optimal performance was achieved at 5 wt% PAN-CF, featuring a ~58% increase in compressive strength, a stable friction coefficient of 0.15–0.18, and enhanced creep resistance, while retaining over 78% of the initial strength after 1000 h of sustained loading. Microstructural and complementary structural analyses suggest that these improvements are associated with interfacial mechanical anchoring, fiber embedding, and load-transfer reinforcement enabled by fiber surface functionalization and the expanded graphite architecture. This work offers a practical material-level approach to improving the long-term reliability of graphite-based sealing components in demanding industrial environments.

Efficient Ce ³⁺ → Cr ³⁺ energy transfer overcomes the intrinsically weak absorption of Cr ³⁺ and boosts NIR emission in the CaLu ₂ Mg ₂ Si ₃ O ₁₂ host.

A micro-etching method is used to enhance tensile strength and reduce the contact resistance between Bi ₂ Te ₃ -based thermoelectric leg and copper electrode, leading to effective and reliable output performance in thermoelectric power generators.

By introducing the active telluride Ag ₉ GaTe ₆ in p-type Bi _0.4 Sb _1.6 Te ₃ , lath twin boundaries are induced as differential scattering centers for carriers and phonons, leading to improved ZT values and high thermoelectric conversion efficiencies.

By adding “weakly-active” SGPT and Cu, differentiated electro-phonon scattering centers are induced to significantly suppress κ_ph with μ less affected, leading to a ZT_ave of 1.32 and a η of 6.8%.

A Bi ₂ Te ₃ -based thermoelectric device with high thermoelectric performance and flexibility for human body waste heat recovery and temperature management.

The highly active additive Cu₂SnTe₃ generates multi-scale defects, effectively reducing lattice thermal conductivity. Along with optimized weighted mobility, the higher quality factor yields a competitive ZT value in the (Bi,Sb)₂Te₃-based composite.

The thermal-electric conversion efficiency is a crucial metric for evaluating the performance of a thermoelectric generator (TEG). However, accurate measurement of this efficiency remains a significant challenge due to various factors that impact heat flow measurements. We have observed that temperature fluctuations during temperature control are the primary factor contributing to measurement errors in heat flow under vacuum conditions. To address this issue, we have developed a time-dependent theoretical model for the thermal-electric coupling of a TEG measurement system based on Fourier’s theory of heat conduction. This model allows us to investigate the effects of both temperature fluctuation and structural parameters on the measurement error of TEG performance. Furthermore, we have proposed an error correction scheme for TEG performance based on our theoretical and experimental findings. These insights provide a theoretical framework and technical guidance for more precise measurements of TEG performance.

In this study, we have designed and developed an implantable thermoelectric generator (TEG) module tailored for large-scale flue gas waste heat recovery. We also have established a test stand to simulate diverse operational conditions, and systematically examined the influence of different operating conditions, including flue gas temperature, flue gas velocity, and cooling water temperature, on the electrical performance of the TEG module. When the flue gas temperature is 139 °C, the flue gas flow rate is 3.4 m/s, and the cooling water temperature is 20 °C, the TEG module operates at its peak performance. It achieves an open-circuit voltage of 856.3 V and an output power of 150.58 W. Furthermore, the TEG module demonstrates a notable power generation capacity of 3.86 kW/m³ and a waste heat recovery capacity of 135.85 kW/m³. The results prove the TEG module as an effective solution for large-scale flue gas waste heat recovery in industrial settings, contributing to sustainable energy practices. This study supports the application of thermoelectric power generation in the industrial sector, offering significant potential for advancements in energy efficiency.

(Phosphor‐converted white laser diode (PC‐WLD) lighting shows promise for high‐luminance solid‐state illumination. However, luminescence saturation, stemming from optical and thermal factors and, hampers high‐power LD lighting progress. This study delves into the light‐thermal dynamics between lasers and Y₃Al₅O₁₂:Ce³⁺ （YAG:Ce）transparent ceramic phosphors (TCPs). Over 48.9% of absorbed laser power generates heat, inducing luminescence saturation. To effectively handle heat dissipation, we introduce a Luminescence‐Refrigeration Module (LRM) comprising the YAG:0.005Ce³⁺ TCP and a thermoelectric cooler (TEC). The LRM raises laser power density saturation by 4.5 times, meeting high‐power laser lighting requirements. The designed LRM emerges as a groundbreaking strategy for advancing high‐power LD lighting devices.)