SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3604-1
Piezoelectric materials convert mechanical energy into electrical signals, enabling applications in sensors, actuators, and energy harvesting. Inorganic ceramics like PZT and BTO exhibit excellent piezoelectric properties but are brittle, limiting their use in flexible electronics. This work presents a porous composite of PZT@carboxymethyl chitosan (CMCS) in thermoplastic polyurethane (TPU). The core-shell structure enhances interfacial compatibility, while the porous TPU skeleton facilitates stress transfer and amplification, allowing high piezoelectric content. The resulting PZT@CMCS/TPU devices achieve an output voltage of 53 V and current of 13 μA, an 11-fold improvement over conventional PZT composite films. This approach enables flexible piezoelectric devices with high performance.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3584-3
Sutures, as necessary medical devices for postoperative treatment, are no longer merely supportive but are required to have advanced functions to promote repair. Here, we report an absorbable self-powered electrical stimulation suture (SES-suture). The suture is composed entirely of absorbable materials (magnesium, polylactic acid, and polycaprolactone) and can be used in vivo for incision closure and repair. The suture has the capacity to generate spontaneous electrical stimulation in response to body movement, allowing for accelerated tissue reconstruction. An in vivo muscle incision repair model in rabbits demonstrated that the wound healing rate under treatment with this suture was 1.6 times faster than that of commercial sutures, proving its postoperative therapeutic capability. Immunofluorescence and quantitative analyses showed that SES-sutures significantly increased α-SMA and CD31 expression, with levels approximately 2.8 and 3.2 times higher than the blank group, respectively, indicating enhanced angiogenesis and muscle regeneration. The SES-suture exhibited excellent mechanical properties, sustained electrical output, structural and functional stability after implantation, and good biocompatibility. This large animal approach offers crucial translational evidence for potential human applications, addressing the limitations of rodent models due to differences in biomechanics and regeneration rates. While the biosafety profile requires further long-term evaluation, the findings strongly suggest that SES-sutures represent a promising therapeutic strategy for enhancing tissue regeneration and functional recovery.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511051
Photosynthetic bacteria (PSB) wastewater treatment technology is promising for simultaneous pollutant removal and resource recovery (e.g., single-cell protein, hydrogen). However, poor cell hydrophobicity and aggregation lead to low biomass retention and short sludge retention time, hindering engineering application. This study investigated the driving role and mechanism of upflow velocity as a key hydraulic selection pressure on PSB granulation under stepwise increasing organic loading rate (OLR). In laboratory up-flow photobioreactors (UPBR), comparative experiments were conducted with macro-index monitoring and micro-mechanism analysis. Results showed that under high upflow velocities of 3.00–6.30 m·h−1, PSB granular sludge with an average diameter of 285.58 μm and excellent settleability (sludge volume index, SVI = 22.73 mL·g−1) was successfully formed within approximately 60 days. Compared to the control, the granules in the experimental group were larger, with clear boundaries and compact structure, and significant enrichment of filamentous bacteria was observed. Mechanism analysis indicated that OLR provided nutritional driving force for microbial growth, while upflow velocity supplied high hydraulic shear force, physically screening and enriching settleable aggregates, and specifically inducing secretion of hydrophobic tryptophan-like proteins and humic acids (key extracellular polymeric substances, EPS). Additionally, core genera such as Xanthobacteraceae, possessing stress tolerance and EPS secretion functions, were enriched. This study reveals a chain mechanism of 'physical selection–biological response' centered on hydraulic selection, demonstrating that upflow velocity is a key controllable factor for PSB granulation, providing theoretical basis and technical pathway for solving PSB biomass washout and promoting resource-oriented treatment of high-strength organic wastewater.