SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4351-8
Breaking intrinsic structural symmetry is a fundamental prerequisite for pronounced nonlinear optical responses. Low-symmetry semiconductors with inherent anisotropy enable self-powered optoelectronic conversion and polarization-sensitive functionalities. This work reports the synthesis of low-dimensional van der Waals chain TeSe2 crystals with intrinsic inversion and C3 symmetry breaking. Angle-resolved polarized Raman spectroscopy and second-harmonic generation measurements confirm crystalline anisotropy and nonlinear optical performance. Electrical transport studies reveal p-type conduction with a room-temperature field-effect mobility of 122 cm2 V-1 s-1. The TeSe2 photodetector achieves self-powered detection and linearly polarized light detection across 405–1064 nm, with a photoresponsivity of 77.3 mA/W at 532 nm. The linear photogalvanic effect response is effectively modulated by gate voltage. Density functional theory calculations attribute p-type doping to Te and Se vacancies, while the nonlinear optical origin is linked to strong Berry curvature. Applications in polarization encoding communication and polarization imaging are demonstrated, indicating potential for low-energy-consuming, highly sensitive, on-chip integrated linear polarized photodetectors.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4138-5
Electrocoagulation (EC) has emerged as a promising electrochemical technology for wastewater treatment, offering distinct advantages over conventional chemical coagulation and membrane processes. This review systematically summarizes recent advancements in EC, focusing on the underlying mechanisms, key operating parameters, and diverse technical applications. The EC process involves three stages: electrolytic oxidation and in-situ coagulant formation, destabilization of contaminants, and floc formation. Unlike chemical coagulation, EC requires no external chemical additives, and process control is achieved by adjusting current density, voltage, or electrode materials, enabling adaptation to varying wastewater qualities. The review highlights the influence of dissolved organic matter (DOM) on EC efficiency, as clarified by Luo et al. (Water Research, 2025). Furthermore, it discusses reactor design innovations, including continuous-flow and cascade-type configurations, and the role of current waveforms in mitigating electrode passivation. The integration of EC with membrane bioreactors and forward osmosis is also examined, demonstrating enhanced treatment performance and fouling mitigation. Key challenges, such as energy consumption and electrode scaling, are addressed, along with future research directions. This comprehensive analysis provides a critical framework for optimizing EC systems and scaling them for industrial wastewater treatment, emphasizing the need for holistic reactor design and process integration to achieve sustainable water reuse.