SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4482-6
Polymer semiconductors offer solution processability, mechanical flexibility, and molecular tunability for flexible displays, wearable devices, and the Internet of Things, yet their charge transport properties remain substantially inferior to inorganic semiconductors. Efficient charge transport demands simultaneous structural order across molecular conformation, aggregate connectivity, and macroscopic orientation, but these length scales are strongly coupled: primary aggregates in solution, secondary nucleation during solvent evaporation, and final film solidification intertwine, rendering structural control dependent on empirical trial and error. Prior approaches—molecular design, solvent additives, thermal annealing, and shear coating—have improved crystallization and orientation, but two interrelated issues persist. First, enhancing aggregation does not guarantee higher mobility: insufficient aggregation yields small, loosely connected structures, while excessive aggregation causes premature nucleation, fiber twisting, and large grain boundaries. Second, direct observation of how solution aggregates evolve across molecular, mesoscopic, and macroscopic scales into solid films is often lacking. The fundamental challenge is not whether to promote crystallization, but how to cooperatively control aggregate type/size, internal order, connectivity, and assembly pathway, and to transform empirical solvent selection into predictive design rules. Zhao et al. report a self-templated gradient assembly (STGA) strategy that couples solubility parameters with vapor pressure to regulate both solution-state aggregation and assembly kinetics. Unlike conventional anti-solvent approaches that trigger rapid nucleation, STGA operates within mutually compatible solvent mixtures that retain polymer solubility and generate a continuous decline in solvent quality during evaporation. Preformed ordered aggregates become endogenous templates for subsequent assembly and crystallization rather than transient intermediates. Using a newly designed linear donor–acceptor polymer, PFIDTO-BT, and the relative energy difference (RED) index, cryogenic transmission electron microscopy confirmed that primary aggregates systematically enlarge as solvent quality decreases. Vapor pressure provides a second dimension, defining a solvent-selection matrix. For low-solubility, low-volatility components, the selectivity toward side chain/backbone parameter Ratio (S/B) further distinguishes aggregation pathways induced by different poor solvents. This framework connects solvent selection to hierarchical polymer organization through a semi-quantitative, experimentally testable methodology, enabling single-crystal-like polymer semiconductors with ultrahigh charge carrier mobility.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3739-8
The premature decay of electrochemical nitrogen reduction reaction (eNRR) performance at low electrode potentials remains a major obstacle to practical applications, primarily due to competition from the hydrogen evolution reaction (HER). A new paradigm capable of transcending current selectivity constraints is urgently required to advance eNRR toward industrial implementation. In this work, we propose two practical selectivity descriptors (ΔΔG and ΔU) based on a systematic investigation of the potential-dependent competition between eNRR and HER on confined dual-atom catalysts. The descriptor ΔΔG (ΔG_N2 − ΔG_H) identifies the potential range where N2 adsorption dominates over H adsorption, while ΔU (U_cross – U_eNRR) specifies the potential range to trigger direct eNRR, offering a quantitative benchmark for rational catalyst design. Ideal catalysts should maintain N2-preferential adsorption across a broad potential window to facilitate direct eNRR. Guided by this insight, we demonstrate that confined dual-atom configurations with optimized interatomic distances can simultaneously achieve both overwhelming N2 adsorption and sufficient activation, thereby overcoming conventional selectivity limitations. This strategy enables ammonia synthesis with industrially relevant production rates and current density even at elevated potentials. Our mechanistic insights not only elucidate the root causes of performance limitations in eNRR but also offer a rational design framework for developing high-performance catalysts across a broad range of electrochemical transformations.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202506019
Acidic in-situ leaching of sandstone-type uranium deposits leaves residual acid and uranium in groundwater, posing environmental risks. This study investigated the feasibility of loading hydroxyapatite (HAP) onto aquifer sandstone particles for in-situ remediation. Sandstone particles were collected from an aquifer and reacted with a HAP-generating solution for 52 days to produce sandstone/HAP composite. Batch experiments examined the effects of initial pH, initial uranium concentration, composite dosage, and interfering ions on uranium removal. Results showed successful HAP loading on sandstone surfaces. At initial pH 3, uranium concentration 5 mg/L, composite dosage 3 g/L, and 24 h reaction, uranium removal reached 95.6%. Interfering ions suppressed removal in the order Fe3+ > Mn2+ > Ca2+ > Mg2+ > SO4^2-. Removal mechanisms included electrostatic adsorption, ion exchange, and dissolution-reprecipitation, with good stability of immobilized uranium. This work validates the concept of in-situ HAP loading in aquifers and provides a basis for practical application in acidic uranium-contaminated groundwater remediation.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202606012
River and lake sediments, as both sources and sinks of water pollutants, significantly impact overlying water quality and aquatic ecosystems. In pollution treatment and ecological restoration, managing contaminated sediments is critical. Remediation technologies are categorized into ex-situ and in-situ methods; in-situ techniques have gained prominence due to lower costs and minimal environmental disturbance. This review summarizes sediment pollution status, comprehensively examines physical, chemical, biological, and combined in-situ remediation technologies, and discusses their mechanisms, applications, and future research needs. It proposes optimization strategies for emerging technologies, material improvements, and pathways for sustainable development, emphasizing interdisciplinary integration to enhance remediation efficacy. Key pollutants include heavy metals (e.g., Cd, Hg), persistent organic pollutants (POPs), and emerging contaminants like antibiotics and microplastics. In-situ methods such as capping, chemical oxidation, and bioremediation show promise but face challenges in long-term stability and scalability. The paper underscores the need for sustainable, cost-effective solutions and highlights recent advances in combined technologies, offering a reference for future research and engineering applications.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3994-9
Electrokinetics, the study of charge transfer and mass transport under electric fields, is fundamental to advancing energy storage and electrocatalysis. Organic-inorganic composite materials synergistically combine the structural stability and conductivity of inorganic phases with the functional diversity of organic components, optimizing electrokinetic properties such as charge transfer, ionic mobility, and catalytic activity. This review systematically examines the intersection of electrokinetic phenomena and organic-inorganic composites, focusing on fundamental principles, design strategies, and performance optimization. Advanced materials including metal-organic frameworks (MOFs), organic-carbon hybrids, and single-atom catalysts are highlighted, with applications spanning batteries, fuel cells, wearable devices, and electrocatalytic systems. Emphasis is placed on advanced in situ and operando characterization techniques that probe electrokinetic processes, revealing the interplay between structure, interface, and transport dynamics. By bridging electrokinetic theory and material design, this work provides a roadmap for developing next-generation materials for sustainable energy technologies. The review consolidates recent progress, identifies remaining challenges, and proposes future directions for leveraging electrokinetic principles to achieve high-efficiency, durable energy systems.