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Verified CAS / Academic Author5 Decoded Studies

Prof. ZHENG Zhi

School of Materials Science and Engineering, North University of China, Taiyuan 030051, China; Shanxi Key Laboratory of Efficient Hydrogen Storage & Production Technology and Application, North University of China, Taiyuan 030051, China

Co-Affiliations:School of Environment and Ecology, Jiangnan University, Wuxi 214122, ChinaXizang University / Guangzhou Institute of Energy Conversion, Chinese Academy of SciencesBeijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China

Research Publications & English Decoded Briefs

Showing 5 publications
New Carbon Materials2026DOI: 10.1016/S1872-5805(26)61071-2

Boron and Nitrogen Co-Doped Coal-Based Activated Carbon as Cathode Material for High-Performance Aqueous Zinc-Ion Hybrid Capacitors

Aqueous zinc-ion capacitors (ZICs) are promising energy storage systems due to their high specific capacity and superior reliability. Heteroatom-doped carbon materials have been shown to substantially increase the capacitance of ZICs, yet the underlying mechanisms remain poorly understood. In this work, coal-based activated carbon was functionalized with both boron (B) and nitrogen (N) to serve as the cathode material in ZICs. The optimized material, designated CAC-120, exhibits a high specific capacity of 371.4 mAh g−1 at 1 A g−1 and retains 74% of its initial capacity after 10,000 cycles. Electrochemical analysis and density functional theory (DFT) calculations reveal that pyridinic N plays a crucial role in enhancing Zn2+ storage, demonstrating superior electrochemical reversibility. Furthermore, an assembled aqueous ZIC using the CAC-120 cathode achieves a high reversible capacity of 90.8 mAh g−1 at 0.2 A g−1 and exceptional long-term stability over 17,000 cycles. This work provides valuable insight into the design of high-capacity and ultrafast pseudocapacitive carbon cathodes for ZICs, highlighting the synergistic effects of pore structure engineering and heteroatom doping.

Chinese Journal of Environmental Engineering2026DOI: 10.12030/j.cjee.202506031

Preparation and Engineering Scale-Up of Cyanobacteria-Based Columnar Activated Carbon

The production of activated carbon from waste biomass such as cyanobacteria from Lake Taihu represents a promising resource utilization route. However, existing studies are mostly confined to laboratory scale, and the gap between laboratory processes and industrial production hinders the evaluation of technical feasibility and economic viability. This study optimized the process for producing cyanobacteria-based columnar activated carbon by co-processing cyanobacteria with garden waste (sawdust), and validated the process on an engineering-scale production line with a daily capacity of 5 t of raw materials. Economic feasibility was also assessed. Results showed that the optimized activated carbon exhibited a particle strength of 91.3% and a specific surface area of 571.44 m2·g−1. The engineering-scale line processed 5 t of raw materials daily, yielding approximately 1.18 t of activated carbon with stable quality: strength of 94.3% and specific surface area of 471.42 m2·g−1, featuring a microporous-dominant structure with coexisting micropores and mesopores. Cost analysis indicated a production cost of 3,595.65 CNY per ton of activated carbon, demonstrating favorable economic benefits. This work provides a basis for larger-scale production and application of cyanobacteria-based activated carbon.

SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3790-5

Defect and Crystal Field Engineering Enables High Efficiency and Anti-Thermal Quenching in Cr3+ Doped Rigid Garnet Phosphors for Multifunctional Optoelectronics

Near-infrared (NIR) phosphors with high quantum efficiency (QE) and thermal robustness are critical for phosphor-converted light-emitting diodes (pc-LEDs). Here, a Cr3+-activated Lu2BaAl4SiO12 (LBASO) garnet phosphor is engineered via chemical unit cosubstitution of [Ba2+-Si4+] for [Lu3+-Al3+] in Lu3Al5O12 (LuAG), inducing a strong crystal field that yields NIR emission at 705 nm. The optimized LBASO:0.07Cr3+ exhibits an internal quantum efficiency (IQE) of 84.82% and external quantum efficiency (EQE) of 46.02%. Notably, it demonstrates anti-thermal quenching (ATQ) with 126.03% of its initial intensity at 498 K under 442 nm excitation, attributed to a wide band gap, weak electron-phonon coupling, defect trap energy levels, high structural rigidity, and optimized electron population distribution. A NIR pc-LED fabricated with this phosphor achieves an output power of 134.99 mW and photoelectric conversion efficiency of 11.4% at 100 mA drive current. These results underscore the potential of LBASO:Cr3+ for applications in plant lighting, night vision, and nondestructive analysis.

Journal of Environmental Engineering Technology2026DOI: 10.13205/j.hjgc.202607016

Preparation of Biochar from Co-pyrolysis of Napier Grass and Food Waste Digestate for Pb²⁺ Removal from Wastewater

Lead (Pb) is a highly toxic heavy metal that poses severe risks to environmental and human health, particularly affecting children's neurological development. This study investigates the adsorption performance and mechanisms of biochars derived from pyrolysis of Napier grass (Pennisetum purpureum), food waste digestate, and their mixtures for Pb²⁺ removal from aqueous solutions. Biochars were prepared at different mass ratios, and the optimal material (HP3SD1-B, Napier grass:digestate = 3:1) exhibited a maximum equilibrium adsorption capacity of 306.45 mg/g and a theoretical Langmuir maximum capacity of 447.62 mg/g, significantly outperforming pure digestate biochar and lower-ratio blends. Adsorption kinetics followed a three-stage profile: rapid liquid-film diffusion (0–180 min), intraparticle diffusion (180–360 min), and equilibrium at 360 min. The adsorption process was well described by the pseudo-second-order kinetic model (R² > 0.99) and the Langmuir isotherm, indicating monolayer chemisorption. Characterization via FTIR, XPS, SEM-EDS, and Zeta potential revealed that Pb²⁺ immobilization occurs primarily through surface precipitation (Pb₃(CO₃)₂(OH)₂ and PbO), complexation with hydroxyl, ether, and aromatic C=C groups, and auxiliary mechanisms including electrostatic attraction and K⁺/Mg²⁺ ion exchange. Optimal adsorption occurred at pH 6, correlating with the point of zero charge (PZC ≈ 2). This study demonstrates that co-pyrolysis of agricultural and organic solid wastes offers a cost-effective, high-performance biochar for heavy metal remediation, aligning with circular economy principles.

SCIENCE CHINA Materials2025DOI: 10.1007/s40843-025-3366-9

Organic Solar Cells Surpassing 20% Power Conversion Efficiency: Material Innovations, Device Engineering, and Pathways to Flexible Power Suppliers

Organic solar cells (OSCs) have transitioned from <1% initial power conversion efficiency (PCE) to a benchmark exceeding 20% in single-junction and tandem architectures, marking a critical milestone for solution-processable photovoltaics. This review consolidates recent reports (2022–2025) on OSCs with PCE >20%, analyzing key strategies: photoactive material innovation (wide-bandgap polymer donors, narrow-bandgap non-fullerene acceptors), multi-component system construction, deposition protocol optimization, solid/solvent additive engineering, and hole/electron transport layer development. Empirical data from 15 high-impact studies reveal PCEs of 20.0–20.6% in single-junction devices and 20.2–26% in perovskite/organic tandem cells, with interfacial engineering (e.g., yttrium phosphotungstate, carbazole-modified 2PACz, naphthalene diimide interlayers) suppressing bimolecular recombination and enabling scalable large-area fabrication. Operational stability remains a bottleneck: amide-based cathode interlayers achieve 20% PCE with dual-modification mechanisms, while self-assembled monolayers enable hole transport layer-free devices with 18% efficiency and improved stability. The review identifies next-stage challenges: reducing voltage losses (to <0.5 V), scaling deposition uniformity beyond 100 cm², and achieving cost parity with silicon (<$0.30/Wp). These issues are critical for flexible and wearable power suppliers, where mechanical durability (<5% PCE degradation after 1000 bending cycles) and low-temperature processing (<150°C) are mandatory. The analysis provides a roadmap for industrial translation, emphasizing that material–device co-optimization, rather than isolated breakthroughs, will determine commercial viability.