Nano-Micro Letters

Naturally derived nanocellulose with unique physiochemical properties and giant potentials as renewable smart nanomaterials opens up endless novel advanced functional materials for multi-sensing applications. However, integrating inorganic functional two-dimensional carbon materials such as graphene has realized hybrid organic–inorganic nanocomposite materials with precisely tailored properties and multi-sensing abilities. Altogether, the affinity, stability, dispersibility, modification, and functionalization are some of the key merits permitting their synergistic interfacial interactions, which exhibited highly advanced multifunctional hybrid nanocomposites with desirable properties. Moreover, the high performance of such hybrids could be achievable through green and straightforward approaches. In this context, the review covered the most advanced nanocellulose-graphene hybrids, focusing on their synthetization, functionalization, fabrication, and multi-sensing applications. These hybrid films exhibited great potentials as a multifunctional sensing platform for numerous mechanical, environmental, and human bio-signals detections, mimicking, and in-situ monitoring.

Polymer solid-state lithium batteries (SSLB) are regarded as a promising energy storage technology to meet growing demand due to their high energy density and safety. Ion conductivity, interface stability and battery assembly process are still the main challenges to hurdle the commercialization of SSLB. As the main component of SSLB, poly(1,3-dioxolane) (PDOL)-based solid polymer electrolytes polymerized in-situ are becoming a promising candidate solid electrolyte, for their high ion conductivity at room temperature, good battery electrochemical performances, and simple assembly process. This review analyzes opportunities and challenges of PDOL electrolytes toward practical application for polymer SSLB. The focuses include exploring the polymerization mechanism of DOL, the performance of PDOL composite electrolytes, and the application of PDOL. Furthermore, we provide a perspective on future research directions that need to be emphasized for commercialization of PDOL-based electrolytes in SSLB. The exploration of these schemes facilitates a comprehensive and profound understanding of PDOL-based polymer electrolyte and provides new research ideas to boost them toward practical application in solid-state batteries.

Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has not yet attracted enough attention from researchers to our knowledge. Here, we propose that thermodynamic nucleation overpotential of Zn deposition can be boosted through complexing agent and select sodium L-tartrate (Na-L) as example. Theoretical and experimental characterization reveals L-tartrate anion can partially replace H2O in the solvation sheath of Zn2+, increasing de-solvation energy. Concurrently, the Na+ could absorb on the surface of Zn anode preferentially to inhibit the deposition of Zn2+ aggregation. In consequence, the overpotential of Zn deposition could increase from 32.2 to 45.1 mV with the help of Na-L. The Zn-Zn cell could achieve a Zn utilization rate of 80% at areal capacity of 20 mAh cm−2. Zn-LiMn2O4 full cell with Na-L additive delivers improved stability than that with blank electrolyte. This study also provides insight into the regulation of nucleation overpotential to achieve homogeneous Zn deposition.

Magnesium metal anode holds great potentials toward future high energy and safe rechargeable magnesium battery technology due to its divalent redox and dendrite-free nature. Electrolytes based on Lewis acid chemistry enable the reversible Mg plating/stripping, while they fail to match most cathode materials toward high-voltage magnesium batteries. Herein, reversible Mg plating/stripping is achieved in conventional carbonate electrolytes enabled by the cooperative solvation/surface engineering. Strongly electronegative Cl from the MgCl2 additive of electrolyte impairs the Mg…O = C interaction to reduce the Mg2+ desolvation barrier for accelerated redox kinetics, while the Mg2+-conducting polymer coating on the Mg surface ensures the facile Mg2+ migration and the effective isolation of electrolytes. As a result, reversible plating and stripping of Mg is demonstrated with a low overpotential of 0.7 V up to 2000 cycles. Moreover, benefitting from the wide electrochemical window of carbonate electrolytes, high-voltage (> 2.0 V) rechargeable magnesium batteries are achieved through assembling the electrode couple of Mg metal anode and Prussian blue-based cathodes. The present work provides a cooperative engineering strategy to promote the application of magnesium anode in carbonate electrolytes toward high energy rechargeable batteries.

Colloidal zinc oxide (ZnO) nanocrystals generated from the high temperature and nonaqueous approache are attractive for use in solution-processed electrical and optoelectronic devices. However, the as-prepared colloidal ZnO nanocrystals by this approach are generally capped by ligands with long alkyl-chains, which is disadvantage for solution-processed devices due to hindering charge transport. Here we demonstrate an effective ligand exchange process for the colloidal ZnO nanocrystals from the high temperature and nonaqueous approach by using n-butylamine. The ligand exchange process was carefully characterized. The thin films based on colloidal ZnO nanocrystals with ligand exchange exhibited dramatically enhanced UV photoconductivity.

A solid-state powerful supercapacitor (SC) is fabricated with a substrate of Xerox paper. Its current collector based on a foldable electronic circuit is developed by simply pencil drawing. Thin graphite sheets on paper provide effective channels for electron transmission with a low resistance of 95 Ω sq−1. The conductive organic material of polypyrrole coated on thin graphite sheets acts as the electrode material of the device. The as-fabricated SC exhibits a high specific capacitance of 52.9 F cm−3 at a scan rate of 1 mV s−1. An energy storage unit fabricated by three full-charged series SCs can drive a commercial light-emitting diode robustly. This work demonstrated a simple, versatile and cost-effective method for paper-based devices.

Hiện nay, các vật liệu truyền sáng, tiết kiệm năng lượng và che chắn điện từ đóng vai trò thiết yếu trong việc giảm thiểu tiêu thụ năng lượng trong nhà và cải thiện môi trường điện từ. Bài báo này trình bày việc phát triển một composite cellulose với khả năng truyền sáng quang học xuất sắc, vẫn giữ được hình dạng tự nhiên và cấu trúc sợi của tre. Tre nguyên liệu đã được cải tiến sở hữu khả năng truyền sáng quang học ấn tượng khoảng 60% tại 6,23 mm, độ sáng 1000 lux, độ ổn định hấp thụ nước (tỷ lệ thay đổi khối lượng dưới 4%), độ bền kéo dọc (46,40 MPa) và đặc tính bề mặt (80,2 HD). Những điều này được cho là nhờ vào việc giữ lại cấu trúc rỗng hình tròn tự nhiên của thân tre ở quy mô vĩ mô, cũng như mẫu khuôn xương tre hoàn chỉnh được ngâm trong nhựa UV ở quy mô vi mô. Hơn nữa, một thiết bị nhiều lớp gồm tre nguyên liệu bán trong suốt, tấm tre trong suốt và phim che chắn điện từ thể hiện hiệu suất cách nhiệt đáng kể và hiệu suất bảo quản nhiệt cũng như khả năng che chắn điện từ đạt 46,3 dB. Sự kết hợp giữa khả năng truyền sáng quang học ấn tượng, các tính chất cơ học, hiệu suất nhiệt, và khả năng che chắn điện từ, cùng với tính chất tái tạo và bền vững, cũng như quy trình sản xuất nhanh chóng và hiệu quả, khiến cho vật liệu composite tre này phù hợp cho việc ứng dụng hiệu quả trong các tòa nhà trong suốt, tiết kiệm năng lượng và che chắn điện từ.

Conductive inks based on graphene materials have received significant attention for the fabrication of a wide range of printed and flexible devices. However, the application of graphene fillers is limited by their restricted mass production and the low concentration of their suspensions. In this study, a highly concentrated and conductive ink based on defect-free graphene was developed by a scalable fluid dynamics process. A high shear exfoliation and mixing process enabled the production of graphene at a high concentration of 47.5 mg mL−1 for graphene ink. The screen-printed graphene conductor exhibits a high electrical conductivity of 1.49 × 104 S m−1 and maintains high conductivity under mechanical bending, compressing, and fatigue tests. Based on the as-prepared graphene ink, a printed electrochemical sodium ion (Na+) sensor that shows high potentiometric sensing performance was fabricated. Further, by integrating a wireless electronic module, a prototype Na+-sensing watch is demonstrated for the real-time monitoring of the sodium ion concentration in human sweat during the indoor exercise of a volunteer. The scalable and efficient procedure for the preparation of graphene ink presented in this work is very promising for the low-cost, reproducible, and large-scale printing of flexible and wearable electronic devices.