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Silica-supported nanostructured copper phyllosilicate: Boosting stability, capacity, and conductivity of Li-ion battery Si-based anodes
(2026-11-01)
Shajan, Minnu Gemini
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Chou, Feng Yuan
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Prasanseang, Warot
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Yimtrakarn, Trakarn
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Sooknoi, Tawan
Explosive demand for large-scale rechargeable batteries has driven the search for alternative electrode materials with higher energy density, lower toxicity, lower cost, and more natural abundance. Si-based materials, e.g., Si, SiO, SiO<inf>2</inf>, and silicates have emerged as promising choices, with extremely high capacities from most cost-effective and abundant sources. However, these compounds still suffer from major issues, such as extreme volume change, poor cycling stability, high manufacturing costs, and low conductivity. Herein, we have prepared low-cost porous nanosized silica-supported copper phyllosilicate, x CuPS/SiO<inf>2</inf>, with different Cu loadings and investigated them as anode material in Li cells. Due to the highly dispersed Cu species strongly interacted with nanosphere SiO<inf>2</inf> support matrix, 20CuPS/SiO<inf>2</inf> has been found to deliver a capacity as high as ∼3550 mAh g‒1 at 500 mA g‒1 with an impressive capacity retention of 99% upon conversion reactions with Li+, and a reversible capacity of 2216 mAh g‒1 at 5000 mA g‒1. These values are among the highest ever reported for Si-, silicate-, silica-, and copper oxide-based anodes. Various phases, i.e., CuO, Li<inf>4</inf>SiO<inf>4</inf>, SiO, Si, Li<inf>2</inf>O, Cu, and Li<inf>x</inf>Si, are formed in the SiO<inf>2</inf> nanodomain, as confirmed by various ex situ characterization techniques, and the redox mechanism has been proposed. The components, particularly Li<inf>4</inf>SiO<inf>4</inf>, Li<inf>2</inf>O, and SiO<inf>2</inf>, are shown to help buffer volumetric or structural changes induced by the redox processes. The nanosized composite and the in situ -formed metallic Cu play a crucial role in rapid charge-transfer kinetics. These synergistic effects ultimately result in an unprecedented electrochemical performance of x CuPS/SiO<inf>2</inf> observed in this work.
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Effect of rGO nanosheet loading in SiO2/rGO hybrid nanocomposites for enhancing optoelectrical, physical, and electrochemical properties
(2025-05-01)
Khammahong, Sunisar
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Phrompet, Chaiwat
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Ruttanapun, Chesta
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Sriwong, Chaval
In this study, silicon dioxide nanoparticles (SiO<inf>2</inf>NPs) mixed with reduced graphene oxide nanosheets (rGONS) and hybrid nanocomposites (S/rGOHNCs) were synthesized to study the opto-electrical, physical and electrochemical properties. S/rGOx%HNCs samples with rGONS at various loadings (10, 30, 50, and 70 wt%) were prepared SiO<inf>2</inf>NPs and rGONS suspensions in ultrasonication process by conventional heating. The SiO<inf>2</inf>NPs, rGONS and S/rGOx%HNCs were characterized and properties confirmed by XRD, Raman spectroscopy, FT-IR spectra, UV–Vis, SEM, EDX and TGA techniques. The electrical conductivity carrier concentration, energy gap, and dielectric constant increased with rGONS loading. The S/rGO30HNCs exhibited the highest thermal conductivity, 0.7 W/m·K, and Vickers microhardness, 41.0 HV. The value of electrochemical capacity of S/rGO70HNCs, 66.95 F/g, was due to the appropriate ratio of rGONS and SiO<inf>2</inf>NPs which significantly contributed to increasing redox reaction. The findings offered SiO<inf>2</inf>NPs mixed rGONS hybrid nanocomposites with enhanced optoelectrical (electrical, optical, dielectric), physical (mechanical, thermal) and electrochemical properties.
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Facile Preparation of Montmorillonite/Crosslinked Chitosan Containing Potassium Nitrate Nanocomposites as Eco-Friendly Slow Release Fertilizers
(2023-08-01)
Rukchonlatee, Suparat
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Siriphannon, Punnama
Montmorillonite/tripolyphosphate crosslinked chitosan containing potassium nitrate nanocomposites (MMT/CS-KNO3-TPP) were synthesized by facile incipient wetness impregnation method. The MMT was impregnated stepwise with a mixture of protonated chitosan and KNO<inf>3</inf>, followed by a TPP solution to ionically crosslink with chitosan, resulting in MMT/CS-KNO3-TPP nanocomposites. The initial quantity of KNO<inf>3</inf> to MMT was varied from 0 to 10, 20, and 30 wt%, and the TPP crosslinker was varied according to TPP:chitosan weight ratios of 0:5, 1:5, and 3:5. The resultant MMT/CS-KNO3-TPP nanocomposites composed of the K+ and NO<inf>3</inf>− ions embedded in crosslinked chitosan which intercalated in the MMT basal spacing and covered on MMT external surface. The structure of these nanocomposites could effectively slow the K+ and NO<inf>3</inf>− releases, with the 72- hours cumulative released values (%R) ranging from 20–34% for K+ to 0.4–1.0% for NO<inf>3</inf>−. The MMT/CS-KNO3-TPP nanocomposites with higher TPP concentration could extend the K+ and NO<inf>3</inf>− release times. Total K+ release times were predicted to be in the range of 128–204 days. The presence of MMT/CS-KNO3-TPP nanocomposites in RD43 rice cultivation could promote the growth of RD43 seedlings and roots. Furthermore, the TPP crosslinked chitosan showed physical changes in distilled water, indicating its potential as a long-term nitrogen (N) and phosphorus (P) source for plant nutrients.
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A concise review on design and control of structured natural rubber latex particles as engineering nanocomposites
(2021-10-05)
Wichaita, Waraporn
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Promlok, Duangkamol
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Sudjaipraparat, Narissara
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Sripraphot, Supang
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Suteewong, Teeraporn
In this article, we review the modification of natural rubber (NR) latex into the engineered particles for make use of them in functional nanocomposites. The review focuses on tuning nano-/microstructure and/or composition of NR latex particles by means of surface chemical functionalization, structural modification and incorporation of inorganic nanoparticles (NPs). Due to their polydispersity in size and non-spherical shape with complicated indigenous stabilizers, i.e., proteins and lipids, we first describe the fundamental and common methods for the modification of synthetic polymer latex which become a practical guideline for engineering of NR particles to a variety of designs. Subsequently, the examples of successfully modified NR latex and the involved parameters in the preparation are discussed. The different nature and properties of the modified NR latex compared to the synthetic latex are then depicted. Finally, specific examples of these systems used in a range of applications including nanofillers, controlled releasing materials, textiles, electronics and coatings are demonstrated. The research on modification of NR latex particles would be beneficial to the field of materials science and engineering for the valorization of naturally abundant colloidal polymer to the advanced functional materials in the broader utilization/commercialization in the future.
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Morphology and properties of poly(lactic acid)/ethylene-octene copolymer blends with different organoclay types
(2020-01-01)
Wacharawichanant, Sirirat
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Sriwattana, Attachai
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Yaisoon, Kulaya
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Phankokkruad, Manop
This work studied the morphology, mechanical and thermal properties of poly (lactic acid) (PLA)/ethylene-octene copolymer (EOC) (80/20) blends with different organoclay types. Herein, EOC was introduced to toughening PLA by melt blending and organoclay was used to improve compatibility and tensile properties of the blends. The two organoclay types were nanoclay surface modified with aminopropyltriethoxysilane 0.5-5 wt% and octadecylamine 15-35% (Clay-ASO) and nanoclay surface modified with dimethyl dialkyl (C14-C18) amine 35-45 wt% (Clay-DDA). The organoclay contents were 3, 5 and 7 phr. Scanning electron microscope (SEM) observation results revealed PLA/EOC blends demonstrated a two-phase separation of dispersed EOC phase and PLA matrix phase. The addition of organoclay significantly improved the compatibility between PLA and EOC phases due to EOC droplet size decreased dominantly in PLA matrix, so organoclay could act as an effective compatibilizer. The incorporation of organoclay increased significantly tensile strength of PLA/EOC/organoclay composites while Young’s modulus increased with 5 phr of organoclay. The thermal stability of PLA/EOC blends did not change when compared with neat PLA, and when added Clay-ASO in the blends could improve the thermal stability of the PLA/EOC blends.

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