Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fund...Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics.展开更多
Hydrothermal treatment of cellulose is a promising green route for bioenergy and biochemical production,yet it requires investigation of the underlying mechanisms.In this study,the effects of cellulose crystallinity a...Hydrothermal treatment of cellulose is a promising green route for bioenergy and biochemical production,yet it requires investigation of the underlying mechanisms.In this study,the effects of cellulose crystallinity and decoupled temperature and pressure conditions on cellulose conversion and product distribution were investigated.Microcrystalline cellulose was ball-milled for varying durations,leading to a reduction in crystallinity,with 4 h of milling sufficient to achieve near-complete amorphization.Unlike concurrent recrystallization and hydrolysis observed under autogenous pressure,decoupled conditions significantly accelerated hydrolysis of cellulose.Notably,lower crystallinity cellulose exhibited significant improvements in glucose and 5-HMF yields,with 4-h ball milling showing optimal performance among all samples.Furthermore,carbon sub-micron spheres were largely produced,which were confirmed via PTFE encapsulation experiments to primarily consist of secondary char deriving from re-polymerization and condensation reactions of the liquid phase.Overall,this study demonstrates that lower crystallinity not only facilitates hydrolysis but also accelerates the carbonization processes under decoupled pressure conditions,highlighting its potential for efficient biomass conversion into valuable products.展开更多
基金supported by National Natural Science Foundation of China(32494793).
文摘Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics.
基金The financial support from the Beijing Natural Science Foundation(JQ24053)National Natural Science Foundation of China(52276202)+3 种基金Natural Science Foundation of Shanxi Province(202403021211024,202403021212148)Yunnan Major Scientific and Technological Projects(202302AQ370003)Huaneng Group Science and Technology Research Project(HNKJ23-H71)Tsinghua University Initiative Scientific Research Program are gratefully acknowledged.
文摘Hydrothermal treatment of cellulose is a promising green route for bioenergy and biochemical production,yet it requires investigation of the underlying mechanisms.In this study,the effects of cellulose crystallinity and decoupled temperature and pressure conditions on cellulose conversion and product distribution were investigated.Microcrystalline cellulose was ball-milled for varying durations,leading to a reduction in crystallinity,with 4 h of milling sufficient to achieve near-complete amorphization.Unlike concurrent recrystallization and hydrolysis observed under autogenous pressure,decoupled conditions significantly accelerated hydrolysis of cellulose.Notably,lower crystallinity cellulose exhibited significant improvements in glucose and 5-HMF yields,with 4-h ball milling showing optimal performance among all samples.Furthermore,carbon sub-micron spheres were largely produced,which were confirmed via PTFE encapsulation experiments to primarily consist of secondary char deriving from re-polymerization and condensation reactions of the liquid phase.Overall,this study demonstrates that lower crystallinity not only facilitates hydrolysis but also accelerates the carbonization processes under decoupled pressure conditions,highlighting its potential for efficient biomass conversion into valuable products.
