The present work suggested the use of waste oil palm frond as an alternative precursor for nitrogendoped carbon quantum dots(NCQDs)and proposed a straightforward in-situ hydrothermal method for the preparation of NCQD...The present work suggested the use of waste oil palm frond as an alternative precursor for nitrogendoped carbon quantum dots(NCQDs)and proposed a straightforward in-situ hydrothermal method for the preparation of NCQDs/TiO_(2)nanocomposites.The elemental composition,morphological,structural and optical characteristics of NCQDs/TiO_(2)nanocomposites have been comprehensively investigated.The successful grafting of NCQDs on TiO_(2)matrix was confirmed by the formation of Ti AOAC bond and the electronic coupling between theπ-states of NCQDs and the conduction band of TiO_(2).For the first time,the oil palm frond-derived NCQDs/TiO_(2)was adopted in the photodegradation of methylene blue(MB)under visible-light irradiation.As a result,the photocatalytic efficiency of NCQDs/TiO_(2)nanocomposites(86.16%)was 2.85 times higher than its counterpart TiO_(2)(30.18%).The enhanced performance of nanocomposites was attributed to the pivotal roles of NCQDs serving as electron mediator and visiblelight harvester.Besides,the optimal NCQDs loading was determined at 4 ml while the removal efficiency of NCQDs/TiO_(2)-4 was the highest at a catalyst dosage of 1 g.L^(-1)under alkaline condition.This research work is important as it proposed a new insight to the preparation of biomass-based NCQDs/TiO_(2)using a facile synthetic method,which offers a green and sustainable water remediation technology.展开更多
Natural fibers have become essential elements to produce composites, which have the renewability, sustainability, low cost and less health hazardous. Natural wastes improved the physical and mechanical properties of p...Natural fibers have become essential elements to produce composites, which have the renewability, sustainability, low cost and less health hazardous. Natural wastes improved the physical and mechanical properties of polyester-based composites. Reinforced polyester composites with natural fibers are spread widely in recent decades as an alternative to synthetics. This paper deals with effectiveness of palm fronds when they were added to a polyester. Percentage of palm fibers with respect to polyester is considered through present work. A Pin-on-disc tribometer has been used in experimental work under external forces, and the correlations of coefficient of friction have been used to make analysis of the experimental results. Ibertest universal testing machine was used to measure the tensile strength at a crosshead speed of 8 mm/min. The experimental analysis shows the improvement of properties of the used reinforced polyester, where, the results show that the highest values of coefficient of friction are 1.16667 for 5 N load and the lowest value is 0.55 for 9 N load. And the change for load 11 N is not significant. And also, 7.01 MPa is the highest value for tensile strength with the lowest value of modulus of rigidity 5.84 when the palm frond content is 3% and the lowest value of tensile test is 4.81 MPa with the highest value of modulus of rigidity 11.9 when 21% content.展开更多
基金the funding provided by Universiti Tunku Abdul Rahman Research fund(IPSR/RMC/UTARRF/2020-C2/C06)Centre for Photonics and Advanced Materials Research(CPAMR,UTAR)for their support。
文摘The present work suggested the use of waste oil palm frond as an alternative precursor for nitrogendoped carbon quantum dots(NCQDs)and proposed a straightforward in-situ hydrothermal method for the preparation of NCQDs/TiO_(2)nanocomposites.The elemental composition,morphological,structural and optical characteristics of NCQDs/TiO_(2)nanocomposites have been comprehensively investigated.The successful grafting of NCQDs on TiO_(2)matrix was confirmed by the formation of Ti AOAC bond and the electronic coupling between theπ-states of NCQDs and the conduction band of TiO_(2).For the first time,the oil palm frond-derived NCQDs/TiO_(2)was adopted in the photodegradation of methylene blue(MB)under visible-light irradiation.As a result,the photocatalytic efficiency of NCQDs/TiO_(2)nanocomposites(86.16%)was 2.85 times higher than its counterpart TiO_(2)(30.18%).The enhanced performance of nanocomposites was attributed to the pivotal roles of NCQDs serving as electron mediator and visiblelight harvester.Besides,the optimal NCQDs loading was determined at 4 ml while the removal efficiency of NCQDs/TiO_(2)-4 was the highest at a catalyst dosage of 1 g.L^(-1)under alkaline condition.This research work is important as it proposed a new insight to the preparation of biomass-based NCQDs/TiO_(2)using a facile synthetic method,which offers a green and sustainable water remediation technology.
文摘Natural fibers have become essential elements to produce composites, which have the renewability, sustainability, low cost and less health hazardous. Natural wastes improved the physical and mechanical properties of polyester-based composites. Reinforced polyester composites with natural fibers are spread widely in recent decades as an alternative to synthetics. This paper deals with effectiveness of palm fronds when they were added to a polyester. Percentage of palm fibers with respect to polyester is considered through present work. A Pin-on-disc tribometer has been used in experimental work under external forces, and the correlations of coefficient of friction have been used to make analysis of the experimental results. Ibertest universal testing machine was used to measure the tensile strength at a crosshead speed of 8 mm/min. The experimental analysis shows the improvement of properties of the used reinforced polyester, where, the results show that the highest values of coefficient of friction are 1.16667 for 5 N load and the lowest value is 0.55 for 9 N load. And the change for load 11 N is not significant. And also, 7.01 MPa is the highest value for tensile strength with the lowest value of modulus of rigidity 5.84 when the palm frond content is 3% and the lowest value of tensile test is 4.81 MPa with the highest value of modulus of rigidity 11.9 when 21% content.
基金Supported by New Century Excellent Talents Project of the Ministry of Education (2006)Talents Introduction Fund of Tianjin University of Science and Technology (20060432 and 20080216)~~