Method for preparing carbon quantum dots by using bagasse as carbon source with chemical oxidation process

Abstract

The invention belongs to the technical field of material synthesis, and discloses a method for preparing carbon quantum dots by using bagasse as a carbon source with a chemical oxidation process. Themethod comprises the following steps: high temperature carbonization is carried out for the bagasse at 300-700 DEG C for 2-7 hours, in order to obtain carbonized black solids, and the solids are grinded into black powder; the black powder is dispersed in acetic acid and 30wt% hydrogen peroxide, ultrasonic treatment is carried out, heating reflux is carried out at 100-140 DEG C for 6-24 hours, andcooling is carried out; the solution is filtered in order to remove impurities of large particles and solid substances which are not completely reacted; centrifugation is carried out at the rotation number of 4000-12000r / min for 10-60 minutes, dialysis of supernatant is carried out for 12-48 hours, and an aqueous solution of carbon quantum dots is obtained. The preparation process is simple, professional apparatus and equipment are not needed, tedious aftertreatment is not needed; the preparation condition is mild, strong acid and highly basic as well as other poisonous and harmful substancesare not needed; prepared carbon quantum dots have good surface morphology and high fluorescence intensity.

Description

technical field

[0001] The invention belongs to the technical field of material synthesis, and relates to a method for preparing carbon quantum dots by using bagasse as a carbon source and utilizing a chemical oxidation method. Background technique

[0002] Bagasse is the main by-product of the sugar industry. Sugar cane is pressed to form bagasse, and about 1 ton of bagasse is produced for every ton of sucrose produced. Bagasse generally contains 90%-92% dry matter, including 1.5% crude protein, 44%-46% crude fiber, 0.7% crude fat, 42% nitrogen-free extract, 2%-3% crude ash; no SO 2 The crude fiber contains about 46% cellulose, 25% hemicellulose, 20% lignin, and about 9% other substances. It is a clean, high-quality and sustainable biomass energy. Compared with crop straw, bagasse has very few pesticide residues, but due to the high degree of lignification of bagasse, uncoordinated nutrients, etc., coupled with the backwardness of transformation and utilization technology,...

Examples

Embodiment 1

[0022] Embodiment 1: a kind of use bagasse as carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprise the steps:

[0023] (1) Carry out high-temperature carbonization of bagasse at 400° C. to obtain a carbonized black solid, which is ground to obtain a black powder.

[0024] (2) Take 0.2 g of the black powder obtained in step (1) in a 250 mL round bottom flask, add 40 mL of acetic acid (analytical grade) and 20 mL of 30% hydrogen peroxide, ultrasonicate for 50 min, heat to reflux at 100°C for 16 h, and cool.

[0025] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 4000r / min for 20min, and dialyze the supernatant for 24h. An aqueous solution of carbon quantum dots is obtained.

Embodiment 2

[0026] Embodiment 2: a kind of use bagasse as a carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprising the following steps:

[0027] (1) Carry out high-temperature carbonization of bagasse at 500°C to obtain a carbonized black solid, which is ground to obtain a black powder.

[0028] (2) Take 0.1 g of the black powder prepared in step (1) in a 250 mL round bottom flask, add 20 mL of acetic acid (analytical grade) and 10 mL of 30% hydrogen peroxide, ultrasonicate for 30 min, heat to reflux at 100°C for 10 h, and cool.

[0029] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 8000r / min for 20min, and dialyze the supernatant for 12h. An aqueous solution of carbon quantum dots is obtained.

Embodiment 3

[0030] Embodiment 3: a kind of use bagasse as a carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprising the following steps:

[0031] (1) Carry out high-temperature carbonization of bagasse at 700°C to obtain a carbonized black solid, which is ground to obtain a black powder.

[0032] (2) Take 0.3 g of the black powder obtained in step (1) in a 250 mL round bottom flask, add 40 mL of acetic acid (analytical grade) and 80 mL of 30% hydrogen peroxide, ultrasonicate for 30 min, heat to reflux at 100 °C for 12 h, and cool.

[0033] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 4000r / min for 20min, and dialyze the supernatant for 24h. An aqueous solution of carbon quantum dots is obtained.

technical field

[0001] The invention belongs to the technical field of material synthesis, and relates to a method for preparing carbon quantum dots by using bagasse as a carbon source and utilizing a chemical oxidation method. Background technique

[0002] Bagasse is the main by-product of the sugar industry. Sugar cane is pressed to form bagasse, and about 1 ton of bagasse is produced for every ton of sucrose produced. Bagasse generally contains 90%-92% dry matter, including 1.5% crude protein, 44%-46% crude fiber, 0.7% crude fat, 42% nitrogen-free extract, 2%-3% crude ash; no SO 2 The crude fiber contains about 46% cellulose, 25% hemicellulose, 20% lignin, and about 9% other substances. It is a clean, high-quality and sustainable biomass energy. Compared with crop straw, bagasse has very few pesticide residues, but due to the high degree of lignification of bagasse, uncoordinated nutrients, etc., coupled with the backwardness of transformation and utilization technology,...

Examples

Embodiment 1

[0022] Embodiment 1: a kind of use bagasse as carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprise the steps:

[0023] (1) Carry out high-temperature carbonization of bagasse at 400° C. to obtain a carbonized black solid, which is ground to obtain a black powder.

[0024] (2) Take 0.2 g of the black powder obtained in step (1) in a 250 mL round bottom flask, add 40 mL of acetic acid (analytical grade) and 20 mL of 30% hydrogen peroxide, ultrasonicate for 50 min, heat to reflux at 100°C for 16 h, and cool.

[0025] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 4000r / min for 20min, and dialyze the supernatant for 24h. An aqueous solution of carbon quantum dots is obtained.

Embodiment 2

[0026] Embodiment 2: a kind of use bagasse as a carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprising the following steps:

[0027] (1) Carry out high-temperature carbonization of bagasse at 500°C to obtain a carbonized black solid, which is ground to obtain a black powder.

[0028] (2) Take 0.1 g of the black powder prepared in step (1) in a 250 mL round bottom flask, add 20 mL of acetic acid (analytical grade) and 10 mL of 30% hydrogen peroxide, ultrasonicate for 30 min, heat to reflux at 100°C for 10 h, and cool.

[0029] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 8000r / min for 20min, and dialyze the supernatant for 12h. An aqueous solution of carbon quantum dots is obtained.

Embodiment 3

[0030] Embodiment 3: a kind of use bagasse as a carbon source to utilize chemical oxidation to prepare carbon quantum dots, comprising the following steps:

[0031] (1) Carry out high-temperature carbonization of bagasse at 700°C to obtain a carbonized black solid, which is ground to obtain a black powder.

[0032] (2) Take 0.3 g of the black powder obtained in step (1) in a 250 mL round bottom flask, add 40 mL of acetic acid (analytical grade) and 80 mL of 30% hydrogen peroxide, ultrasonicate for 30 min, heat to reflux at 100 °C for 12 h, and cool.

[0033] (3) Filter the solution obtained in step (2) to remove large particles of impurities and unreacted solid matter. Centrifuge at 4000r / min for 20min, and dialyze the supernatant for 24h. An aqueous solution of carbon quantum dots is obtained.

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