Method for preparing patterned suspended nano carbon-based film through laser induction

Abstract

The invention discloses a method for preparing a patterned suspended nano-carbon-based film through laser induction, which comprises the following steps: 1) adding a light-absorbing nano-carbon material into an alcohol-water solution of graphene oxide, and carrying out ultrasonic treatment to obtain a nano-carbon-based multi-element compound solution; 2) evaporating the obtained compound solution to form a self-assembled nano carbon film; continuously injecting a multi-element compound solution to the lower part of the obtained film until the obtained film is in full contact with the multi-element compound solution; then carrying out laser scanning on the surface of the film to obtain a patterned nano carbon-based film; 3) continuously evaporating the obtained film, extracting the solution below the film to separate the film from the solution, and drying; and finally, taking down the obtained film, and carrying out a heating reduction reaction to prepare the patterned suspended nano carbon-based film. The film provided by the invention has good uniformity and integrity, can realize high-precision patterning, and is suitable for the fields of micro-nano electromechanical systems, high-thermal-conductivity materials, energy storage and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of functional materials and preparation thereof, and specifically relates to a method for preparing a patterned suspended nano carbon-based film by laser induction. Background Art

[0002] Suspended graphene films have great application potential in the fields of micro-nano electromechanical systems, high thermal conductivity materials, energy storage, etc., due to their easy deformation, high conductivity, high modulus, and excellent chemical stability. However, currently suspended graphene films are mostly prepared by chemical vapor deposition, which requires a delicate film transfer process, resulting in complex processes and easy damage during the preparation process. Therefore, the film size is severely limited, and generally only micron-sized film products can be prepared.

[0003] Using graphene oxide (GO) as raw material, large-sized graphene films can be prepared through interfacial self-assembly technology, and the process is simple, which is considered to be an ideal method for preparing graphene films in the future. However, this method also requires a membrane transfer process, and the quality of the film is difficult to guarantee. In addition, the graphene film prepared by chemical reduction of GO has many molecular structural defects and cannot be patterned in a suspended form, which not only reduces the performance advantages of graphene itself, but also limits its application scenarios, seriously hindering the development and application of suspended graphene films.

[0004] In response to the above problems, how to get rid of the limitations of the membrane transfer process by regulating the material system and preparation process, improve the quality of reduced GO, and realize the free patterning of suspended graphene films is an important issue that needs to be solved urgently. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for laser-induced preparation of patterned suspended nano-carbon-based films in response to the problems and shortcomings of the prior art, improve the quality of graphene after laser reduction and achieve patterning, significantly reduce the interaction force between the self-assembled GO film and the solution through a compound solvent system, thereby getting rid of the dependence on the membrane transfer process and achieving the preparation of patterned suspended nano-carbon material films.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0008] 1) Preparation of nano-carbon-based multi-component compound solution;

[0009] Adding light-absorbing nano-carbon material to an alcohol-water solution of graphene oxide, and ultrasonically treating the solution to obtain a nano-carbon-based multi-component composite solution;

[0010] 2) Interfacial self-assembly of nanocarbon-based films and their laser-induced patterning;

[0011] The nano-carbon-based multi-component composite solution is placed in a container with a smooth inner wall, evaporated under heating or vacuum environment, and a self-assembled nano-carbon film is formed at the interface between the solution and the air; then the nano-carbon-based multi-component composite solution is continuously injected under the obtained self-assembled nano-carbon film, so that the obtained nano-carbon film is fully in contact with the multi-component composite solution in the container (filling the local gap formed between the obtained film and the original solution after evaporation); and then a laser in the ultraviolet-visible light band is used to scan the nano-carbon film according to a designed scanning path to induce the reduction of GO to graphene, so as to obtain a patterned nano-carbon-based film;

[0012] 3) Suspension preparation of patterned nanocarbon-based films;

[0013] The obtained patterned nano-carbon-based film is further subjected to evaporation treatment, and the solution under the film is extracted to separate the nano-carbon film from the solution, and dried to obtain a patterned nano-carbon film suspended on the inner wall of the container;

[0014] Finally, the obtained patterned nano-carbon film is removed, subjected to a heating reduction reaction, and dried to obtain the patterned suspended nano-carbon-based film.

[0015] In the above solution, the container can be made of glass or stainless steel, and specifically can be a beaker, a glass culture dish or a stainless steel cup.

[0016] In the above scheme, the concentration of graphene oxide in the alcohol aqueous solution of graphene oxide is 0.5 to 5 mg / mL.

[0017] In the above scheme, the concentration of the alcohol solvent in the alcohol aqueous solution of graphene oxide is 89.5-90 vol%.

[0018] In the above scheme, the alcohol solvent is a small molecule alcohol solvent.

[0019] Furthermore, the alcohol solvent may be selected from one or more of methanol, ethanol, propanol, etc.

[0020] Preferably, the step of preparing the alcoholic aqueous solution of graphene oxide comprises: preparing a graphene oxide alcoholic solution having a water content of less than 0.1 vol%; then adding water thereto, and ultrasonically treating the solution to obtain the alcoholic aqueous solution of graphene oxide.

[0021] Furthermore, the volume ratio of the graphene oxide alcohol solution to water is (7.5-9.5):1.

[0022] Furthermore, in the step of preparing the alcohol-water solution of graphene oxide, the ultrasonic treatment time is 1 to 2 hours.

[0023] In the above scheme, the ultrasonic treatment time in step 1) is 30 to 60 minutes.

[0024] In the above scheme, the light-absorbing nano-carbon material can be selected from one or more of carboxylated carbon nanotubes, carboxylated fullerenes, acidified nano-carbon black, and the like.

[0025] Furthermore, the mass ratio of the light-absorbing nano-carbon material to graphene oxide is 1 to 6:100.

[0026] In the above scheme, the heating temperature used in the evaporation step is 40-70°C; and the vacuum condition is below 0.085MPa.

[0027] In the above scheme, the thickness of the self-assembled nano-carbon film in step 2) is 50nm to 2μm.

[0028] In the above scheme, the wavelength of the laser in the ultraviolet-visible light band is 200 to 700 nm.

[0029] Furthermore, the laser power is 200-400 mW.

[0030] In the above scheme, the scanning rate is 20 to 380 mm / s.

[0031] In the above scheme, the evaporation treatment time in step 3) is 20 to 30 minutes.

[0032] In the above scheme, the drying temperature in step 3) is 40 to 80° C. and the drying time is 20 to 40 minutes.

[0033] In the above scheme, the reduction step in step 3) adopts a reducing atmosphere, wherein the heating temperature adopted is 70-90° C. and the time is 4-8 hours; the reducing atmosphere adopted is one of hydrogen iodide vapor, hydrazine hydrate vapor, etc.

[0034] In the above scheme, the temperature used in the vacuum drying step is 120-150° C. and the time is 8-12 hours.

[0035] The patterned suspended nanocarbon-based film prepared according to the above scheme has a low D peak intensity / G peak intensity in the Raman spectrum (0.2-0.4) and a low degree of film defects; it can improve the quality of nanocarbon material films and maintain an independent suspended state, and can be applied to micro-nano electromechanical systems, high thermal conductivity materials, energy storage and other fields.

[0036] Compared with the prior art, the beneficial effects of the present invention include:

[0037] 1) The present invention introduces light-absorbing nano-carbon materials to enhance the photothermal effect of graphene oxide (GO) film under laser conditions, which can significantly improve the quality of laser-reduced GO film. At the same time, combined with the evaporation of the alcohol-water-based multi-component composite solution and the immersion conditions of the composite solution, the suspension, integrity and uniformity of the laser-scanned patterned film can be effectively guaranteed, and it is conducive to the refinement of the pattern;

[0038] 2) The present invention promotes the preparation of self-assembled suspended films by evaporating a multi-component solvent system; at the same time, during the laser-induced reduction process, the liquid immersion environment constructed by re-injection can effectively limit the spread of heat, and combined with the secondary evaporation process, it can promote the uniformity, integrity and high-precision patterning of the film.

[0039] 3) The method described in the present invention breaks away from the limitations of the traditional film transfer process, can effectively simplify the preparation process, avoids the problem of film breakage during the transfer process, and can prepare large-sized suspended nanocarbon material films; the resulting patterned suspended nanocarbon material film has high quality and can maintain a self-supporting suspension state and structural integrity, and is suitable for micro-nano electromechanical systems, high thermal conductivity materials, energy storage and other fields, and can effectively broaden the application scenarios of suspended nanocarbon films. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a photo of GO after film formation at the gas-liquid interface in Example 1;

[0041] Figure 2 The UV-visible absorption spectra of the nano-carbon-based multi-component composite solutions prepared in Example 1 and Comparative Example 1, respectively; wherein Example 1 is a high-absorbance GO composite solution, and Comparative Example 1 is a GO composite solution;

[0042] Figure 3 (a) a photograph of the suspended patterned nano-carbon-based film prepared in Example 1, (b) a photograph of the suspended nano-carbon-based film after laser scanning in Comparative Example 2, and (c) a photograph of the non-suspended patterned nano-carbon-based film obtained in Comparative Example 3;

[0043] Figure 4 The Raman spectra of the films obtained in Example 1 and Comparative Example 1 are shown. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] The applicant will further explain the present invention in detail below in conjunction with specific embodiments so that those skilled in the art can more clearly understand the present invention. However, the following content should not be construed as limiting the scope of protection of the claims of the present invention.

[0046] The chemical reagents and solvents used in the examples are all analytically pure. The stirring is carried out using a magnetic stirrer.

[0047] In the following embodiments, the method for preparing a patterned suspended nanocarbon material film by laser induction comprises the following steps:

[0048] 1) Preparation of high absorbance GO multi-component solution:

[0049] A GO aqueous solution was prepared by an improved Hummers method; the prepared GO aqueous solution was centrifuged at a centrifugal speed of 10000-12000 r / min for 60-90 min, the supernatant was poured out, a small molecule alcohol solvent was added and stirred evenly, and the supernatant was poured out after continuing to centrifuge at a centrifugal speed of 10000-12000 r / min for 60-90 min, a small molecule alcohol solvent was added and stirred evenly, and the above operation was repeated 6-10 times to obtain a GO alcohol solution with a water content of less than 0.1% (the concentration of GO is 0.53-6.6 mg / ml); a GO alcohol-water composite solution with a volume ratio of GO alcohol solution to distilled water = (7.5-9.5):1 was prepared, and the GO concentration was prepared to be 0.5-5 mg / mL, and a highly absorbent nanocarbon material was added after ultrasonication for 1-2 hours, and the concentration was 1-6% of the GO concentration, and a highly absorbent GO multi-component composite solution was obtained after ultrasonication for 30-60 minutes;

[0050] 2) Interfacial self-assembly of nanocarbon thin films and their laser-induced patterning;

[0051] The high-absorbency GO multi-component composite solution is placed in a beaker, stainless steel cup or other container, and placed in an atmosphere or vacuum environment at 40-70°C for evaporation, and GO self-assembles into a film at the interface between the solution and the air; when the film is visible to the naked eye, continue evaporation for 10-20 minutes to obtain a thicker (50nm-2μm) self-assembled nano-carbon film; a high-absorbency GO multi-component composite solution is injected under the film with a syringe (the composite solution is injected along the edge of the film with a syringe until the gap formed between the film after evaporation and the original composite solution in the container is filled), so that the nano-carbon material film is fully in contact with the solution; a laser in the ultraviolet-visible light band (200-700nm wavelength) is used to scan the nano-carbon material film to induce the reduction of GO to graphene, and the laser scanning path is controlled to achieve graphene patterning;

[0052] 3) Suspension preparation of patterned nanocarbon films;

[0053] The patterned nano-carbon film obtained in step 2) is further evaporated for 20 to 30 minutes, and the solution under the film is pumped away, so that the nano-carbon material film is separated from the solution; and the nano-carbon material film is further dried at 40 to 80° C. for 20 to 40 minutes to obtain a suspended nano-carbon material film;

[0054] After the obtained nano-carbon material film is removed, it is placed in a reducing atmosphere at 70-90° C. for further reduction for 4-8 hours, and then vacuum dried at 120-150° C. for 8-12 hours to obtain a patterned suspended nano-carbon material film.

[0055] Furthermore, in step 1), the GO aqueous solution is centrifuged at a centrifugal speed of 11000 r / min for 80 min and then the supernatant is discarded.

[0056] Furthermore, the small molecule alcohol solvent added in step 1) is one or a mixture of methanol, ethanol, propanol.

[0057] Furthermore, the centrifugation in step 1) is repeated 8 times.

[0058] Furthermore, the highly light-absorbing nano-carbon material added in step 1) is one or a mixture of carboxylated carbon nanotubes, carboxylated fullerenes, and acidified nano-carbon black.

[0059] Furthermore, in step 1), after ultrasonication for 40 minutes, a high-absorbency GO multi-component complex solution is obtained.

[0060] Furthermore, in step 2), the high absorbance GO multi-component compound solution is placed in an atmospheric environment at 60° C. to evaporate.

[0061] Furthermore, the evaporation in step 2) is continued for 15 minutes to obtain a thicker (50 nm to 2 μm) self-assembled nanocarbon film.

[0062] Furthermore, the laser wavelength used in step 2) is one of 650nm, 450nm, 405nm, and 355nm, and the power is 300mW.

[0063] Furthermore, in step 3), the patterned nano-carbon material film is evaporated for another 25 minutes.

[0064] Furthermore, in step 3), drying is continued at 60° C. for 30 min to obtain a suspended nano-carbon film.

[0065] Furthermore, in step 3), the reduction is further carried out in a reducing atmosphere at 80° C. for 6 hours.

[0066] Furthermore, the reducing atmosphere used in step 3) is one of hydrogen iodide vapor, hydrazine hydrate vapor, etc.

[0067] Furthermore, in step 3), vacuum drying is performed at 130° C. for 10 h to obtain a patterned suspended nano-carbon-based film.

[0068] Specific embodiments include the following:

[0069] Example 1

[0070] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0071] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0072] GO aqueous solution was prepared by improving the Hummers method; the prepared GO aqueous solution was centrifuged at a centrifugal speed of 11000r / min for 80min, the supernatant was poured out, ethanol solvent was added and stirred evenly, and the supernatant was poured out after continuing to centrifuge at a centrifugal speed of 11000r / min for 80min, ethanol solvent was added and stirred evenly, and the above operation was repeated 8 times to obtain a GO alcohol solution with a water content of less than 0.1% (GO concentration was 3.3mg / ml); the GO alcohol solution and distilled water were prepared into a GO alcohol-water composite solution in a volume ratio of 9:1, and the GO concentration was prepared to 3mg / mL. After ultrasonication for 1.5h, carboxylated carbon nanotubes (Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with a length of <10μm, a diameter of 30-80nm, and a purity of 95wt%) were added, and the concentration of carbon nanotubes in the obtained solution system was 0.12mg / mL. After ultrasonication for 40min, a high-absorbance GO multi-component composite solution was obtained;

[0073] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0074] The high-absorbance GO multi-component solution was placed in a beaker and evaporated in a vacuum oven at 60°C and 0.1MPa. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, the evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of about 130nm.

[0075] A high-absorbance GO multi-component solution was injected under the membrane with a syringe to make the nano-carbon film fully contact with the solution, and a laser with a wavelength of 450 nm (power 300 mW) was scanned on the nano-carbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0076] 3) Suspension preparation of patterned nanocarbon films;

[0077] The patterned nano-carbon film obtained in step 2) is further evaporated for 25 min (the evaporation conditions are the same as those in step 2), and the solution under the film is pumped away to separate the nano-carbon film from the solution; and the film is further dried at 60° C. for 30 min to obtain a suspended nano-carbon film;

[0078] After the nanocarbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon-based film.

[0079] Example 2

[0080] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0081] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0082] The GO alcohol solution described in Example 1 and distilled water were mixed in a volume ratio of 9:1 to prepare a GO alcohol-water composite solution, with a GO concentration of 3 mg / mL. After ultrasonication for 1.5 h, carboxylated fullerene (provided by Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with a hydroxyl number of 18 to 28, prepared by an arc method) was added, and its concentration in the obtained solution system was 0.12 mg / mL. After ultrasonication for 40 min, a high-absorbency nano-carbon-based multi-component composite solution was obtained;

[0083] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0084] The high-absorbance nanocarbon-based multi-component composite solution was placed in a beaker and placed in a vacuum oven at 60°C and 0.1MPa for evaporation. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of 130nm.

[0085] A high-absorbency nanocarbon-based multi-component solution was injected under the membrane with a syringe to make the nanocarbon film fully contact with the solution, and a laser with a wavelength of 450 nm (power 300 mW) was used to scan the nanocarbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0086] 3) Suspension preparation of patterned nanocarbon films;

[0087] The patterned nano-carbon film obtained in step 2) is evaporated for 25 minutes (the evaporation conditions are the same as those in step 2), and the solution under the film is pumped away to separate the nano-carbon film from the solution; and the film is dried at 60° C. for 30 minutes to obtain a suspended nano-carbon film;

[0088] After the nanocarbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon-based film.

[0089] Example 3

[0090] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0091] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0092] The GO alcohol solution described in Example 1 and distilled water were mixed in a volume ratio of 9:1 to prepare a GO alcohol-water composite solution, with a GO concentration of 3 mg / mL. After ultrasonication for 1.5 h, acidified nano-carbon black (provided by Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with a particle size of 30-45 nm) was added, and its concentration in the obtained solution system was 0.12 mg / mL. After ultrasonication for 40 min, a high-absorbency nano-carbon-based multi-component composite solution was obtained;

[0093] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0094] The high-absorbance nanocarbon-based multi-component composite solution was placed in a beaker and placed in a vacuum oven at 60°C and 0.1MPa for evaporation. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of 130nm.

[0095] A high-absorbency nanocarbon-based multi-component solution was injected under the membrane with a syringe to make the nanocarbon film fully contact with the solution, and a laser with a wavelength of 450 nm (power 300 mW) was used to scan the nanocarbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0096] 3) Suspension preparation of patterned nanocarbon films;

[0097] The patterned nano-carbon film obtained in step 2) is further evaporated for 25 minutes, and the solution under the film is pumped away, so that the nano-carbon film is separated from the solution; and drying is continued at 60° C. for 30 minutes to obtain a suspended nano-carbon film;

[0098] After the nanocarbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon-based film.

[0099] Example 4

[0100] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0101] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0102] The GO alcohol solution described in Example 1 and distilled water were mixed in a volume ratio of 8:2 to prepare a GO alcohol-water composite solution, with a GO concentration of 2 mg / mL. After ultrasonication for 1.5 h, carboxylated carbon nanotubes (Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with a length of <10 μm, a diameter of 30-80 nm, and a purity of 95 wt%) were added at a concentration of 0.08 mg / mL. After ultrasonication for 40 min, a high-absorbency nano-carbon-based multi-component composite solution was obtained;

[0103] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0104] The high-absorbance nanocarbon-based multi-component composite solution was placed in a beaker and evaporated in a vacuum oven at 60°C and 0.1MPa. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, the evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of 100nm.

[0105] A high-absorbency nanocarbon-based multi-component solution was injected under the membrane with a syringe to make the nanocarbon film fully contact with the solution, and a laser with a wavelength of 405 nm (power 300 mW) was used to scan the nanocarbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0106] 3) Suspension preparation of patterned nanocarbon films;

[0107] The patterned nanocarbon film obtained in step 2) is further evaporated for 25 minutes, and the solution under the film is pumped away to separate the nanocarbon film from the solution; the film is further dried at 60°C for 30 minutes to obtain a suspended nanocarbon film; the nanocarbon film is removed and placed in 80°C hydrogen iodide vapor for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon film.

[0108] Example 5

[0109] A method for preparing a patterned suspended nanocarbon-based film by laser induction comprises the following steps:

[0110] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0111] The GO alcohol solution and distilled water described in Example 1 were mixed in a volume ratio of 9.5:0.5 to prepare a GO alcohol-water composite solution, with a GO concentration of 4 mg / mL. After ultrasonication for 1.5 h, carboxylated carbon nanotubes (provided by Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., with a length of <10 μm, a diameter of 30-80 nm, and a purity of 95 wt%) were added at a concentration of 0.16 mg / mL. After ultrasonication for 40 min, a high-absorbency nano-carbon-based multi-component composite solution was obtained;

[0112] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0113] The high-absorbance nanocarbon-based multi-component composite solution was placed in a beaker, stainless steel cup or other container, and placed in a vacuum oven at 60°C and 0.1MPa for evaporation. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, the evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of 150nm.

[0114] A high-absorbance GO multi-component solution was injected under the membrane with a syringe to make the nanocarbon film fully contact with the solution, and a laser with a wavelength of 355 nm (power 300 mW) was used to scan the nanocarbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0115] 3) Suspension preparation of patterned nanocarbon films;

[0116] The patterned nano-carbon film obtained in step 2) is further evaporated for 25 minutes, and the solution under the film is pumped away, so that the nano-carbon film is separated from the solution; and the nano-carbon film is further dried at 60° C. for 30 minutes to obtain a suspended nano-carbon film;

[0117] After the nanocarbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon film.

[0118] Comparative Example 1

[0119] A method for laser-induced suspended graphene patterning comprises the following steps:

[0120] 1) Preparation of nano-carbon-based multi-component compound solution:

[0121] The GO alcohol solution described in Example 1 and distilled water were mixed in a volume ratio of 9:1 to prepare a GO alcohol-water composite solution, with a GO concentration of 3 mg / mL, and the nano-carbon-based multi-component composite solution was obtained after ultrasonic treatment for 1.5 hours;

[0122] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0123] The nanocarbon-based multi-component composite solution was placed in a beaker, stainless steel cup or other container, and placed in a vacuum oven at 60°C and 0.1MPa for evaporation. GO self-assembled into a film at the interface between the solution and the air. When the film was visible to the naked eye, the evaporation was continued for 15 minutes to obtain a self-assembled nanocarbon film with an average thickness of 125nm.

[0124] A nanocarbon-based multi-component solution was injected under the membrane with a syringe to make the nanocarbon film fully contact with the solution, and a laser with a wavelength of 450 nm (power 300 mW) was used to scan the nanocarbon film (scanning rate 200 mm / s) to induce the reduction of GO to graphene, while controlling the laser scanning path to achieve graphene patterning;

[0125] 3) Suspension preparation of patterned nanocarbon films;

[0126] The patterned nano-carbon film obtained in step 2) is further evaporated for 25 minutes, and the solution under the film is pumped away, so that the nano-carbon film is separated from the solution; and the nano-carbon film is further dried at 60° C. for 30 minutes to obtain a suspended nano-carbon film;

[0127] After the nanocarbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned suspended nanocarbon film.

[0128] Comparative Example 2

[0129] A method for preparing a patterned suspended nanocarbon film by laser induction comprises the following steps:

[0130] 1) Preparation of high absorbance GO multi-component solution:

[0131] Prepare a high absorbance nano-carbon-based multi-component composite solution according to the method described in Example 1;

[0132] 2)Interface self-assembly of nanocarbon films and their laser-induced patterning;

[0133] The high-absorbance GO multi-component solution was put into a beaker, stainless steel cup or other container, and placed in a vacuum oven at 60°C and 0.1MPa to evaporate GO to self-assemble into a film at the interface between the solution and the air. When the film was visible to the naked eye, evaporation was continued for 40 minutes to obtain a 130nm thick self-assembled nano-carbon film. A laser with a wavelength of 450nm (power 300mW) was scanned on the nano-carbon film (scanning rate of 200mm / s) to induce the reduction of GO to graphene, resulting in the film being ablated and damaged.

[0134] Comparative Example 3

[0135] A method for preparing a patterned nanocarbon film by laser induction comprises the following steps:

[0136] 1) Preparation of high absorbance nano-carbon-based multi-component compound solution:

[0137] Prepare a high absorbance nano-carbon-based multi-component composite solution according to the method described in Example 1;

[0138] 2) Preparation of nanocarbon films and their laser-induced patterning;

[0139] The highly absorbent nano-carbon-based multi-component composite solution is uniformly coated on a clean glass plate, and placed in a vacuum oven at 60° C. and 0.1 MPa for evaporation to obtain a nano-carbon film (average thickness of 130 nm); a laser with a wavelength of 450 nm (power of 300 mW) is used to scan the nano-carbon film (scanning rate of 200 mm / s) to induce reduction of GO to graphene, and the laser scanning path is controlled (same as in Example 1) to achieve graphene patterning;

[0140] 3) Preparation of patterned nanocarbon-based films;

[0141] After the nano-carbon film was removed, it was placed in hydrogen iodide vapor at 80°C for further reduction for 6 hours, and then vacuum dried at 130°C for 10 hours to obtain a patterned nano-carbon-based film.

[0142] The photo of GO after film formation at the gas-liquid interface in Example 1 of the present invention is as follows Figure 1 As shown. Figure 1 It can be seen that after the high absorbance nano-carbon-based multi-component composite solution prepared by the present invention was self-assembled at 60°C for 10 minutes, the formation of a complete nano-carbon film was clearly observed, indicating that the high absorbance nano-carbon-based multi-component composite solution of the present invention has good interface film-forming ability.

[0143] The UV-visible absorption spectra of the high absorbance nano-carbon-based composite solution and the ordinary GO composite solution prepared in Example 1 of the present invention and Comparative Example 1 are as follows: Figure 2 As shown. Figure 2 It can be seen that the high-absorbency GO multi-component compound solution prepared in the present invention has a higher absorbance, which is beneficial to the improvement of the quality of laser-induced reduced graphene.

[0144] The patterned films obtained in Example 1 of the present invention and Comparative Examples 2 and 3 are respectively as follows: Figure 3 As shown in (a), (b), and (c), it can be seen that the laser induced patterning process of the present invention can realize the control of the laser reduction process of GO and promote the preparation of complete, suspended patterned nanocarbon material films.

[0145] The Raman spectra of the films obtained in Example 1 and Comparative Example 1 are as follows: Figure 4 As shown. Figure 4It can be seen that the G peak intensity of the film obtained by the present invention is significantly higher than that of the D peak. Compared with ordinary GO subjected to laser induced reduction, the value of D peak intensity / G peak intensity is smaller (0.34), the degree of defects is lower, and the quality is higher.

[0146] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for preparing a patterned suspended nanocarbon-based film by laser induction, characterized in that: The steps include: 1) adding a light-absorbing nano-carbon material to an alcohol-water solution of graphene oxide, and ultrasonically treating the solution to obtain a nano-carbon-based multi-component composite solution; 2) adding a nano-carbon-based multi-component composite solution into a container and evaporating it to form a self-assembled nano-carbon film; continuing to inject the nano-carbon-based multi-component composite solution under the obtained self-assembled nano-carbon film until the obtained film is fully in contact with the multi-component composite solution; and then performing laser scanning on the nano-carbon film according to the designed scanning path to obtain a patterned nano-carbon-based film; 3) continuing to subject the obtained patterned nano-carbon-based film to an evaporation treatment, and extracting the solution under the film to separate the film from the solution, and drying to obtain a patterned nano-carbon film suspended on the inner wall of the container; Finally, the obtained patterned nano-carbon film is removed, subjected to a heating reduction reaction, and dried to obtain the patterned suspended nano-carbon-based film.

2. The method according to claim 1, characterized in that The light-absorbing nano-carbon material is one or more of carboxylated carbon nanotubes, carboxylated fullerenes, and acidified nano-carbon black.

3. The method according to claim 1, characterized in that The mass ratio of the introduced light-absorbing nano-carbon material to graphene oxide is 1 to 6:

100.

4. The method according to claim 1, characterized in that The thickness of the self-assembled nano-carbon film is 50nm-2μm.

5. The method according to claim 1, characterized in that The evaporation step adopts heating or vacuum conditions, wherein the heating temperature is 40-70° C. and the vacuum condition is below 0.085 MPa.

6. The method according to claim 1, characterized in that The laser scanning step uses a laser in the ultraviolet-visible light band with a wavelength of 200 to 700 nm; a laser power of 200 to 400 mW; and a scanning rate of 20 to 380 mm / s.

7. The method according to claim 1, characterized in that Step 3) The evaporation treatment time is 20 to 30 minutes.

8. The method according to claim 1, characterized in that Step 3) The heating reduction step adopts a reducing atmosphere; the heating temperature adopted is 70-90° C. and the time is 4-8 hours.

9. The method according to claim 1, characterized in that: Step 3) The drying step adopts heating and vacuum conditions.

10. The patterned suspended nanocarbon-based film prepared by the method according to any one of claims 1 to 9.

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