This paper reports that SiO2 is selected to fabricate broadband antireflection (AR) coatings on fused silica substrate by using glancing angle deposition and physical vapour deposition. Through accurate control of t...This paper reports that SiO2 is selected to fabricate broadband antireflection (AR) coatings on fused silica substrate by using glancing angle deposition and physical vapour deposition. Through accurate control of the graded index of the SiO2 layer, transmittance of thc graded broadband AR coating can achieve an average value of 98% across a spectral range of 300-1850 nm. Moreover, a laser-induced damage threshold measurement of the fabricated AR coating is performed by using a one-on-one protocol according to ISOl1254-1, resulting in an average damage threshold of 17.2 J/cm2.展开更多
The traditional single material with two-dimensional (2D) biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited we...The traditional single material with two-dimensional (2D) biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional (3D) biomimetic moth-eye coating with ternary materials (polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p). This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.展开更多
In order to realize ultralow surface reflectance and broadband antireflection effects which common pyramidal textures and antireflection coatings can't achieve in photovoltaic industry,we used low-cost and easy-ma...In order to realize ultralow surface reflectance and broadband antireflection effects which common pyramidal textures and antireflection coatings can't achieve in photovoltaic industry,we used low-cost and easy-made Ag-catalyzed etching techniques to synthesize silicon nanowires(Si NWs) arrays on the substrate of single-crystalline silicon.The dense vertically-aligned Si NWs arrays are fabricated by local oxidation and selective dissolution of Si in etching solution containing Ag catalyst.The Si NWs arrays with 3 μm in depth make reflectance reduce to less than 3% in the range of 400 to 1000 nm while reflectance gradually reached the optimum value with the increasing of etching time.The antireflection of Si NWs arrays are based on indexgraded mechanism:Si NWs arrays on a subwavelength scale strongly scatter incident light and have graded refractive index that enhance the incidence of light in usable wavelength range.However,surface recombination of Si NWs arrays are deteriorated due to numerous dangling bonds and residual Ag particles.展开更多
Femtosecond laser induced periodic surface structures(LIPSSs)are excellent biomimetic iridescent antireflective interfaces.In this work,we demonstrate the feasibility to develop tunable iridescent antireflective surfa...Femtosecond laser induced periodic surface structures(LIPSSs)are excellent biomimetic iridescent antireflective interfaces.In this work,we demonstrate the feasibility to develop tunable iridescent antireflective surfaces via simultaneous synthesis of functional metal-oxide nanomaterials,in situ deposition and hierarchical LIPSSs nanostructuring by means of femtosecond laser ablation(fs-LA)of tungsten(W)and molybdenum(Mo)in air.Adjusting the scanning interval from 1μm to 20μm allows the modulation of particle deposition rates on LIPSSs.Diminishing the scan interval enables a higher particle deposition rate,which facilitates the development of better UV-to-MIR ultrabroadband antireflective surfaces with a less pronounced iridescence.Through comparing the reflectance of hierarchical LIPSSs with different densities of loosely/tightly deposited particles,it is found that the deposited WO_(x)and MoO_(x)particle aggregates have high UV-to-MIR ultrabroadband absorbance,especially extraordinary in the MIR range.Loosely deposited particles which self-assembly into macroporous structures outperform tightly deposited particles for ultrabroadband antireflective applications.The presence of loosely deposited MoO_(x)and WO_(x)particle absorbers can cause up to 80%and 60%enhancement of antireflectance performances as compared to the tightly particle deposited LIPSSs samples.One stone of"fs-LA technique"with three birds of(particle generation,in situ deposition and LIPSS hierarchical nanostructuring)presented in this work opens up new opportunities to tune the reflectance and iridescence of metallic surfaces.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 10804060)Higher Educational Science and Technology Program of Shandong Province of China (Grant No. J08LI05)
文摘This paper reports that SiO2 is selected to fabricate broadband antireflection (AR) coatings on fused silica substrate by using glancing angle deposition and physical vapour deposition. Through accurate control of the graded index of the SiO2 layer, transmittance of thc graded broadband AR coating can achieve an average value of 98% across a spectral range of 300-1850 nm. Moreover, a laser-induced damage threshold measurement of the fabricated AR coating is performed by using a one-on-one protocol according to ISOl1254-1, resulting in an average damage threshold of 17.2 J/cm2.
基金This work was supported by the National Natural Science Foundation of China (Nos. 21401079, 21501069, and 21671081), Fundamental Research Funds for the Central Universities (No. JUSRP51626B), and Natural Science Foundation of Jiangsu Province (Nos. BK20140158 and BK20161128).
文摘The traditional single material with two-dimensional (2D) biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional (3D) biomimetic moth-eye coating with ternary materials (polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p). This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.
基金partly supported by Natural Science Foundation of China (No.60876045)Shanghai Leading Basic Research Pro ject (No.09JC1405900)+2 种基金Shanghai Leading Academic Discipline Pro ject (No.S30105)R&D Foundation of SHU-SOENs PV Joint Lab (No.SS-E0700601)supported by Analysis and Testing Center of Shanghai University
文摘In order to realize ultralow surface reflectance and broadband antireflection effects which common pyramidal textures and antireflection coatings can't achieve in photovoltaic industry,we used low-cost and easy-made Ag-catalyzed etching techniques to synthesize silicon nanowires(Si NWs) arrays on the substrate of single-crystalline silicon.The dense vertically-aligned Si NWs arrays are fabricated by local oxidation and selective dissolution of Si in etching solution containing Ag catalyst.The Si NWs arrays with 3 μm in depth make reflectance reduce to less than 3% in the range of 400 to 1000 nm while reflectance gradually reached the optimum value with the increasing of etching time.The antireflection of Si NWs arrays are based on indexgraded mechanism:Si NWs arrays on a subwavelength scale strongly scatter incident light and have graded refractive index that enhance the incidence of light in usable wavelength range.However,surface recombination of Si NWs arrays are deteriorated due to numerous dangling bonds and residual Ag particles.
文摘Femtosecond laser induced periodic surface structures(LIPSSs)are excellent biomimetic iridescent antireflective interfaces.In this work,we demonstrate the feasibility to develop tunable iridescent antireflective surfaces via simultaneous synthesis of functional metal-oxide nanomaterials,in situ deposition and hierarchical LIPSSs nanostructuring by means of femtosecond laser ablation(fs-LA)of tungsten(W)and molybdenum(Mo)in air.Adjusting the scanning interval from 1μm to 20μm allows the modulation of particle deposition rates on LIPSSs.Diminishing the scan interval enables a higher particle deposition rate,which facilitates the development of better UV-to-MIR ultrabroadband antireflective surfaces with a less pronounced iridescence.Through comparing the reflectance of hierarchical LIPSSs with different densities of loosely/tightly deposited particles,it is found that the deposited WO_(x)and MoO_(x)particle aggregates have high UV-to-MIR ultrabroadband absorbance,especially extraordinary in the MIR range.Loosely deposited particles which self-assembly into macroporous structures outperform tightly deposited particles for ultrabroadband antireflective applications.The presence of loosely deposited MoO_(x)and WO_(x)particle absorbers can cause up to 80%and 60%enhancement of antireflectance performances as compared to the tightly particle deposited LIPSSs samples.One stone of"fs-LA technique"with three birds of(particle generation,in situ deposition and LIPSS hierarchical nanostructuring)presented in this work opens up new opportunities to tune the reflectance and iridescence of metallic surfaces.