紫外可见近红外光谱法评价太阳能反射涂料

近年来，太阳能反射涂料作为一种对抗“热岛”现象的方法和一种可持续的家用建筑材料，引起了人们的关注。热岛是指城市地区的温度明显高于周围农村地区，建筑物、道路和基础设施取代了大部分自然景观和植被。如下图所示，太阳辐射在近红外区域具有显著的能量。太阳能反射涂料是专门为反射近红外光而设计的，其效率高于一般用途的涂料。因此，这些材料可以用来反射建筑物表面的热量，减少热能，并冷却涂层物体。Application NoteUV-O011 Evaluation of a Solar Reflective PaintMaterial using the V-6702/3Application Note Evaluation of a Solar Reflective Paint Material using the V-670 Intro d uc t ion In recent yea r s， sola r r ef l ective paints h ave attracted attention as a way to combat the ‘heat island' phenomenon and as a sustainable household bu il d i ng mater i al . Heat islands a r e urban areas whe r e the temperature i s signif i cantly hotter than the surround i ng rural areas and occur whe r e build i ngs， roads ， and infrastructure have replaced a majority of the natu r al landscape and vegetation . V-670As shown in F i gure 1， solar radiation h as sig ni f i cant energy in the n ea r IR region. Solar UV-Vis Spect r ophoto m et e r reflect i ve paints are speci f ically designed to ref l ec t NIR light wi th higher ef f ic i e n cy than general usage paints . Therefore， these mate r ials can be used to reflect t h e h eat from the surface of a building， reducing the the r mal energy， and cooling the coated object. Figure 1. A sta n d ar d solar in ten s it y spec t r u m (l ef t) a n d t h e r m a l en ergy re ductio n usin g so l a r r eflecti v e ma t eri a l s (r igh t) This application n ote eva lu ates solar r eflective pa i nts using a V-670 UV-Visible/NIR spectrophotometer with i ntegrating sphere . K e yword s V -670 uv -vi s ibl e/n i r sp ectr o pho t o m eter， U V -Vi si bl e/NIR， Mat e r i al s ， Ne a r-i n frared ， I SN-723 I n t e g ratin g sph e r e， VWCD-790C o l o r d iagno sis， VWS T-774 S o lar /v i si bl e l i gh t me a s ur e m e n t Experimen t al Two aluminum pla t es were painted wit h both a general wate r -based pai n t and a sol a r refl e ct i ve pain t in t wo di ff er e n t colors and d ri ed completely f or 7 days. Figure 2. G r ey a nd red s a mple s p ai n t e d w it h ref le ctive a nd g en er a l p a int. Measurement Range 300-2500 nm Data Interval 1nm UV-Vis Bandwidth 4.0nm NIR Bandwidth 2.0nm Scan speed 1000 nm/min Response Fast Results The diffuse reflectance of the fou r samples was measured and the spect r a are shown in Figure 3. The data illustrate that samples with the solar ref l ective material paint have h i g h er reflectance i n the NIR region than the general water-based paint. Figure 3. Diffus e r efle ctanc e s pect r a of gr ey (l ef t) an d r e d (r i g h t) sam p l es wi t h t he gen er a l w a ter -b a s ed pa i n t (gr e en) and s ol ar ref le c t i v e m a ter i al p a i n t (bl u e). 28600 Mary's Cour t ， E a s to n ， M D 21601US A Using t h e diff u s e r e f lectanc e spect r a， t h e color analysis of b oth paint ma t er i als was per f orm e d wi th th e Color Analysis Program an d t h e r e sults are shown in F i gur e 4. T he data i llu st r ate v e ry similar color posi ti ons for bot h the dif fe r e nt gr e y a n d r e d pai n t samples o n the c h romatici t y d i agram， even though the pain t s have very diffe r ent ref l ectance cha r acteris ti cs. Figure 4. C hro m a t icit y diagr a m. The reflectance values of solar light at t h ree different wavelength ranges was also calculated for the paint samples using the Solar/visible light measu r ement program. The results are shown in Table 1 and indicate that the solar r eflective paint material has h i g h er reflectance values i n all wave l engt h regions， as well as the NIR r egion. Table 1. Calc ul ated va l u e s o f ref l e c t e d so l a r l igh t . Gray Red Solar Reflective Water Paint Solar Reflective Water Paint UV-Vis 24.09 32.19 21.67 17.60 NIR 70.39 26.68 64.98 50.61 UV-Vis/NIR 44.30 29.75 40.53 31.95 JASCO INC. 28600 Mary's Cour t ， E a s to n ， M D 21601US A UASGO