Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash 1 3 4 5 6 7 8 9 10 1 2 13 14 15 16 17 18 19 20 21 22 23 24 25 2 6 45 46 47 48 49 50[.]
RINP 583 No of Pages 7, Model 5G 23 February 2017 Results in Physics xxx (2017) xxx–xxx Contents lists available at ScienceDirect Results in Physics journal homepage: www.journals.elsevier.com/results-in-physics Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Ali Jabbar Abed Al-Nidawi a, Khamirul Amin Matori a,b,⇑, Azmi Zakaria a, Mohd Hafiz Mohd Zaid a,b 10 2 13 14 15 16 17 18 19 20 21 22 23 24 25 a b Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia Materials Synthesis and Characterization Laboratory, Institute of Advanced Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia a r t i c l e i n f o Article history: Received 26 January 2017 Received in revised form 14 February 2017 Accepted 15 February 2017 Available online xxxx Keywords: Rice husk Manganese dioxide Glass Zinc silicate Sintering Optical properties a b s t r a c t In this study, an investigation was conducted to explore and synthesize silicate (SiO2) glass from waste rice husk ash (RHA) MnO2 doped zinc silicate glasses with chemical formula [(ZnO)55 + (WRHA)45]100-X[MnO2]X, (where X = 0, 1, and wt%) was prepared by conventional melt quenching technique The glass samples were characterized using energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, and ultraviolet–visible (UV–Vis) spectroscopy The results revealed that by increasing the concentration of MnO2, the color of glass samples changed from colorless to brown and the density of glass increased XRD results showed that a broad halo peak which centered on the low angle (2h = 30°) indicated the amorphous nature of the glass FTIR results showed basic structural units of Si-O-Si in non-bridging oxygen, Si-O and Mn-O in the glass network FESEM result showed a decreasing porosity with an increasing MnO2 content, which was attributed to the Mn ions resort to occupy interstitial sites inside the pores of glass Besides, the absorption intensity of glass increased and the band gap value decreased with increasing the MnO2 percentage In this synthesized glass system of MnO2 doped zinc silicate glasses using RHA as a source of silica, the MnO2 affect most of the properties of the glass system under investigation Ó 2017 Published by Elsevier B.V This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/) 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Introduction 47 Rice husk (RH) is one of the agricultural waste materials that received high attention because of its high amount of silica content Generally, in Malaysia for each 1000 kg of paddy milled, 220 kg (22%) of rice husk will be produced The subsequent burning of the rice husk will generate about 55 kg (25%) of rice husk ash (RHA) [1] RHA have many good properties such as high porosity, high external surface area, lightweight, and high in silica content inform of amorphous materials (87–97%) and a few metallic impurities [2,3] Rice husk is an agricultural waste material that is renewable and has low bulk density Unfortunately, this waste is left to rot slowly in the field or burnt in an open space Many suggest that recycling of the waste is the best way compared to these unsafe disposals procedure several advantages such as resources and energy saving, reduces incineration and helps in protecting 48 49 50 51 52 53 54 55 56 57 58 59 60 ⇑ Corresponding author at: Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia E-mail addresses: alnedaweali@yahoo.com (A.J.A Al-Nidawi), khamirul@upm edu.my (K.A Matori), azmizak@upm.edu.my (A Zakaria), mhmzaid@gmail.com (M H.M Zaid) the environment [4–6] Nowadays, various researchers have done many works toward utilizations of the waste materials in various industries and as an additive in manufacturing some products [7] Specifically, RHA had been used for development of advanced materials and utilization in many areas Different processing techniques and treatments were employed and effect of various parameters were studied [8,9] Currently, a considerable amount of literature has been published on the use of glass in a wide range of applications in many industries such as automotive, aerospace, electrical, electronic and telecommunication Therefore, intensive research has been carried out in order to improve the properties of the glass, reduce the cost of the material and at the same lower the fabrication cost These motivate researchers to developed new fabrication techniques and utilization of waste materials for better wealth and clean environment Therefore, the aforementioned objectives could be achieved using RH, which is available and abundant and will definitely lower the cost of final products In 2011, Ruangtaweep and coworkers fabricate a glass using 55SiO2 from RHA with the different formula of 20 Na2O, 13 B2O3, 6.3 CaO, 1.0 Al2O3, 0.2 Sb2O3, and 4.5 BaO by melt quenching method at 1100 °C The results of the study indicated that the density of glass derived from RHA is larger than pure SiO2 The results http://dx.doi.org/10.1016/j.rinp.2017.02.020 2211-3797/Ó 2017 Published by Elsevier B.V This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx Temperature °C hours 900 °C hour 500 °C Room temperature Time (Hours) Fig Heating circle for burning rice husk Table Chemical composition of WRHA 84 85 86 87 Percentage by weight SiO2 P2O5 K2O CaO Na2O MgO SO3 Fe2O3 MnO ZnO CuO Rb2O SrO 94.34% 1.86% 1.35% 0.93% 0.70% 0.44% 0.22% 0.07% 0.06% 0.03% 37 PPM 21 PPM 19 PPM further confirmed that the RHA could be used for color glass production [10] Insiripong et al (2013) synthesized a glass material using high purity Na2CO3, B2O3, Al2O3, CaO, BaO, Sb2O3, and SiO2 from RHA In this research, the RH was sintered at 1000 °C and use as a SiO2 source for glass production The physical properties 88 Experimental work 102 Preparation of white rice husk ash 103 The rice husk used in this research was obtained from Tanjung Karang, Selangor, Malaysia To prepare the white RHA, the husks was thoroughly washed with tap water up to three times to remove adhering soil and dust Later the husk was rinsed with distilled water to remove dirt and aqueous soluble substances by repeated stirring and decanting until the aqueous wash turned clear The cleaned RH was then dried in an oven at 100 °C for 24 h The RH samples were later transferred into an electric furnace for a double stage heating process at 500 °C for h and 900 °C for h The burnt samples could cool to room temperature as seen in the temperature cycle curve in Fig 104 Preparation of ZnO-WRHA glasses 115 The pure powder of ZnO was mixed with WRHA The mixture was doped with MnO2 in different ratio (X = 0, 1, 3, and wt%) ascribed to the empirical formula [(ZnO)55 + (WRHA)45]100-X[MnO2]X Dried milling process was carried out on the mixture for 20 h to get homogenous powder Each batch of the samples was placed in an alumina crucible and melted in an electrical furnace at 1400 °C for h The melts samples were then 116 S = c r is to b a lite (S iO 2) S (1 ) Intensity (a.u) 83 Components and the absorption peak were examined after doping RHA with different concentration of MnO2 from 0.0 to 1.0 mol% The findings revealed that the color of the glass changes from colorless to brown by a gradual increase of MnO2 concentration Both density and reflective index were also increased with the increasing of MnO2 concentration, largely, due to the altered atomic volume and an atomic mass of the glass [11] The focus of this study is to improve the properties of glasses using white rice husk ash (WRHA) as a source of SiO2 by preparing zinc silicate glasses doped with MnO2 using conventional melt and quenching method The physical, structure and optical properties of MnO2 doped zinc silicate glasses have been characterized to study the effect of various concentrations of MnO2 on the glass samples S S (1 )(2 0 ) S (1 1 ) 20 30 S S S ( 2 )( 2 ) ( ) 40 50 60 S (3 ) 70 80 p o s it i o n ( T h e t a ) Fig XRD analysis for WRHA Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 89 90 91 92 93 94 95 96 97 98 99 100 101 105 106 107 108 109 110 111 112 113 114 117 118 119 120 121 122 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx Fig FTIR result for WRHA 3.3 3.25 (3.25) Density (g/cm3) 3.2 (3.21) (3.17) 3.15 3.1 3.05 2.95 2.9 (2.88) 2.85 MnO2 (wt.%) Fig Density of MnO2 doped ZnO-WRHA glasses 123 124 125 126 127 128 129 130 131 quenched in water to get glass frits After that, un-doped and doped samples were crushed and ground to 63 lm size powder and compacted using a hydraulic press to get pellets of 13 mm diameter and 2 mm thick All the samples were stored in plastic bags for further experimental investigations The density of the glass samples was measured with electronic densitometer MD300S carried out at room temperature Other properties investigated and analyzed using XRD, FTIR, FESEM, and UV–Visible spectroscopy Results and discussion 132 Characterization of WRHA 133 The chemical composition of WRHA sintered at 900 °C for h was analyzed by (EDXRF) and the results are shown in Table As seen in the table, the major constituent of WRHA is SiO2 at 94.34%, while other oxides (P2O5, K2O, CaO, Na2O, MgO, SO3, Fe2O3, MnO, and ZnO) account for the remaining percentage This 134 Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 135 136 137 138 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx w t % w t % w t % undoped 00 Intensity (a.u.) 00 00 00 00 20 30 40 50 60 70 80 P osition (2 T heta) Fig XRD pattern of MnO2 doped ZnO-WRHA glasses 159 result is consistent with previous studies which found the silica contents in WRHA to be 94.3% and 92–97% [12,13] The XRD analysis was done with PANalytical (Philips) X’ Pert Pro PW3050/60 The XRD patterns of the sample are presented in Fig The pattern exhibits a sharp Bragg’s peaks at a low angle region, which is apparent to the crystalline phase of silica after RHA, have been heated to 900 °C The figure also indicated different peaks of crystalline components in the phase of cristobalite crystal (SiO2) with the most intense peak at 22.049° and obviously, the weak peaks at 28.451°, 31.543°, and 36.202°, respectively The major chemical functional groups present in WRHA are identified by the FTIR and the spectra are shows in Fig Looking at the figure, the band at 3037.81 cm1 was due to OH groups and absorbed water [14] The predominant absorbance peak at 1606.66 cm1 belonged to H-O-H bending vibration Besides, the band at 1054.85 cm1 is assigned to the (Si-O-Si) asymmetry stretching vibrations [15] Finally, there are two sharp bands at 783.22 and 441.85 cm1 assigned to Si-O-Si symmetric stretching and bending vibration respectively The results of the FTIR confirmed the presence of SiO2 in WRHA, which agreed well with the XRD analysis 160 Properties of MnO2 doped ZnO-WRHA glasses 161 Fig shows the density of ZnO-WRHA glasses at different concentration of MnO2 (0, 1, and wt%) The results in the figure showed that the density of the ZnO-WRHA glass increased from 2.885 to 3.253 g/cm3 with increased of MnO2 at 0, 1, and wt % This increased in density is related to the atomic mass of Mn (54.938 a.m.u) which is heavier when compared with other elements presence in the WRHA sample such as Si (28.086 a.m.u), Na (22.989 a.m.u), and Ca (40.078 a.m.u) [16] In addition, other researchers related this development to the figuration of the new linkages inside the glass sample [17] X-ray diffraction (XRD) patterns for all ZnO-WRHA glasses system at various percentages of MnO2 is shown in Fig From the spectra, there is no strong sharp peak but one a broad halo peak in the pattern of the un-doped and MnO2 doped ZnO-WRHA based 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 162 163 164 165 166 167 168 169 170 171 172 173 174 glass samples The broad diffuse is around low angle 30° in entire glasses samples, which reflected glass or amorphous nature of the samples In addition, the glass under investigation has a long-range structural disorder The structure of all the glasses samples was determined with the aid of FESEM as shown in Fig The results revealed the presence of fine pores on the ZnO-WRHA glass in an undoped sample Despite the absence of a particular form of grain after doped, but in general, the surface morphology shows a decrease in the number of pores with increasing the percentage of MnO2 As seen in the microstructural image of the samples prepared at different percentage of MnO2, the Mn resort to occupy interstitial sites within the structure of the glass The lattice constant of glass increased slightly with increasing concentration of MnO2, which leads to increase of the degree of agglomeration that can be observed by comparing the surface morphology in Fig 6(a-d) [18] The spectrums from FTIR results are shown in Fig and it was analyzed and compared with the relative information in the literature [19,20] The effective range of the spectrum observed from 400 to 1250 cm1, with the prominent band at 902.4 cm1 ascribed to Si-O-Si stretching in non-bridging oxygen [21] This peak indicates the presence of SiO4 in the sample The result from FTIR is in good agreement with the result of XRD spectroscopy, which revealed an amorphous phase for the entire glass samples On the other hand, the peak at 1200–4000 cm1 was clearly due to the presence of water, hydroxyl, Si-OH or similar groups [22] Therefore, the bands at 1555.85 could indicate Si-O or Mn-O, which gives rise to an IR peak The peak at 3032.79 could be attributed present H-bonding of H2O Furthermore, Zhang and Jahanshahi suggests that this band might ascribe to absorb moisture from the air [23] The analysis of the optical absorption spectra is useful to locate the width to the band gap in order to identify the substance from the spectrum emitted or absorbance light in the material [24] The optical absorbance of the MnO2 doped zinc silicate glasses is shown in Fig As shown from the absorption curve, there is no big sharp absorption edge, which dictates the presence glass phase From the absorption curve, it can be observed that with increase of Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx A B C D Fig FESEM image of MnO2 doped ZnO-WRHA glasses, (a) undoped (b) wt% (c) wt% and (d) wt% 213 214 215 216 217 218 219 MnO2 concentration, the absorption intensity increased and the intensive absorption, which can be seen in the range of 250–350 nm [25] The optical band gap in the amorphous system is closely related to the energy gap between the valence band and conduction band In the amorphous system, the condition band affects by the new glass formation anions The relation between absorption coeffi- cient and extinction coefficient (K) in the equation below determines the experimental value of optical band gap: K ẳ ak=4p 3:1ị From the plot of the extinction coefficient versus hv, the experimental value for the optical band gap was extrapolating from the linear region of the extinction coefficient (K) to zero After Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 220 221 222 224 225 226 227 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx Fig FTIR spectra of MnO2 doped ZnO-WRHA glasses 1.2 Absorbance (a.u.) 0.8 0.6 wt % 0.4 wt % 250 350 450 550 650 wavelength (nm) Fig Absorption spectra of MnO2 doped ZnO-WRHA glasses 230 231 232 233 Conclusions 238 A series of ZnO-WRHA glasses doped MnO2 were prepared by melt quenching technique with aim of studying the effect of various concentration of MnO2 on the physical, structure and optical properties of the glass samples Upon density measurement by Archimedes’ principle, the density increased from 2.885 to 3.253 g/cm3 with increased in the percentage of MnO2 from 0, 1, and wt% The XRD confirmed the formation of the amorphous glassy phase in the samples The results from FTIR agreed with the XRD pattern with a band at 902.4 cm1, which was attributed to Si-O-Si stretching in non-bridging oxygen’s The FESEM images shows decrease trend in the number of pores with increasing percentage of MnO2 and glassy phase of samples From the absorption curve, it can be observed with the increasing concentration of MnO2, the absorption intensity increased and intensive absorption can be seen in the range from 250 to 350 nm From the results of the UV–visible spectroscopy, the optical band gap value decreased 239 235 236 237 wt % 229 234 undoped 0.2 228 Fig According to the literature review, with an increase in MnO2 in the glass network might lead to the breakdown of SiO4 network consequence to product non-bridging oxygen, whereby the electrons were loosely bonded to NBO’s than BO’s [26] compiled all the obtained Eg values in Table 2, a good agreement between the Eg in the differential curve with the value in n = 3/2 can be observed Hence, the obtained experimental value of the optical band gap arises in the glass system by direct forbidden transitions The optical band gap value decreased from 4.70 to 4.21 with increasing the MnO2 percentage as can be seen in the Table Variation of Eopt for MnO2 doped ZnO-WRHA glasses Optical band gap Eopt (eV) Undoped wt% wt% wt% Eopt(experimental) Eopt from differential curve n = in the indirect allowed transition n = in the indirect forbidden transition n = 1/2 in the direct allowed transition n = 3/2 in the direct forbidden transition 4.788 ± 0.03 4.95 ± 0.03 4.871 ± 0.03 4.08 ± 0.03 5.16 ± 0.03 4.7 ± 0.03 5.02 ± 0.03 4.84 ± 0.03 4.42 ± 0.03 4.47 ± 0.03 5.14 ± 0.03 4.61 ± 0.03 4.50 ± 0.03 4.65 ± 0.03 3.93 ± 0.03 3.41 ± 0.03 5.09 ± 0.03 4.42 ± 0.03 4.37 ± 0.03 4.55 ± 0.03 3.93 ± 0.03 3.29 ± 0.03 5.05 ± 0.03 4.21 ± 0.03 Please cite this article in press as: Al-Nidawi AJA et al Effect of MnO2 doped on physical, structure and optical properties of zinc silicate glasses from waste rice husk ash Results Phys (2017), http://dx.doi.org/10.1016/j.rinp.2017.02.020 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 RINP 583 No of Pages 7, Model 5G 23 February 2017 A.J.A Al-Nidawi et al / Results in Physics xxx (2017) xxx–xxx Fig Energy band gap at n = 3/2 for MnO2 doped ZnO-WRHA glasses 257 from 4.70 to 4.21 with increasing of MnO2 percentage due to the defect MnO2 in the samples and product non-bridging oxygen’s, which leads to the breakdown of SiO4 network 258 Acknowledgement 259 261 The authors gratefully acknowledge the financial support for this study from the Malaysian Ministry of Higher Education (MOHE) through the Fundamental Research Grant Scheme 262 References 255 256 260 263 264 265 266 267 268 269 270 271 272 273 274 [1] Fattah MY, Rahil FH, Al-Soudany KY J Civil Eng Urban 2013;3:12–8 [2] Matori KA, Haslinawati MM, Wahab ZA, Sidek HAA, Ban TK, Ghani WAWAK MASAUM J Basic Appl Sci 2009;1:512–5 [3] Della VP, Kühn I, Hotza D Mater Lett 2002;57:818–21 [4] Soltani N, Bahrami A, Pech-Canul MI, González LA Chem Eng J 2015;264:899–935 [5] Ahmaruzzaman M Prog Energy Combust Sci 2010;36:327–63 [6] Chen SY, Chou PF, Chan WK, Lin HM Ceram Int 2017;43:2239–45 [7] Sinyoung S, 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