Sn-Pb Hybrid Nanoparticle Decorated Mesoporous Carbon for Sensitive Stripping Detection of Cd (II)

Abstract

Novel Sn-Pb hybrid nanoparticle decorated mesoporous carbon (MPC) was successfully prepared on a glassy carbon electrode (GCE) and used for the anodic stripping measurements of Cd(II) via square wave Voltammetry. In the presence of MPC, the properties of Sn-Pb were dramatically improved including the ability of electron transfer, particle size and hydrophilicity, which played a significant role in achieving more preferable analytical performances of Cd(II) with Sn-Pb based sensor. After all the experimental parameters involved were carefully optimized, the proposed Sn-Pb/MPC based sensor was applied to the stripping determination of Cd(II), showing the best electrochemical behaviors by comparison with Sn, Pb and Sn-Pb modified electrodes. The synergic effect between Sn-Pb and MPC was believed to be the major factor leading to such improved electrochemical properties of Sn-Pb/MPC based sensor for Cd(II) analysis. In the concentration range of 0-140 μg L −1 , the linear analytical curve for Cd(II) was achieved with correlation coefficient and detection limit calculated to be 0.9996 and 0.36 μg L −1 (S/N = 3), respectively. By using the standard addition method, Cd(II) ion in river samples was successfully determined with satisfactory recoveries higher than 100%. These results suggest that the proposed method can be applied as a simple, efficient alternative to monitor the heavy metals in water samples, compared with ICP based techniques.

Recent Trends on Electrochemical Sensors Based on Ordered Mesoporous Carbon

“…Due to the electronic conductivity of OMC, the redox-active species can be involved in mediated electrocatalytic schemes in their immobilized form (contrary to non-conducting mesoporous hosts, such as silica-based nanomaterials, for which a certain physical mobility of mediators is necessary to get high sensitivity [ 135 , 136 ], except in case of charge transfer by electron hopping [ 137 , 138 ]). Probably the most widely-used approach is the immobilization of noble metal catalysts in the form of nanoparticles (NPs) or electrogenerated deposits [ 128 , 132 , 134 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 , 154 , 155 ] (or even bimetallic NPs [ 156 , 157 ]), which can be formed by either impregnation of metal precursors and subsequent reduction or from nanoparticles suspensions or slurries, or other NPs/deposits (metal oxides or hydroxides, metal sulfides, etc. [ 106 , 158 , 159 , 160 , 161 , 162 , 163 , 164 , 165 , 166 , 167 , 168 , 169 , 170 , 171 , …”

“…The electrochemical sensors based on functionalized OMC [ 24 , 26 , 49 , 50 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 , 154 , 155 , 156 , 157 , 158 , 159 ...…”