Facile synthesis of porous bismuth–carbon nanocomposites for the sensitive detection of heavy metals

Bismuth doped carbon xerogel nanocomposite incorporated in chitosan matrix for ultrasensitive voltammetric detection of Pb(II) and Cd(II)

“…Recently, CXs were used, with excellent results, as electrode materials for supercapacitors and rechargeable batteries, as efficient catalyst support, as well as adsorbent material and molecular sieve [34]. Supplementary, should be mentioned that the morpho-structural properties of CXs can be easily controlled by changing one or more of the processing parameters [13,34].…”

“…In this context, taking into account the easy preparation, the good chemical and structural characteristics, combined with some peculiar properties such as huge specific surface area, very low density, high porosity and electrical conductivity [13], a homemade carbon xerogel (CX) was investigated as supporting matrix for the preparation of Bi-modified electrodes. Recently, CXs were used, with excellent results, as electrode materials for supercapacitors and rechargeable batteries, as efficient catalyst support, as well as adsorbent material and molecular sieve [34].…”

“…However, the above mentioned methods compared with the electrochemical methods [13,14] are considered more expensive and time-consuming. Besides this, the simplicity, intrinsic sensitivity and high selectivity recommend the electrochemical techniques among the most adequate options for heavy metals detection.…”

Electrochemically Active Thin Carbon Films with Enhanced Adhesion to Silicon Substrates

“…The recorded peak currents (see Figure S4) are proportional to the square-root of the scan rate in the range of 10-100 mV/s, which is the usual behavior of a diffusion-controlled electrode process. Figure 6 compares the cyclic voltammetric responses of a porous carbon xerogel paste electrode (C P PE) as prepared in our previous publication 17 24 , n is the number of electrons involved in the electrochemical reaction, which in this case is equal to one, ν is the scan rate in V/s, F is the faraday constant, R is the universal gas constant and T the absolute temperature. The dimensionless kinetic parameter, ϕ, is first determined using the following analytical equation:…”

“…Thus, considering the well-known fact that silica films on Si substrates show strong film/substrate adhesion due to the formation of siloxane chemical bonds (-Si-O-Si-) 16 , one route to improve the adherence of carbon film on Si substrates is by the incorporation of silica into the carbon matrix. Interestingly, we reported that pyrolyzed organic gels are appealing materials to fabricate electrodes for electrochemical sensors 17 and moreover sol-gel chemistry offers the possibility of mixing the different precursors from carbon and silica at molecular level resulting in homogeneous composite (carbon/silica) hybrid materials 18 . In particular, Song et al…”