RESUMO
2D-2D lattice engineering route is used to synthesize intimately coupled nanohybrids of layered double hydroxide (LDH) and potassium hexaniobate. The 2D-2D lattice engineering route is based on the electrostatically derived self-assembly of delaminated zinc-chromium-layered double hydroxide (ZC-LDH) nanosheets and potassium hexaniobate (HNb) nanosheets (ZCNb nanohybrids). The 2D-2D lattice-engineered ZCNb nanohybrids display expanded surface area, mesoporous anchored nanosheets network morphology, and intimate coupling between nanosheets. The 2D-2D lattice engineered ZCNb nanohybrids are used for the low temperature operated gas sensor. The ZCNb nanohybrids display outstanding selectivity for the SO2, with the high response of 61.5% compared to pristine ZC-LDH (28.08%) and potassium niobate (8%) at 150 °C. Moreover, ZCNb sensors demonstrate superior response and recovery periods of 6 and 167 s at 150 °C, respectively. This result underscores the exceptional functionality of the ZCNb nanohybrids as efficient SO2 sensors. Moreover, these findings vividly demonstrate that the 2D-2D lattice-engineered ZCNb nanohybrids are quite effective not only in improving the gas sensor activity but also in developing of new type of intimately coupled mesoporous LDH-metal-oxide based hybrid materials.
RESUMO
Nanocrystalline cobalt sulfide thin film electrodes have been deposited on stainless steel substrate using binder-free chemical bath deposition (CBD) method and electrochemical study is performed in 1â¯M KOH electrolyte. Linear sweep voltammetry (LSV) curve shows that cobalt sulfide thin film electrode requires 300â¯mV overpotential (Æ) to reach the current density of 10â¯mAâ¯cm-2. Also, it exhibits Tafel slope of 57â¯mVâ¯decade-1 with stable catalytic activity over 14â¯h. Along with good electrocatalytic oxygen evolution performance, in supercapacitive study it shows specific capacitance of 252.39â¯Fâ¯g-1 at a scan rate of 5â¯mVâ¯s-1. The stability test indicates that cobalt sulfide electrode is stable for 1000 cyclic voltammetry (CV) cycles.