AFM study of morphological changes associated with electrochemical solid–solid transformation of three-dimensional crystals of TCNQ to metal derivatives (metal = Cu, Co, Ni; TCNQ = tetracyanoquinodimethane)

Metal–Molybdenum Sulfide Nanosheet Arrays Prepared by Anion Exchange as Catalysts for Hydrogen Evolution

“…In the FTIR spectrum of the NiTCNQ nanowire arrays (Figure S4b, Supporting Information), the corresponding characteristic peaks were located at 820, 1509, 2177, and 2211 cm −1 . These results are similar to the reported results for M n+ [TCNQ] n (M = Ni 2+ , Fe 2+ , Co 2+ , and Cu + ) analogs, [ 22–27 ] confirming the presence of TCNQ − anions in the CuTCNQ and NiTCNQ nanowire arrays. After the anion‐exchange treatment by the (NH 4 ) 2 MoS 4 solution, the characteristic Raman and FTIR peaks of the CuTCNQ and NiTCNQ nanowire arrays disappeared (Figure S3c,d and S4c,d, Supporting Information), indicating that the TCNQ − anions were successfully replaced by the MoS 4 2− anions.…”

“…Transition metal–tetracyanoquinodimethane (M n+ [TCNQ] n , M = Ni 2+ , Cu + , Fe 2+ , and Co 2+ ) charge‐transfer complexes have received substantial interest over the past decades, because they can be synthesized easily and fabricated as micro/nanostructures such as nanorod or nanowire arrays. [ 22–27 ] Therefore, the M n+ [TCNQ] n complexes with well‐controlled morphologies are the potential intermediates for the synthesis of self‐supported M–MoS x ‐based catalysts with nanoarray morphologies. In this study, we demonstrate our recent efforts toward the development of CuMoS x and NiMoS x nanosheet arrays as catalysts for the HER on copper (CF) and nickel foams (NF), respectively.…”

Cation and anion electrochemically assisted solid-state transformations of malachite green

“…The solid-state electrochemistry of MG in contact with aqueous NaCl can be viewed within the context of redox-driven solid state transformations. Cation insertion to form M-TCNQs has been extensively studied by Bond et al, 39,40,[54][55][56] while examples of anion insertion on heteropolymetallic clusters bearing ferrocenyl groups [57][58][59] and bisferrocenylfunctionalized pseudopeptides 32 have been reported. Finally, proton insertion/deinsertion is involved in the solid-state electrochemistry of several organic compounds such as azobenzene, 5 2-mercaptobenzoxazole, 6 and dyes, 26 among others.…”

“…There are, however, relatively few studies in which the structural changes occurring in these processes are studied at the nanoscopic scale, and the production mode of the solid product appears to be determined by different factors so that the new solid can segregate forming inclusions in the parent solid phase, 36 yield bilayered structures 37,38 or form new solids, clearly differing in the morphology and crystal size. 39,40 The purpose of the current work is to study both the thermochemical and structural aspects involved in the solid state electrochemistry of malachite green (MG). This is a member of the triphenylmethane dyes and is widely used as a dye in photoelectrochemical applications [41][42][43] Electrode modification was carried out by lightly pressing 2 mm diameter graphite bars (Faber-Castell, HS pencil leads) over a thin layer of MG powdered on the plane surface of an agate mortar.…”

Ion-transfer- and photo-electrochemistry at liquid|liquid|solid electrode triple phase boundary junctions: perspectives

“…16 This work has been developed and exploited, for example for the cation insertion into organic solids such as tetracyanoquinodimethane (TCNQ). 17 Intriguing structures such as nanowires, 18,19 tubules, 20 and crystals 21 have been grown by direct or electro-synthesis. Theoretical models for the analysis of current response data from voltammetric measurements have been proposed.…”