Adsorption of heterobifunctional 4-nitrophenol on the Ge(100)-2 × 1 surface

Abstract

We report the adsorption chemistry of a heterobifunctional molecule, 4-nitrophenol, on the Ge(100)-2 × 1 surface. X-ray photoelectron and infrared spectroscopy experiments and density functional theory calculations were used to determine the adsorption products. The results show that 4-nitrophenol reacts with the Ge surface through either one or both of the-OH or-NO 2 functionalities. It was found that the fraction of dually and singly tethered adsorbates varies according to reaction conditions: namely, singly tethered adsorbates are favored at higher adsorbate coverages and lower adsorption temperatures. These variations are explained by a two-step adsorption mechanism for 4-nitrophenol, in which geometrical limitations of the adsorbates on the surface affect the product distribution.

Catalytic Reduction of 4-Nitrophenol to 4-Aminophenol Using Ag@α-Ti(HPO4)2·H2O: Experimental and Computational Studies

“…On the basis of the results of the DFT calculation, binding of 4-NP or 4-NP – occurs mainly through −NO 2 , −OH, or both groups. Previous DFT studies on 4-NP also confirm that binding occurs through −NO 2 , −OH, or both functional groups to various metal/semiconductor surfaces. − …”

Cellulose-g-tetraethylenepentamine Dual-function Imprinted Polymers Selectively and Effectively Adsorb and Remove 4-Nitrophenol and Cr(VI)

“…8d) and after the adsorption (Fig. 8e) was the addition of the 406.26 eV peak of the -NO 2 group (Shong et al 2016). A minor difference also existed, which comprised of the observation that the ratio of N-H bonds was 6% higher after the adsorption (Fig.…”

Cellulose-g-tetraethylenepentamine dual-function imprinted polymers selectively and effectively adsorb and remove 4-nitrophenol and Cr(VI)

“…8d) and C 1s (Fig. 8e), in addition to the O 1s spectrum of C-TEPA-MIP after 4-NP adsorption, there is an additional peak of N-O-H bond at 533.7 eV, which is the free hydroxyl group of 4-NP assigned to a single NO 2 cycloaddition product (Shong et al 2016) S2. The values of the specific surface areas of C-TEPA-MIP, C-TEPA-MIP adsorbing 4-NP and C-TEPA-MIP adsorbing Cr(VI) were 118.090 m 2 /g, 107.711 m 2 /g and 171.734 m 2 /g.…”

“…In the adsorption of 4-NP, the only major difference observed between XPS data of the adsorbent before the adsorption and after it was the addition of the 406.3 eV peak of the -NO 2 group (Shong et al 2016). A minor difference also existed, which comprised of the observation that the ratio of N-H bonds was 6% higher after the adsorption compared to that observed before the adsorption, indicating that the adsorption of 4-NP onto the adsorbent occurred through imprinting and hydrogen bonding between N and H. In the spectra of O 1s (Fig.…”