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We present an efficient method for easy tuning of optical and electrophysical parameters of macroscopic objects formed from single-wall carbon nanotubes (SWCNTs). We have developed a unique step-by-step doping procedure by filling the SWCNT inner channels with acceptors and donors in gaseous conditions. The main parameter that tailors the film properties is the dopant concentration in the SWCNT channels varied through the gaseous filling time. The ambient oxygen impact on the doping level has been measured and analyzed for all considered SWCNT objects. Our approach provides a predictable shift of Fermi level position in the range of 0.1−0.9 eV and the optical band gap edge value between 0.4 and 1.1 eV. The tuning method was applied to optimize the thermopower performance of SWCNT films. We have measured the maximum possible values of the power factor and thermoelectric coefficient and studied the stability of these parameters in the air for studied samples. On the basis of the revealed relation between thermopower and sheet resistance, we propose a general approach for characterization of conducting CNT macro-objects, which we call the "doping map" plotting. This empirical method allows to predict stable, maximum, or optimal values for the transport, thermopower, and optical characteristics of materials in the air. Our findings are prospective for prediction and tailoring of SWNT-containing materials properties used in such technological applications, as electrochemical, sensor, solar cell, or thermoelectric electrode materials.

Metastable modification of MoS2 (1T) is widely recognized as a hopeful non‐precious electrocatalyst in hydrogen production. This paper describes an approach to impart a superambient temperature stability to 1T‐MoS2 by incorporating it in 2D hybrid architecture with cationic monomolecular phenanthrolinium (PhenH+) hydrate layers. The atomic structure and bonding interactions of the assembled architecture revealed by PXRD, TEM, XPS, Raman and UV‐Vis spectroscopy data coupled with DFT calculations and quantum theory of atoms in molecules (QTAIM) analysis suggest that the 1T‐MoS2 sheets are involved in strong bonding with the PhenH‐H2O layers. This results in a highly stable layered system, which is kept intact in 0.5 M sulfuric acid electrolyte and tolerates superambient temperature heating. As compared with pure 1T‐MoS2, the compound with a phenanthroline interlayer provides greater activity and better current‐voltage efficiency in electrocatalytic hydrogen evolution after heating treatment owing to stabilization of the 1T phase. The obtained results could be useful for the design of novel electrocatalytic devices exploiting 1T‐MoS2 modification.

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