NOVELTY - A hybrid composite nanomaterial comprises a hydrotalcite like layered double hydroxide compound provided with one or more lanthanide elements inserted into the 2D layers and one or more organic compounds, having at least one of the functional group, in its oxidized or reduced form or salts, from among the following: hydroxyl, carbonyl, carboxyl, amino, phosphate, sulfhydryl and pertain non exclusively to the class of enzymes or proteins, porphyrin or cannabis, intercalated between them.    USE - The hybrid composite nanomaterial is useful in manufacturing an organic-inorganic solar cell, for producing porous co-axial host matrices, and for application as sensor or inhibitor or cure materials in medical field (all claimed).    ADVANTAGE - The hybrid composite nanomaterial has simple production steps and cost efficient.    DETAILED DESCRIPTION - A hybrid composite nanomaterial comprises a hydrotalcite like layered double hydroxide compound provided with one or more lanthanide elements inserted into the 2D layers and one or more organic compounds, having at least one of the functional group, in its oxidized or reduced form or salts, from among the following: hydroxyl (R-OH), carbonyl (R1-C=O-R2), carboxyl (RCOOH), amino (RNH2), phosphate (ROP(OH)2=O), sulfhydryl (R-SH) and pertain non exclusively to the class of enzymes or proteins, porphyrin or cannabis, intercalated between them. INDEPENDENT CLAIMS are included for:    (1) a method for the production of a composite nanomaterial, the method providing a single step one-pot synthesis of insertion of one or more lanthanide elements into the 2D layers of a hydrotalcite like layered double hydroxide compound via a self assembly process occurring in the presence of chelating organic compounds under hydrothermal conditions in a sealed container;    (2) an organic-inorganic solar cell comprising the composite nanomaterial combined with electrospun aligned functionalized electron transporting inorganic materials inserted into a conducting polymer matrix; and    (3) a method for the production of a layered structure copper indium gallium selenide ((CuInGaSe2), CIGS) replica material which is provided with the intermediate structure: (Cu2+xZn2+1-xIn3+yAl3+3-y-zGa3+z(HSe)4-8)+3(acceptor-n+(SeO42-)m)(3/(n+2m)) by hydrothermal synthesis with HSe- as major anionic species, generated in situ via sulfur dioxide (SO2) and H3/HCl(g) bubbling in the presence of aluminum (Al+) and sodium (Na+) ions, where consumption of 2D substituted Al3+ of a hybrid composite nanomaterial to alumina is controlled by bubbling of SO2 gas into the reaction chamber for the in situ produced Se to react with Al3+ such that the layered structure or CIGS replica material is rendered with its default p-type character; and where by a possible simultaneous re-addition of In3+ along with the gas bubbling; a submission of the solution mixture to a second step of high temperature, pressure and time (T, P, t) conditions, where the Al deficient compound is exposed to indium/sodium ions, such that the layered structure CIGS replica material is provided with a n-type character.