A method for producing a nanowire structural element comprising a nanowire array arranged between two cover layers (26a, 26b) to form a cavity structure permeated by the nanowires in a columnar manner, comprising: (a) providing a template film; (b) depositing a first electrically conductive full-surface contiguous cover layer on a first side of the template film; (c) producing a multitude of nanopores in said template film; producing nanowires in said nanopores by filling the nanopores by electrochemical deposition of an electrically conductive material, wherein the nanowires grow inside the nanopores on the first cover layer, and wherein the nanowires have a diameter of less than or equal to 2000 nm; producing a second full-surface contiguous cover layer on the second side of the template film, so as to create a sandwich-like arrangement consisting of the two cover layers (26a, 26b) and the template film permeated by the nanowires; (e) exposing the cavity structure between the two cover layers (26a, 26b) by dissolving the template film and removing the dissolved template material between the two cover layers (26a, 26b), while the two cover layers remain intact; wherein steps and are performed as sub-steps of the same electrochemical deposition process, by continuing the electrochemical deposition process after the nanopores have been completely filled in accordance with sub-step until the second cover layer is completed, by having caps growing on the nanowires on the second side of the template film and the caps growing together to form a flat full-surface contiguous layer and this flat full-surface contiguous layer continuing to grow until the stable second cover layer is completed, so that the nanowires and the second cover layer are grown as an integral structure; or wherein the electrochemical deposition process according to sub-step is continued until caps grow on the nanowires on the second side of the template film and the caps grow together at least partially, and in a further, subsequent deposition process, a full-surface contiguous layer is deposited on top of the caps that have at least partially grown together, with the stable second cover layer being formed from the caps that have at least partially grown together and the full-surface contiguous layer. (a) providing a template film; (b) depositing a first electrically conductive full-surface contiguous cover layer on a first side of the template film; (c) producing a multitude of nanopores in said template film; producing nanowires in said nanopores by filling the nanopores by electrochemical deposition of an electrically conductive material, wherein the nanowires grow inside the nanopores on the first cover layer, and wherein the nanowires have a diameter of less than or equal to 2000 nm; producing a second full-surface contiguous cover layer on the second side of the template film, so as to create a sandwich-like arrangement consisting of the two cover layers (26a, 26b) and the template film permeated by the nanowires; (e) exposing the cavity structure between the two cover layers (26a, 26b) by dissolving the template film and removing the dissolved template material between the two cover layers (26a, 26b), while the two cover layers remain intact; wherein steps and are performed as sub-steps of the same electrochemical deposition process, by continuing the electrochemical deposition process after the nanopores have been completely filled in accordance with sub-step until the second cover layer is completed, by having caps growing on the nanowires on the second side of the template film and the caps growing together to form a flat full-surface contiguous layer and this flat full-surface contiguous layer continuing to grow until the stable second cover layer is completed, so that the nanowires and the second cover layer are grown as an integral structure; or wherein the electrochemical deposition process according to sub-step is continued until caps grow on the nanowires on the second side of the template film and the caps grow together at least partially, and in a further, subsequent deposition process, a full-surface contiguous layer is deposited on top of the caps that have at least partially grown together, with the stable second cover layer being formed from the caps that have at least partially grown together and the full-surface contiguous layer. wherein steps and are performed as sub-steps of the same electrochemical deposition process, by continuing the electrochemical deposition process after the nanopores have been completely filled in accordance with sub-step until the second cover layer is completed, by having caps growing on the nanowires on the second side of the template film and the caps growing together to form a flat full-surface contiguous layer and this flat full-surface contiguous layer continuing to grow until the stable second cover layer is completed, so that the nanowires and the second cover layer are grown as an integral structure; or wherein the electrochemical deposition process according to sub-step is continued until caps grow on the nanowires on the second side of the template film and the caps grow together at least partially, and in a further, subsequent deposition process, a full-surface contiguous layer is deposited on top of the caps that have at least partially grown together, with the stable second cover layer being formed from the caps that have at least partially grown together and the full-surface contiguous layer.