65138 2025 eng 1 8 article Wiley VHC-Verlag 1 -- -- -- The development of thermally stable solid-state proton conductors (SSPCs) is crucial for advancing energy-conversion devices such as proton-exchange membrane fuel cells (PEMFCs). In this work, we report the solvothermal synthesis and characterization of a novel, 1D Cu(I) coordination polymer, {Cu(ADP)0.5(BPY)}n (BAM-5), based on anthracenediylphosphonate (H2ADP) and 4,40 -bipyridine (BPY). Single-crystal X-ray diffraction revealed that BAM-5 crystallizes in the triclinic space group P1 and shows a 1D ladder structure connected by the H2ADP and organic BPY linkers, which is assembled into a 2D layer via O−H···O hydrogen bonding interactions between uncoordinated oxygen and the O−H of the phosphonate group. Thermogravimetric and dynamic water sorption analysis demonstrated exceptional thermal robustness of BAM-5 until 230°C and notable water affinity. Proton conductivity measurements found increasing proton conductive properties with increasing temperature and relative humidity.The latter is correlated with the material’s water uptake since the structure itself does not contain any permanent lattice water molecules. A maximum proton conductivity of 6.6 × 10−6 S cm−1 was found at 80°C and 98% RH. To the best of our knowledge, no dense, nonporous 1D coordination polymer without lattice or coordinated solvent molecules has shown comparable proton con� ductivity. The high activation energy suggests a combination of both, a Grotthuss-type proton hopping through the hydrogen� bonded framework, and a vehicular process, in which protons are carried along with absorbed water molecules. Zeitschrift für anorganische und allgemeine Chemie 0044-2313 10.1002/zaac.202500187 urn:nbn:de:kobv:b43-651382 true journal-article http://creativecommons.org/licenses/by/4.0/ crossref PersonAuthorFirstName_1,PersonAuthorLastName_1,PersonAuthorIdentifierOrcid_1,PersonAuthorFirstName_2,PersonAuthorLastName_2,PersonAuthorFirstName_3,PersonAuthorLastName_3,PersonAuthorFirstName_4,PersonAuthorLastName_4,PersonAuthorIdentifierOrcid_4,PersonAuthorFirstName_5,PersonAuthorLastName_5,PersonAuthorIdentifierOrcid_5,PublisherName,TitleMain_1,Language,TitleAbstract_1,TitleParent_1,ArticleNumber,PublishedYear,IdentifierIssn,Enrichmentlocal_crossrefLicence doi-import 15.12.2025 false true Creative Commons - CC BY - Namensnennung 4.0 International Alina Schmalz Charles Gaston Eby Caitlin Moss Biswajit Bhattacharya Franziska Emmerling eng uncontrolled Coordination polymers eng uncontrolled Phosphonate ligand eng uncontrolled Proton conduction eng uncontrolled X-ray diffraction Ingenieurwissenschaften und zugeordnete Tätigkeiten 6 Materialchemie 6.3 Strukturanalytik Material Verlagsliteratur Datei für die Öffentlichkeit verfügbar ("Open Access") Wissenschaftliche Artikel der BAM 6.0 Abteilungsleitung und andere Materialdesign Bundesanstalt für Materialforschung und -prüfung (BAM) https://opus4.kobv.de/opus4-bam/files/65138/ZAAC.pdf