Controllable synthesis of 3D PdCu/Ti3C2Tx hierarchical nanostructures for chemiresistive room temperature H2 sensors

To enhance the detection performance of hydrogen (H2), we employed a self-sacrificing template method to prepare a three-dimensional (3D) PdCu-modified Ti3C2Tx nanocomposite, denoted as PdCu/Ti3C2Tx. Within 3D PdCu/Ti3C2Tx nanocomposite, PdCu as the active center component, was evenly distributed on Ti3C2Tx nanosheets. The unique architecture increased the exposure of active center sites, while the Ti3C2Tx nanosheets provided additional gas diffusion channels, thereby contributing to improved gas sensing performance. Comparing to PdCu nanoparticles, PdCu/Ti3C2Tx exhibited an enhancing response and a fast response time of 4 s to 0.5 % H2. PdCu/Ti3C2Tx also showed an ultra-low detection limit of 0.1 % H2 and excellent repeatability, selectivity and long-term stability. The outstanding gas sensing performance could be attributed to the 3D structure and the heterostructure between PdCu and Ti3C2Tx. The insights gained from this study provide novel perspectives for designing and synthesizing high-performance gas-sensitive materials. •Three-dimensional PdCu-modified Ti3C2Tx nanocomposites were prepared by self-sacrificing template method.•The PdCu/Ti3C2Tx nanocomposite has excellent sensing characteristics for hydrogen, and the response speed is only 4 s.•The outstanding sensing performance were attributed to the 3D structure and the heterostructure between PdCu and Ti3C2Tx.