The synchronous harvesting and conversion of multiple renewable energy sources for chemical fuel production and environmental remediation in a single system is a holy grail in sustainable energy technologies. However, it is challenging to develop advanced energy harvesters that satisfy different working mechanisms. Here, we theoretically and experimentally disclose the use of MXene materials as versatile catalysts for multi-energy utilization. Ti3C2TX MXene shows remarkable catalytic performance for organic pollutant decomposition and H2 production. It outperforms most reported catalysts under the stimulation of light, thermal, and mechanical energy. Moreover, the synergistic effects of piezo-thermal and piezo-photothermal catalysis further improve the performance when using Ti3C2TX. A mechanistic study reveals that hydroxyl and superoxide radicals are produced on the Ti3C2TX under diverse energy stimulation. Furthermore, similar multi-functionality is realized in Ti2CTX, V2CTX, and Nb2CTX MXene materials. This work is anticipated to open a new avenue for multisource renewable energy harvesting using MXene materials.
Spatial separation of electrons and holes is critical for improving their photocatalytic performance, which is ascribed to the suppressed photoinduced carriers' recombination among facets. In this work, the ZnO-Au-MnO x heterogeneous nanostructure photocatalyst was prepared by photodepositing Au and MnO x on the ZnO polar {0001} and {101̅0} crystal facets, respectively. The photocatalytic performance of ZnO-Au-MnO x was higher than ZnO and ZnO-Au for the degradation of rhodamine B dye under UV light irradiation. Due to the potential difference between different crystal planes of zinc oxide, electrons and holes will migrate to different crystal planes of zinc oxide. This will lead to the deposition of Au and MnO x on different crystal facets of zinc oxide. The efficient photoinduced carrier separation of ZnO-Au-MnO x resulted in the high photocatalytic activity, which is well supported by photoelectrochemical and photoluminescence analyses. The intermediated species formed during the reaction were investigated by high performance liquid chromatography. The reaction mechanism was investigated by radical trapping experiments and electron spin resonance analysis. The special structure of selective deposition of redox cocatalysts on the different facets should be promising and intriguing for designing highly efficient photocatalysts.