The need for sustainable technologies to address environmental pollution and energy crisis is paramount. Here we present a novel multifunctional nanocomposite, free standing films by combining piezoelectric molybdenum sulphide (MoS₂) nanoflower with poly vinylidene fluoride (PVDF) polymer, which can harness otherwise wasted mechanical energy for useful energy generation or water purification. The unique MoS₂ nanoflower morphology is exploited to render the whole nanocomposite piezo active. A number of features are demonstrated to establish potential practical usage. Firstly, the nanocomposite is piezoelectric and piezocatalytic simultaneously without requiring any poling step (i.e. self-poled). Secondly, the self-poled piezoelectricity is exploited to make a nanogenerator to produce electrical power. The nanogenerator produced >80 V under human finger tapping with a remarkable power density, reaching 47.14 mW cm⁻³. The nanocomposite film is made by simple solution casting, and the corresponding nanogenerator powers up 25 commercial LEDs by finger tapping. Last but not the least, the developed films show efficient, fast and stable piezocatalytic dye degradation efficiency (>90% within 20 min) against four different toxic and carcinogenic dyes under dark condition using only ultrasonic vibration. Reusability of at least 10 times is also demonstrated without any loss of catalytic activity. Overall, our nanocomposite has clear potential for use as self-powered sensor and energy harvester, and in water remediation systems. It should potentially also be deployable as a surface mounted film/coating in process engineering, industrial effluent management and healthcare devices systems.

对解决环境污染和能源危机的可持续技术的需求至关重要。在这里，我们通过将压电硫化钼 (MoS ₂ ) 纳米花与聚偏二氟乙烯 (PVDF) 聚合物相结合，提出了一种新型多功能纳米复合材料、独立式薄膜，该聚合物可以利用原本浪费的机械能来产生有用的能源或净化水。独特的 MoS ₂纳米花形态被用来使整个纳米复合压电材料具有活性。演示了许多功能以建立潜在的实际用途。首先，纳米复合材料同时具有压电和压电催化作用，不需要任何极化步骤（即自极化）。其次，利用自极化压电性来制造纳米发电机以产生电力。纳米发电机在人类手指敲击下产生 >80 V 的功率密度，达到 47.14 mW cm ^-3. 纳米复合薄膜是通过简单的溶液浇铸制成的，相应的纳米发电机通过手指敲击为 25 个商用 LED 供电。最后但并非最不重要的是，开发的薄膜在黑暗条件下仅使用超声波振动对四种不同的有毒和致癌染料显示出高效、快速和稳定的压电催化染料降解效率（20 分钟内>90%）。还证明了至少 10 次的可重复使用性而没有任何催化活性损失。总体而言，我们的纳米复合材料具有用作自供电传感器和能量收集器以及水修复系统的明显潜力。它也有可能在工艺工程、工业废水管理和医疗保健设备系统中作为表面贴装薄膜/涂层进行部署。