Photomechanical actuation is the conversion of light energy into mechanical energy through some smart materials. Infrared-responsive smart materials have become an emerging field of research due to easy availability and eco-friendly nature of their stimulus in the form of sunlight, which contains about 50% of near-infrared(nIR) making these materials useful at macro-scale photoactuator applications. Here, we demonstrate fabrication of highly versatile nIR triggered photoactuators based on graphene oxide/polycarbonate bilayers that offers fast, low-cost fabrication, large deflection, reversible actuation and wavelength-selective response. The photoactuators are realized by vacuum filtration of graphene oxide/water dispersion through polycarbonate membrane resulting graphene oxide/polymer bilayer structure. The photoactuation response was measured in the form of deflection from equilibrium position as a result of infrared-irradiation. The deflection is caused by the generated thermal stress at the interface of bilayers due to mismatch of thermal expansion coefficient as a results of nIR absorption by graphene oxide and subsequent temperature rise. A maximum deflection of 12 mm (circular-shaped structure with diameter 28 mm) with corresponding bending curvature of 0.33 cm−1 was shown by this photoactuator for illumination intensity of 106 mW/cm2. Few applications of these photoactuators such as sunlight-driven smart curtain, infrared actuated curtain and self-folding box are also demonstrated
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机译：光机械致动是通过某些智能材料将光能转换为机械能。红外响应智能材料由于其易获得性和以阳光形式的刺激而具有生态友好性，已成为新兴的研究领域，其中包含约50％的近红外（nIR），使这些材料在宏观上非常有用光致动器的应用。在这里，我们演示了基于氧化石墨烯/聚碳酸酯双层的多功能nIR触发光致动器的制造，该光致动器可提供快速，低成本的制造，大挠度，可逆驱动和波长选择性响应。光致动器是通过将氧化石墨烯/水分散体通过聚碳酸酯膜真空过滤得到的氧化石墨烯/聚合物双层结构而实现的。作为红外辐射的结果，以偏离平衡位置的形式测量了光致响应。挠曲是由于热膨胀系数不匹配而在双层界面上产生的热应力引起的，该热应力是氧化石墨烯对nIR的吸收和随后温度升高的结果。通过这种光致动器，在最大照明强度为106 mW / cm 2 <的情况下，最大挠度为12 mm（直径为28 mm的圆形结构），相应的弯曲曲率为0.33 cm -1 。 / sup>。还展示了这些光致动器的很少应用，例如阳光驱动的智能窗帘，红外致动的窗帘和自动折叠盒。
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