Silkworms as a factory of functional wearable energy storage fabrics

Abstract

Feeding Bombyx mori larvae with chemically-modified diets affects the structure and properties of the resulted silk. Herein, we provide a road map for the use of silkworms as a factory to produce semiconducting/metallic natural silk that can be used in many technological applications such as supercapacitor electrodes. The silkworms were fed with four different types of chemicals; carbon material (graphite), sulfide (MoS 2 ), oxide (TiO 2 nanotubes), and a mixture of reactive chemicals (KMnO 4 /MnCl 2 ). All the fed materials were successfully integrated into the resulted silk. The capacitive performance of the resulted silk was evaluated as self-standing fabric electrodes as well as on glassy carbon substrates. The self-standing silk and the silk@glassy carbon substrate showed a great enhancement in the capacitive performance over that of the unmodified counterparts. The specific capacitance of the self-standing blank silk negative and positive electrodes was enhanced 4 and 5 folds at 10 mV/s, respectively upon the modification with KMnO 4 /MnCl 2 compared to that of the plain silk electrodes.

Synthesis and Processing of Nanomaterials Mediated by Living Organisms

“…[46,48,55] Another recurrent family of NMs fed to silkworms are metal and metal oxide NPs.R egarding ZMNPs,t he most investigated are Ag NPs, [56][57][58][59] but there are also reports on feeding with Cu [56,60] and Fe [60] NPs.While the mechanical improvements of the silk in these cases do not match those from carbon-based NMs (Figure 3c,d), the actual benefits lie in the conferral of new properties such as ap otent antibacterial effect [57,58] or the electricity harvesting from silk cocoons. [59] As imilar trend is observed for feeding with metal oxide NPs,which in this case are mostly based on TiO 2 [44,60,61] but there are also specific examples with F 3 O 4 , [49] MoS 2 [61] or MoO 2 [62,63] NPs.F or instance,t he excellent UV-absorbing ability of TiO 2 led to UV-resistant silks, [44] the magnetic properties of F 3 O 4 provided intrinsically magnetic silk, [49] and MoO 2 NPs led to an enhancement of specific capacitance in carbonized silk. [62,63] All the aforementioned breakthroughs are possible because NMs are actually incorporated into the silk by the action of silkworms.T his has been corroborated by some authors using specific characterization techniques.F or instance,CNTs and graphene have been detected within the silk Angewandte by Raman spectroscopy, [51,52] and metal NPs by ICP-MS and advanced electron microscopy techniques.…”

“…While the mechanical improvements of the silk in these cases do not match those from carbon‐based NMs (Figure 3 c,d), the actual benefits lie in the conferral of new properties such as a potent antibacterial effect [57, 58] or the electricity harvesting from silk cocoons [59] . A similar trend is observed for feeding with metal oxide NPs, which in this case are mostly based on TiO 2 [44, 60, 61] but there are also specific examples with F 3 O 4 , [49] MoS 2 [61] or MoO 2 [62, 63] NPs. For instance, the excellent UV‐absorbing ability of TiO 2 led to UV‐resistant silks, [44] the magnetic properties of F 3 O 4 provided intrinsically magnetic silk, [49] and MoO 2 NPs led to an enhancement of specific capacitance in carbonized silk [62, 63]…”

Synthesis and Processing of Nanomaterials Mediated by Living Organisms

“…[46,48,55] Another recurrent family of NMs fed to silkworms are metal and metal oxide NPs.R egarding ZMNPs,t he most investigated are Ag NPs, [56][57][58][59] but there are also reports on feeding with Cu [56,60] and Fe [60] NPs.While the mechanical improvements of the silk in these cases do not match those from carbon-based NMs (Figure 3c,d), the actual benefits lie in the conferral of new properties such as ap otent antibacterial effect [57,58] or the electricity harvesting from silk cocoons. [59] As imilar trend is observed for feeding with metal oxide NPs,which in this case are mostly based on TiO 2 [44,60,61] but there are also specific examples with F 3 O 4 , [49] MoS 2 [61] or MoO 2 [62,63] NPs.F or instance,t he excellent UV-absorbing ability of TiO 2 led to UV-resistant silks, [44] the magnetic properties of F 3 O 4 provided intrinsically magnetic silk, [49] and MoO 2 NPs led to an enhancement of specific capacitance in carbonized silk. [62,63] All the aforementioned breakthroughs are possible because NMs are actually incorporated into the silk by the action of silkworms.T his has been corroborated by some authors using specific characterization techniques.F or instance,CNTs and graphene have been detected within the silk by Raman spectroscopy, [51,52] and metal NPs by ICP-MS and advanced electron microscopy techniques.…”

“…While the mechanical improvements of the silk in these cases do not match those from carbon‐based NMs (Figure 3 c,d), the actual benefits lie in the conferral of new properties such as a potent antibacterial effect [57, 58] or the electricity harvesting from silk cocoons [59] . A similar trend is observed for feeding with metal oxide NPs, which in this case are mostly based on TiO 2 [44, 60, 61] but there are also specific examples with F 3 O 4 , [49] MoS 2 [61] or MoO 2 [62, 63] NPs. For instance, the excellent UV‐absorbing ability of TiO 2 led to UV‐resistant silks, [44] the magnetic properties of F 3 O 4 provided intrinsically magnetic silk, [49] and MoO 2 NPs led to an enhancement of specific capacitance in carbonized silk [62, 63] …”

Bimetallic Co–W–S Chalcogenides Confined in N,S-Codoped Porous Carbon Matrix Derived from Metal–Organic Frameworks for Highly Stable Electrochemical Supercapacitors

“…The high-resolution transmission electron microscopy (HRTEM) image (Figure 3b) revealed interplanar spacings of 0.62 and 0.29 nm, which are indexed to the WS 2 (002) plane and the Co 1−x S (100) plane, respectively. 29,30 Moreover, the ring pattern of the selected area electron diffraction (SAED) demonstrated the polycrystalline nature of the synthesized binary sulfide composite (Co−W−S@N,S-PC), Figure 3c. The SAED pattern revealed four clear lattice planes indexed to the (002) plane of WS 2 , (100) of Co 1−x S, and the two lattice (002) and (101) planes of the derived graphitic carbon matrix, in accordance with the XRD outcomes.…”