0.05 g graphene oxide mixed with 16 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 0.2 mL hydrazine hydrate added for reduction to form graphene-fibroin nanofiber composite. 2.15 g FeCl3·6H₂O added and stirred to dissolution. Mixture reacted in reactor at 160°C for 20 h. Product cooled, centrifuged, washed, dried in vacuum. Solid powder calcinated in argon atmosphere at 400°C for 5 h, then cooled to room temperature to yield graphene/porous iron oxide nanorod composite. SEM/TEM show 1D rod-shaped structure with honeycomb holes; XRD confirms iron oxide; Raman confirms graphene/iron oxide composite.

0.05 g graphene oxide mixed with 0.19 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 1 mL hydrazine hydrate added for reduction. 1 g FeCl3·6H₂O added and stirred. Reacted at 120°C for 36 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 320°C for 8 h, cooled to room temperature. SEM shows parts rod-shaped, parts irregular.

0.05 g graphene oxide mixed with 10 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 20 µL hydrazine hydrate added for reduction. 3 g FeCl3·6H₂O added and stirred. Reacted at 200°C for 8 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 450°C for 3 h, cooled to room temperature. SEM shows rod-shaped composite.

Same as Embodiment 1 except step (5) calcination was omitted. SEM shows rod-shaped structure before calcination. XRD shows pre-calcination product is FeOOH.

0.05 g graphene oxide mixed with 16 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 0.2 mL hydrazine hydrate added for reduction to form graphene-fibroin nanofiber composite. 2.15 g FeCl3·6H₂O added and stirred to dissolution. Mixture reacted in reactor at 160°C for 20 h. Product cooled, centrifuged, washed, dried in vacuum. Solid powder calcinated in argon atmosphere at 400°C for 5 h, then cooled to room temperature to yield graphene/porous iron oxide nanorod composite. SEM/TEM show 1D rod-shaped structure with honeycomb holes; XRD confirms iron oxide; Raman confirms graphene/iron oxide composite.

0.05 g graphene oxide mixed with 0.19 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 1 mL hydrazine hydrate added for reduction. 1 g FeCl3·6H₂O added and stirred. Reacted at 120°C for 36 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 320°C for 8 h, cooled to room temperature. SEM shows parts rod-shaped, parts irregular.

0.05 g graphene oxide mixed with 10 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 20 µL hydrazine hydrate added for reduction. 3 g FeCl3·6H₂O added and stirred. Reacted at 200°C for 8 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 450°C for 3 h, cooled to room temperature. SEM shows rod-shaped composite.

Same as Embodiment 1 except step (5) calcination was omitted. SEM shows rod-shaped structure before calcination. XRD shows pre-calcination product is FeOOH.

0.05 g graphene oxide mixed with 16 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 0.2 mL hydrazine hydrate added for reduction to form graphene-fibroin nanofiber composite. 2.15 g FeCl3·6H₂O added and stirred to dissolution. Mixture reacted in reactor at 160°C for 20 h. Product cooled, centrifuged, washed, dried in vacuum. Solid powder calcinated in argon atmosphere at 400°C for 5 h, then cooled to room temperature to yield graphene/porous iron oxide nanorod composite. SEM/TEM show 1D rod-shaped structure with honeycomb holes; XRD confirms iron oxide; Raman confirms graphene/iron oxide composite.

0.05 g graphene oxide mixed with 0.19 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 1 mL hydrazine hydrate added for reduction. 1 g FeCl3·6H₂O added and stirred. Reacted at 120°C for 36 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 320°C for 8 h, cooled to room temperature. SEM shows parts rod-shaped, parts irregular.

0.05 g graphene oxide mixed with 10 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 20 µL hydrazine hydrate added for reduction. 3 g FeCl3·6H₂O added and stirred. Reacted at 200°C for 8 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 450°C for 3 h, cooled to room temperature. SEM shows rod-shaped composite.

Same as Embodiment 1 except step (5) calcination was omitted. SEM shows rod-shaped structure before calcination. XRD shows pre-calcination product is FeOOH.

0.05 g graphene oxide mixed with 16 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 0.2 mL hydrazine hydrate added for reduction to form graphene-fibroin nanofiber composite. 2.15 g FeCl3·6H₂O added and stirred to dissolution. Mixture reacted in reactor at 160°C for 20 h. Product cooled, centrifuged, washed, dried in vacuum. Solid powder calcinated in argon atmosphere at 400°C for 5 h, then cooled to room temperature to yield graphene/porous iron oxide nanorod composite. SEM/TEM show 1D rod-shaped structure with honeycomb holes; XRD confirms iron oxide; Raman confirms graphene/iron oxide composite.

0.05 g graphene oxide mixed with 0.19 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 1 mL hydrazine hydrate added for reduction. 1 g FeCl3·6H₂O added and stirred. Reacted at 120°C for 36 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 320°C for 8 h, cooled to room temperature. SEM shows parts rod-shaped, parts irregular.

0.05 g graphene oxide mixed with 10 mL of 5.06 wt% fibroin solution, pH adjusted to 10, 20 µL hydrazine hydrate added for reduction. 3 g FeCl3·6H₂O added and stirred. Reacted at 200°C for 8 h. Product cooled, centrifuged, washed, dried in vacuum. Calcinated in argon at 450°C for 3 h, cooled to room temperature. SEM shows rod-shaped composite.

Same as Embodiment 1 except step (5) calcination was omitted. SEM shows rod-shaped structure before calcination. XRD shows pre-calcination product is FeOOH.