Small
·
2024
·Vol. 20
·期 26
·2310387
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IF 13
Wei Luo,Yanli Yu,Yucheng Wu,Wenbin Wang,Yimin Jiang,Wei Shen,Rongxing He,Wei Su,Ming Li
Rational design of heterostructure catalysts through phase engineering strategy plays a critical role in heightening the electrocatalytic performance of catalysts. Herein, a novel amorphous/crystalline (a/c) heterostructure (a-CoS/Ni 3 S 2 ) is manufactured by a facile hydrothermal sulfurization method. Strikingly, the interface coupling between amorphous phase (a-CoS) and crystalline phase (Ni 3 S 2 ) in a-CoS/Ni 3 S 2 is much stronger than that between crystalline phase (c-CoS) and crystalline phase (Ni 3 S 2 ) in crystalline/crystalline (c/c) heterostructure (c-CoS/Ni 3 S 2 ) as control sample, which makes the meta-stable amorphous structure more stable. Meanwhile, a-CoS/Ni 3 S 2 has more S vacancies (S v ) than c-CoS/Ni 3 S 2 because of the presence of an amorphous phase. Eventually, for the oxygen evolution reaction (OER), the a-CoS/Ni 3 S 2 exhibits a significantly lower overpotential of 192 mV at 10 mA cm −2 compared to the c-CoS/Ni 3 S 2 (242 mV). An exceptionally low cell voltage of 1.51 V is required to achieve a current density of 50 mA cm −2 for overall water splitting in the assembled cell (a-CoS/Ni 3 S 2 || Pt/C). Theoretical calculations reveal that more charges transfer from a-CoS to Ni 3 S 2 in a-CoS/Ni 3 S 2 than in c-CoS/Ni 3 S 2 , which promotes the enhancement of OER activity. This work will bring into play a fabrication strategy of a/c catalysts and the understanding of the catalytic mechanism of a/c heterostructures.
研究领域:
材料科学
·
电化学
·
催化化学
·
纳米材料
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能源材料
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 10
·1804546
·
IF 10.856
Jing Yang,Donghua Guo,Shulin Zhao,Yue Lin,Rui Yang,Dongdong Xu,Naien Shi,Xiaoshu Zhang,Lingzhi Lu,Ya-Qian Lan,Jianchun Bao,Min Han
As one class of important functional materials, transition metal phosphides (TMPs) nanostructures show promising applications in catalysis and energy storage fields. Although great progress has been achieved, phase-controlled synthesis of cobalt phosphides nanocrystals or related nanohybrids remains a challenge, and their use in overall water splitting (OWS) is not systematically studied. Herein, three kinds of cobalt phosphides nanocrystals encapsulated by P-doped carbon (PC) and married with P-doped graphene (PG) nanohybrids, including CoP@PC/PG, CoP-Co 2 P@PC/PG, and Co 2 P@PC/PG, are obtained through controllable thermal conversion of presynthesized supramolecular gels that contain cobalt salt, phytic acid, and graphene oxides at proper temperature under Ar/H 2 atmosphere. Among them, the mixed-phase CoP-Co 2 P@PC/PG nanohybrids manifest high electrocatalytic activity toward both hydrogen and oxygen evolution in alkaline media. Remarkably, using them as bifunctional catalysts, the fabricated CoP-Co 2 P@PC/PG || CoP-Co 2 P@PC/PG electrolyzer only needs a cell voltage of 1.567 V for driving OWS to reach the current density at 10 mA cm −2 , superior to their pure-phase counterparts and recently reported bifunctional catalysts based devices. Also, such a CoP-Co 2 P@PC/PG || CoP-Co 2 P@PC/PG device exhibits outstanding stability for OWS. This work may shed some light on optimizing TMPs nanostructures based on phase engineering, and promote their applications in OWS or other renewable energy options.
研究领域:
材料科学
·
电催化
·
能源化学
·
纳米材料
·
可再生能源
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Xin Fang,Jun Chen,Jing Zhan
Semiconductor-based heterostructure photocatalyst attracts extensive attention because of its excellent interface charge transfer/separation ability. Here, the β-Bi 2 O 3 /CeO 2 heterostructure photocatalysts are fabricated via a simple mechanochemical couple with thermal decomposition strategy. The introduction of CeO 2 can not only stabilize the phase of β-Bi 2 O 3 but also construct a heterojunction at the interface, resulting in the improved visible light response capability and efficient transfer and separation of photo-generated charges. Besides, the increased specific surface area and pore volume increase the active sites to accelerate the adsorption and mass transfer process. As a result, the β-Bi 2 O 3 /CeO 2 heterostructure photocatalyst shows remarkably enhanced photocatalytic performance towards malachite green (MG) degradation under visible-light irradiation compared with the Bi 2 O 3 and CeO 2 . The degradation efficiency of MG over the optimized β-Bi 2 O 3 /CeO 2 heterostructure reaches up to 97.5% after 2 h of visible-light irradiation. This work provides a new approach for the rational design of heterojunction photocatalyst combined with phase and interface engineering and opens up a potential avenue for efficient application of Bi 2 O 3 photocatalyst for efficient energy conversion.
研究领域:
材料科学
·
环境化学
·
光催化
·
纳米材料
·
能源转换
✓ 已验证
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-10
·
IF 14.7
Zhou Jun,Zhang Guitao,Wang Wenhui,Chen Qian,Zhao Weiwei,Liu Hongwei,Zhao Bei,Ni Zhenhua,Lu Junpeng
Multiple structural phases of tellurium (Te) have opened up various opportunities for the development of two-dimensional (2D) electronics and optoelectronics. However, the phase-engineered synthesis of 2D Te at the atomic level remains a substantial challenge. Herein, we design an atomic cluster density and interface-guided multiple control strategy for phase- and thickness-controlled synthesis of α -Te nanosheets and β -Te nanoribbons (from monolayer to tens of μm) on WS 2 substrates. As the thickness decreases, the α -Te nanosheets exhibit a transition from metallic to n-type semiconducting properties. On the other hand, the β -Te nanoribbons remain p-type semiconductors with an ON-state current density (I ON ) up to ~ 1527 μA μm −1 and a mobility as high as ~ 690.7 cm 2 V −1 s −1 at room temperature. Both Te phases exhibit good air stability after several months. Furthermore, short-channel (down to 46 nm) β -Te nanoribbon transistors exhibit remarkable electrical properties (I ON = ~ 1270 μA μm −1 and ON-state resistance down to 0.63 kΩ μm) at V ds = 1 V.
研究领域:
材料科学
·
纳米技术
·
电子学
·
光电子学
✓ 已验证
DOI
高影响因子