Microwave has been traditionally used as fast and uniform heating source in chemical reactions, where polar solvent is often required to generate heat under microwave irradiation. In this work, solid acid catalysts were synthesized with engineered surface polarity and microwave absorption. Therefore, heat generation and reaction can be coupled at catalyst surface to improve the overall energy efficiency of reactions. Specifically, titanate nanostructures (nanocube, nanotube and nanobelt) were synthesized by using different alkalis in hydrothermal reactions. The titanate intermediates (protonated titanates, H₂Ti_nO_2n+1, n = 3, 5) have been demonstrated critical in controlling the catalyst pore structure, surface area, crystal composition and the quantity of acid sites. Especially, the open crystal structure of H₂Ti₃O₇ allowed interlayer polarization of titanates, which was critical to enable a large number of Ti-O-SO₄²⁻ acid sites. The Ti-O-SO₄²⁻ not only serves as catalytic active site, but also offers heat generation capability under microwave irradiation. Among the titanate nanostructures, titanate nanotube shows the best heat generation capability and gives the largest rate constant of 0.31 min⁻¹. The reaction equilibrium of fructose to HMF conversion can be reached within a few minutes at 140 °C. Benefited from the surface acidity and microwave heating ability, the energy efficiency of the reaction by titanate nanotube (5.6 mmol (KJ L)⁻¹) is 9 times higher than commercial TiO₂ solid acid (0.6 mmol (KJ L)⁻¹). The interlayer polarization is revealed as the major reason for the enhanced microwave response of titanate catalyst and energy efficiency of the reactions.

传统上，微波已被用作化学反应中的快速，均匀的加热源，在化学反应中，通常需要极性溶剂在微波辐射下产生热量。在这项工作中，合成了具有设计的表面极性和微波吸收能力的固体酸催化剂。因此，生热和反应可以在催化剂表面耦合以提高反应的整体能量效率。具体而言，通过在水热反应中使用不同的碱合成了钛酸酯纳米结构（纳米立方，纳米管和纳米带）。钛酸酯中间体（质子化钛酸酯，H ₂ Ti _n O _{2n + 1}，n = 3，5）已被证明对控制催化剂的孔结构，表面积，晶体组成和酸位的数量至关重要。特别是，H ₂ Ti ₃ O ₇的开放晶体结构允许钛酸酯的层间极化，这对于实现大量Ti-O-SO ₄ ^2-酸位至关重要。Ti-O-SO ₄ ^2-不仅具有催化活性，还具有微波辐射下的生热能力。在钛酸酯纳米结构中，钛酸酯纳米管显示出最佳的生热能力，并提供最大的速率常数0.31 min ^-1。果糖向HMF转化的反应平衡可在140°C的几分钟内达到。受益于表面酸度和微波加热能力，钛酸酯纳米管（5.6 mmol（KJ L）^-1）进行反应的能量效率是市售TiO ₂固体酸（0.6 mmol（KJ L）^-1）的9倍。揭示了层间极化是钛酸酯催化剂的微波响应增强和反应的能量效率提高的主要原因。